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Lower Boise River TMDL Five-Year Review

Final

Department of Environmental Quality February 2009

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Lower Boise River TMDL Five-Year Review

February 2009

Prepared by: Susan Beattie Boise Regional Office Department of Environmental Quality 1455 N. Orchard St. Boise, ID 83706

February 2009

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table of Contents Abbreviations, Acronyms, and Symbols................................................................................. ix About Assessment Units ................................................................................................ xv TMDL Targets and Load Allocations............................................................................xviii Key Findings ................................................................................................................. xxi Summary of Recommendations...................................................................................xxxi Section 1: Introduction ...........................................................................................................1 About Assessment Units ..................................................................................................1 Subbasin at a Glance.......................................................................................................2 Section 2: TMDL Overview ....................................................................................................7 Listed Waters ...................................................................................................................7 Permitted Point Sources ..................................................................................................8 Nonpoint Sources ............................................................................................................9 Pollutant Targets ............................................................................................................10 Water Quality Criteria ................................................................................................10 Control/Monitoring Points ..........................................................................................11 Load Capacity ...........................................................................................................11 Load Allocations ........................................................................................................12 Margin of Safety ........................................................................................................15 Seasonal Variation ....................................................................................................15 Reserve for Growth ...................................................................................................16 Tributary Subbasin Assessments ..................................................................................16 Section 3: Beneficial Use Status ..........................................................................................19 Changes to Subbasin Characteristics ............................................................................27 Pollution Source Review ................................................................................................27 Point Sources ............................................................................................................27 Nonpoint Sources......................................................................................................30 Summary of Analysis of Current Water Quality Data .....................................................31 Sediment ...................................................................................................................31 Bacteria .....................................................................................................................39 Temperature..............................................................................................................45 Dissolved Oxygen .....................................................................................................54 pH..............................................................................................................................56 Flow and Habitat .......................................................................................................61 Summary of Beneficial Uses ..........................................................................................63 Status of Beneficial Uses ..........................................................................................65 Summary of Recommendations.....................................................................................73 Section 4. Review of Implementation Plan and Activities .....................................................91 Implementation Plan ......................................................................................................91 Responsible Parties .......................................................................................................91 Planned Activities...........................................................................................................92 Accomplished Activities .................................................................................................96 Point Sources ............................................................................................................97 Nonpoint Sources......................................................................................................98 Monitoring ......................................................................................................................99 Sediment Monitoring .................................................................................................99

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Bacteria Monitoring .................................................................................................101 Future Strategy ............................................................................................................102 Time Frame..................................................................................................................103 Section 5. Summary of Five Year Review...........................................................................105 Review Process ...........................................................................................................105 Changes in Subbasin...................................................................................................105 TMDL Analysis.............................................................................................................106 Bacteria ...................................................................................................................106 Sediment .................................................................................................................106 Temperature............................................................................................................107 Review of Beneficial Uses ...........................................................................................108 Water Quality Criteria...................................................................................................108 Future TMDLs ..............................................................................................................108 Watershed Advisory Group Consultation .....................................................................109 References Cited ................................................................................................................112 Glossary ..............................................................................................................................117 Appendix A. Unit Conversion Chart ....................................................................................131 Appendix B. State and Site-Specific Standards and Criteria ..............................................133 Appendix C. Data Tables and Graphs ................................................................................143 Appendix D. Designated Management Agency Reports of Implementation Activities and Effectiveness.......................................................................................................................291 Appendix E. Assessment Unit Maps ...................................................................................305

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List of Tables Table A. 1999 TMDLs and correlating assessment units from 2002 Water Quality Standards revisions and associated load allocations, implementation activities and monitoring data................................................................................................... xix Table B. Summary of assessment units, draft 2008 Integrated Report, existing TMDLs, and five-year review results.......................................................................................xxii Table 1. Summary of §303(d)-listed stream segments in the Lower Boise River TMDL Subbasin Assessment, Total Maximum Daily Loads (DEQ, 1999). ......................7 Table 2. Load Allocations, Lower Boise River 1999 TMDL.....................................................8 Table 3. Municipal wastewater treatment plants (WWTP) and selected permitted point sources discharging to the Lower Boise River and its tributaries in 1998 (DEQ, 1999). ....................................................................................................................8 Table 4. Subbasin point source wasteload allocations for total suspended sediment (TSS) (DEQ, 1999; 2008). .............................................................................................12 Table 5. Subbasin TMDL (DEQ, 1999) tributary and nonpoint source load allocations for total suspended sediment (TSS). ........................................................................13 Table 6. Lower Boise River TMDL (DEQ, 1999) and Addendum (DEQ, 2008) bacteria load allocations for mainstem and point source locations. ..........................................13 Table 7. Lower Boise River TMDL (DEQ, 1999) and Addendum (DEQ, 2008) bacteria load allocations for nonpoint source locations (tributaries and drains)........................14 Table 8. Summary of Lower Boise River and tributaries subbasin nutrient and sediment assessment (2001). .............................................................................................16 Table 9. Lower Boise River subbasin 2002 303(d) list.........................................................17 Table 10. Summary of Lower Boise River subbasin impairments from the draft 2008 Integrated Report and beneficial uses from Idaho water quality standards (2007). ............................................................................................................................20 Table 11. Idaho Water Quality Standards, adopted in 2007 (not yet approved by EPA), applicable to the Lower Boise River subbasin.....................................................23 Table 12. Summary of Lower Boise River subbasin data sources used in five-year review, determination of beneficial use attainment and pollutant type.............................24 Table 13. NPDES-permitted point sources in the Lower Boise River subbasin, as of March 2008. ...................................................................................................................28 Table 14. Load analysis of suspended sediment (SSC or TSS) data collected at some Lower Boise River subbasin TMDL Load Allocation (LA) locations in 2008...................34 Table 15. Load analysis of suspended sediment, data collected at Lower Boise River subbasin TMDL WLA locations in 2008...............................................................38 Table 16. Summary of benthic macroinvertebrate (5-riffle composite) data collected by the USGS from mainstem Lower Boise River, 2003-2006. Temperature tolerance indices compiled by DEQ. ...................................................................................51 Table 17. Summary of temperature tolerance statistics of benthic macroinvertebrate organisms collected by DEQ through the Beneficial Use Reconnaissance Program (BURP), 2003. ......................................................................................53 Table 18. Summary of temperature tolerance of fish community data collected by the USGS and DEQ between 2003 and 2004. .....................................................................54

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Table 19. Summary of assessment units, draft 2008 Integrated Report, existing TMDLs, and five-year review results........................................................................................65 Table 20. Roles and responsibilities for reporting on TMDL progress in the Lower Boise River subbasin (as presented in Table 16 of the 2003 implementation plan)......94 Table 21. Implementation activities in progress and planned for the Lower Boise River subbasin as of May 2008. ...................................................................................98 Table 22. TMDL locations for tributary, nonpoint, and point source load allocations (LA) and wasteload allocations (WLA) for sediment and reported sediment data compared to TMDL targets.................................................................................................100 Table 23. Bacteria data at TMDL control locations for tributary and nonpoint sources compared to TMDL Addendum (2007) targets (126 geomean cfu/100mL).......101 Table 24. Summary of recommendations and comments from the Lower Boise Watershed Advisory Group..................................................................................................109 Table C-1. USGS data from Lower Boise River subbasin locations between 2003 and 2008. ..........................................................................................................................144 Table C-2. Data provided by the Idaho State Department of Agriculture from locations in the Lower Boise River subbasin between 1998 and 2007. .....................................153 Table C-3. Data collected by City of Nampa near Indian Creek Wastewater Treatment Plant between 2003 and 2008. ...................................................................................163 Table C- 4. Reported results of data collected by the Bureau of Reclamation from locations in the Lower Boise River subbasin between 1999 and 2008.............................172 Table C-5. Data collected by DEQ from locations in the Lower Boise River subbasin in 2008. ..........................................................................................................................177 Table C-6. Aquatic life data collected by DEQ from Lower Boise River subbasin locations between 2003 and 2008. ...................................................................................179 Table C-7. Fish community data collected by the USGS from Lower Boise River subbasin locations between 2003 and 2008.....................................................................182 Table C-8. Sediment load analysis of TMDL control locations for February and May 2008. ..........................................................................................................................182 Table C-9. Daily maximum and average water temperature, in degrees Celsius, recorded by the City of Boise between 2003 and 2008.........................................................183 Table C-10. Geomean Bacteria Data from Lower Boise River, 2003-2008, provided by the City of Boise. .....................................................................................................239 Table C-11. Water discharge and temperature data collection locations and data file quality assurance annotation for Lower Boise River Mainstem Tributary Temperature Analysis Data Summary and Technical Report, June 2005. Provided by the City of Boise, January 2009......................................................................................243 Table C-12. Daily average discharge (Q) data used to create Lower Boise River Mainstem Tributary Temperature Analysis Data Summary and Technical Report, June 2005. Data reported in cubic feet per second (cfs), provided by the City of Boise, January 2009.....................................................................................................244 Table C-13. Water temperature data (abridged) in degrees Celsius used to create Lower Boise River Mainstem Tributary Temperature Analysis Data Summary and Technical Report, June 2005. Data provided by the City of Boise, January 2009. ..........................................................................................................................263

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Table D-1. Reports of nonpoint source implementation projects in the Lower Boise River subbasin. Received from Idaho Soil Conservation Commission (ISCC) May 29, 2008. .................................................................................................................292 Table D-2. Summary of nonpoint source implementation projects, 2005 through 2008, in the Lower Boise River subbasin, by Tier. Received from Idaho Soil Conservation Commission (ISCC) January 9, 2009. ...............................................................297

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List of Figures Figure A. Streams and assessment units in Lower Boise River HUC 17050114.................xvii Figure 1. Lower Boise River subbasin and beneficial use support status of waterbodies in the subbasin from the 2008 draft Integrated Report..............................................3 Figure 2. Land use and 303(d)-listed streams in the Lower Boise River subbasin. ................4 Figure 3. Lower Boise River dams and diversions (canals) permitted through the Idaho Department of Water Resources (IDWR). .............................................................5 Figure 4. Permitted point sources with wasteload allocations in the Lower Boise River Subbasin TMDL (DEQ, 1999)................................................................................9 Figure 5. Determination Steps and Criteria for Determining Support Status of Beneficial Uses in Wadeable Streams: Water Body Assessment Guidance, Second Edition (Grafe et al., 2002). .............................................................................................22 Figure 6. Permitted point sources (wastewater treatment plants and confined animal feeding operations) in Lower Boise River subbasin as reported on the EPA Web site of NPDES permits in May 2008...............................................................................30 Figure 7. Graph of suspended sediment concentration (SSC) from USGS gage locations on the Boise River, 2003-2008. ................................................................................32 Figure 8. Graph of suspended sediment concentration (SSC) from tributary locations near the confluence with the Boise River, 2005. .........................................................33 Figure 9. Graph of suspended sediment concentration (SSC) from drains near the confluence with the Boise River, 2005. ...............................................................33 Figure 10. Satellite images of sediment plumes from drains and tributaries in the Lower Boise River subbasin. Images collected from Google Earth, March 2008. ........37 Figure 11. Sediment Load Duration Diagram from Lower Boise River TMDL Control Monitoring Location, Boise River near Middleton, 2003-2008.............................38 Figure 12. Graph of total suspended solids (TSS) concentration data from Indian Creek (AU 002_04) near the wastewater treatment plant (WWTP) in Nampa, 20032007. ...................................................................................................................39 Figure 13. Geomean Bacteria Data Collected by the City of Boise from AU 011a, Lower Boise River, 2003 and 2004. ...............................................................................40 Figure 14. Geomean Bacteria Data Collected by the City of Boise from AU 005, Lower Boise River, 2003 through 2005. ...................................................................................41 Figure 15. Geomean Bacteria Data Collected by the City of Boise from AU 001, Lower Boise River, 2005. .........................................................................................................41 Figure 16. Graph of bacteria data collected from Lower Boise River locations, 2003 to 2008. ............................................................................................................................42 Figure 17. Graph of bacteria data collected from selected Lower Boise River tributaries, 2005. ...................................................................................................................43 Figure 18. Graph of bacteria data collected from three Lower Boise River drains, 2005......43 Figure C-1. Reported results of ammonia from samples collected from the Lower Boise River Drains and Tributaries by DEQ, 2008. .....................................................286 Figure C-2. Reported results of dissolved oxygen (DO) from data collected from Lower Boise River load allocation locations by DEQ, 2008. ..................................................287

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Figure C-3. Reported results of dissolved oxygen (DO) from data collected from Sand Hollow Creek (AU 017) by DEQ, 2008. .............................................................287 Figure C-4. Reported results of water temperature from data collected from Lower Boise River load allocation locations by DEQ, 2008. ..................................................288 Figure C-5. Reported results of water temperature from data collected from Sand Hollow Creek (AU 017) by DEQ, 2008. .........................................................................288 Figure C-6. Reported results of E. coli from data collected from Lower Boise River load allocation locations by DEQ, 2008. ...................................................................289 Figure C-7. Reported results of suspended sediment from data collected from Lower Boise River load allocation locations by DEQ, 2008. ..................................................289 Figure E-1. Lower Boise River Assessment Unit 001(Lower Boise River from Indian Creek to the mouth), with surface water bodies and potential surface water pollutant sources..............................................................................................................306 Figure E-2. Lower Boise River Assessment Unit 002 and 003 (Indian Creek), with surface water bodies and potential surface water pollutant sources..............................307 Figure E-3. Lower Boise River Assessment Unit 005 (Boise River from Glenwood Bridge to Indian Creek and Mill Slough), with surface water bodies and potential surface water pollutant sources. ....................................................................................308 Figure E-4. Lower Boise River Assessment Unit 006 (Mason Creek), with surface water bodies and potential surface water pollutant sources........................................309 Figure E-6. Lower Boise River Assessment Unit 008 (Tenmile Creek), with surface water bodies and potential surface water pollutant sources........................................311 Figure E-7. Lower Boise River Assessment Unit 009 (Blacks Creek), with surface water bodies and potential surface water pollutant sources........................................312 Figure E-9. Lower Boise River Assessment Unit 011 (Boise River from Lucky Peak outfall to Glenwood Bridge), with surface water bodies and potential surface water pollutant sources. ..............................................................................................314 Figure E-10. Lower Boise River Assessment Unit 012 (Cottonwood Creek, and various springs) with surface water bodies and potential surface water pollutant sources. ..........................................................................................................................315 Figure E-11. Lower Boise Assessment Unit 013 (Dry Creek), with surface water bodies and potential surface water pollutant sources. .........................................................316 Figure E-12. Lower Boise Assessment Unit 014 (Big and Little Gulch complex), with surface water bodies and potential surface water pollutant sources..............................317 Figure E-13. Lower Boise Assessment Unit 015 (Willow Creek), with surface water bodies and potential surface water pollutant sources. ..................................................318 Figure E-14. Lower Boise Assessment Unit 016 (Langley/Graveyard Gulch complex), with surface water bodies and potential surface water pollutant sources. ................319 Figure E-15. Lower Boise Assessment Unit 017 (Sand Hollow Creek), with surface water bodies and potential surface water pollutant sources........................................320

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List of Appendices Appendix A. Unit Conversion Chart ....................................................................................131 Appendix B. State and Site-Specific Standards and Criteria ..............................................133 Appendix C. Data Tables and Graphs ................................................................................143 Appendix D. Designated Management Agency Reports of Implementation Activities and Effectiveness.......................................................................................................................291 Appendix E. Assessment Unit Maps ...................................................................................305

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Abbreviations, Acronyms, and Symbols §303(d)

Refers to section 303 subsection (d) of the Clean Water Act, or a list of impaired water bodies required by this section

μ

micro, one-one thousandth

§

Section (usually a section of federal or state rules or statutes)

ADB

assessment database

AU

assessment unit

AWS

agricultural water supply

BAG

Basin Advisory Group

BLM

United States Bureau of Land Management

BMP

best management practice

BOD

biochemical oxygen demand

BOR

United States Bureau of Reclamation

Btu

British thermal unit

BURP

Beneficial Use Reconnaissance Program

C

Celsius

CFR

Code of Federal Regulations (refers to citations in federal administrative rules)

cfs

cubic feet per second

cm

centimeters

COLD

Cold Water Communities

CWA

Clean Water Act

CWAL

cold water aquatic life

CWE

cumulative watershed effects

DEQ

Department of Environmental Quality ix

Lower Boise River 5-year Subbasin Assessment and TMDL Review

DO

dissolved oxygen

DOI

U.S. Department of the Interior

DWS

domestic water supply

EMAP

Environmental Monitoring and Assessment Program

EPA

United States Environmental Protection Agency

ESA

Endangered Species Act

F

Fahrenheit

FPA

Idaho Forest Practices Act

FWS

U.S. Fish and Wildlife Service

GIS

Geographical Information Systems

HUC

Hydrologic Unit Code

I.C.

Idaho Code

IDAPA

Refers to citations of Idaho administrative rules

IDFG

Idaho Department of Fish and Game

IDL

Idaho Department of Lands

IDWR

Idaho Department of Water Resources

INFISH

the federal Inland Native Fish Strategy

IRIS

Integrated Risk Information System

km

kilometer

km2

square kilometer

LA

load allocation

LC

load capacity

m

meter

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

m3

cubic meter

mi

mile

mi2

square miles

MBI

Macroinvertebrate Biotic Index

MGD

million gallons per day

mg/L

milligrams per liter

mm

millimeter

MOD*

Modified Communities (*not approved by EPA)

MOS

margin of safety

MRCL

multiresolution land cover

MWMT maximum weekly maximum temperature n.a.

not applicable

NA

not assessed

NB

natural background

nd

no data (data not available)

NFS

not fully supporting

NPDES

National Pollutant Discharge Elimination System

NRCS

Natural Resources Conservation Service

NTU

Nephelometric turbidity unit

ORV

off-road vehicle

ORW

Outstanding Resource Water

PACFISH

the federal Pacific Anadromous Fish Strategy

PCR

primary contact recreation

PFC

proper functioning condition xi

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

ppm

part(s) per million

QA

quality assurance

QC

quality control

RBP

rapid bioassessment protocol

RDI

DEQ’s River Diatom Index

RFI

DEQ’s River Fish Index

RHCA

riparian habitat conservation area

RMI

DEQ’s River Macroinvertebrate Index

RPI

DEQ’s River Physiochemical Index

SBA

subbasin assessment

SC

Seasonal Cold Water Communities

SCR

secondary contact recreation

SFI

DEQ’s Stream Fish Index

SHI

DEQ’s Stream Habitat Index

SMI

DEQ’s Stream Macroinvertebrate Index

SRP

soluble reactive phosphorus

SS

salmonid spawning

SSC

suspended sediment concentration in milligrams per liter

SSOC

stream segment of concern

STATSGO

State Soil Geographic Database

TDG

total dissolved gas

TDS

total dissolved solids

T&E

threatened and/or endangered species

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TIN

total inorganic nitrogen

TKN

total Kjeldahl nitrogen

TMDL

total maximum daily load

TP

total phosphorus

TS

total solids

TSS

total suspended solids

t/y

tons per year

U.S.

United States

U.S.C.

United States Code

USDA

United States Department of Agriculture

USDI

United States Department of the Interior

USFS

United States Forest Service

USGS

United States Geological Survey

WAG

Watershed Advisory Group

WARM

Warm Water Communities

WBAG

Water Body Assessment Guidance

WBID

water body identification number

WET

whole effluence toxicity

WLA

wasteload allocation

WQLS

water quality limited segment

WQMP

water quality management plan

WQRP

water quality restoration plan

WQS

water quality standard

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Executive Summary This document presents a five-year review of the Lower Boise River Subbasin Assessment (SBA) and Total Maximum Daily Loads (TMDLs) for bacteria and sediment. This review addresses the water bodies in the Lower Boise River Subbasin that are in Idaho’s current and most recent draft Section 4(a) of the Integrated Report. This five-year review has been developed to comply with Idaho Statute 39-3611 (7). The review describes current water quality status, pollutant sources, and recent pollution control efforts in the Lower Boise River Subbasin, located in southwest Idaho. The TMDLs subject to five-year review are shown in Table A. The initial SBA and TMDL for the mainstem and SBAs for the tributaries are available from the Department of Environmental Quality (DEQ) Web site at http://www.deq.state.id.us/water/data_reports/surface_water/tmdls/sba_tmdl_master_list.cfm and describe the physical, biological, and cultural setting; water quality status; pollutant sources; and previous pollution control actions in the subbasin. Based on the results of the five-year review, recommendations for the next (2010) Integrated Report are as follows: 

30 assessment units (AUs) listed in Section 4c (Rivers Impaired by Flow or Habitat Alteration)  7 AUs listed in Section 5 (Impaired Waters)  9 AUs listed in Section 3 (Unassessed Waters)  7 AUs de-listed for impairments listed in the draft 2008 Integrated Report  Develop 5 TMDLs for currently listed impairments.  1 AU listed in Section 2 (Supporting All Uses) Rationale for recommendations is provided in the discussion of each AU in this sections’ Summary of Decisions.

About Assessment Units Prior to 2002, impaired waters were defined as stream segments with geographical descriptive boundaries. In 2002, DEQ modified the structure and format of Idaho’s 303(d) list by combining it with the 305(b) report, which is required by the Clean Water Act (CWA) to inform Congress of the state of Idaho’s waters. This modification included identifying stream segments by assessment units (AUs) instead of non-uniform stream segments, and defining the use support of stream AUs by five categories, each of which is published as a section in the integrated report. AUs now define all the waters of the state of Idaho. These units and the methods used to describe them can be found in the Water Body Assessment Guidance, second edition (WBAG II) (Grafe, et al., 2002). AUs are groups of similar streams that have similar land use practices, ownership, or land management. Stream order, however, is the main basis for determining AUs— even if ownership and land use change significantly, an AU remains the same. Because AUs are an extension of water body identification numbers, and each water body has individual WQS, there is now a direct tie between AUs and water quality standards (WQS), so that beneficial uses defined in the WQS are clearly tied to streams on the landscape. To facilitate comparisons between the 1998 303(d) list and the 2002 Section 5 “impaired waters” category in the Integrated Report, a crosswalk from the 1998 303(d) list to the new

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AUs was included in the 2002 integrated report. A copy of the report is available from the DEQ Web site at http://www.deq.state.id.us/water/data_reports/surface_water/monitoring/2002.cfm#2002final. The boundaries from the 1998 303(d)-listed segments have been transferred to the new AU framework using an approach quite similar to how DEQ has been writing SBAs and TMDLs. All AUs contained in any listed segment were carried forward to the 2002 303(d) listings in Section 5 of the integrated report (DEQ, 2005). Any AU not wholly contained within a previously listed segment, but partially contained (even minimally), was also included on the 303(d) list. This was necessary to maintain the integrity of the 1998 303(d) list and continuity with the TMDL program. The Lower Boise River subbasin water bodies listed on the 2002 303(d) list are included in this report, but the review is focused on the draft 2008 status lists. When new monitoring data indicate full support, only the AU that the data represents will be removed (de-listed) from the 303(d) list (Section 5 of the integrated report).

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Figure A. Streams and assessment units in Lower Boise River HUC 17050114.

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TMDL Targets and Load Allocations The 1999 TMDL established targets for sediment and bacteria in the mainstem river with control monitoring for sediment at two locations (USGS gages at Middleton and Parma) and for bacteria at three locations (USGS gages at Glenwood, Middleton and Parma). Recognizing that sediment and bacteria loads in the mainstem river were most likely the result of cumulative effects of loads from influent sources such as tributaries and drains, load allocations (LAs) for sediment and bacteria were established at the mouths of 12 tributary and drain locations and 3 riparian corridors. Assigning LAs for tributaries and drains is not synonymous with listing those tributaries and drains as impaired for sediment and bacteria. The purpose of the LAs is to restore the listed waterbody (Lower Boise River) to beneficial use support status.

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Table A. 1999 TMDLs and correlating assessment units from 2002 Water Quality Standards revisions and associated load allocations, implementation activities and monitoring data. Stream Segment Assessment Description Unit Boise River 6th order 001_06 from Indian Creek to the mouth, and tributaries to the 6th order.

TMDL Lower Boise River TMDL (1999). Addendum (2008).

Snake RiverHells Canyon (2004).

Load Allocation

Implementation Plan

Target for TSS-50 mg/L for 60 days, 80 mg/L 14 days; 213 cfu/100 ml (geomean) fecal coliform

2003

242 kg/day (<0.07 mg/L) total phosphorus.

2007

Implementation Activities

Monitoring Data

Canyon County SCD, Conway Gulch, 141 BMPs; Dixie Slough, 75 BMPs.

Sediment, Bacteria, Temperature, Nutrients, Flow, DO, pH, BURP, Aquatic Biota

City of Caldwell low impact development demonstration

Sediment, Bacteria, Nutrients, DO, pH, Flow, Temperature

5.74 tons/day TSS; 129 LA in Lower cfu/100 ml (geomean) Boise River TMDL (1999). fecal coliform. Addendum (2008).

2003

Boise River 6th 005_06 order, and tributaries to 6th order, from Glenwood Bridge to Mason Creek.

Lower Boise River TMDL (1999). Addendum (2008).

Target for TSS-50 mg/L for 60 days, 80 mg/L 14 days; 354 cfu/100 ml (geomean) fecal coliform.

2003

Sediment, Bacteria, Nutrients, DO, pH, Temperature, BURP, Flow

Mason Creek source 006_02 to mouth.

LA in Lower Boise River TMDL (1999). Addendum (2008).

21.48 tons/day TSS; 50 cfu/100 ml (geomean) fecal coliform PCR; 200 cfu/100 ml (geomean) fecal coliform SCR.

2003

Sediment Bacteria, Nutrients, DO, pH, Temperature, BURP, Aquatic Biota

Indian Creek 4th order from Phyllis Canal to mouth.

002_04

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

Stream Segment Assessment Description Unit

TMDL

Load Allocation

February 2009

Implementation Plan

Implementation Activities

Monitoring Data

Fifteenmile Creek, 007_04 4th order and tributaries to the 4th order.

LA in Lower Boise River TMDL (1999). Addendum (2008).

18.02 tons/day TSS; 50 cfu/100 ml (geomean) fecal coliform PCR; 200 cfu/100 ml (geomean) fecal coliform SCR.

2003

Ada County SWCD Sediment, Bacteria, Fifteenmile Creek, Nutrients, DO, pH, Flow 34 BMPs

Boise River from Barber Dam to Glenwood Bridge.

011a_06

Lower Boise River TMDL (1999). Addendum (2008).

Target for TSS-50 mg/L for 60 days; 80 mg/L 14 days; 28 cfu/100 ml (geometric mean) fecal coliform.

2003

Downtown Boise Sediment, Bacteria, Nutrients, DO, pH, Flow, gray water Aquatic Biota recycling demonstration; Barber Park Living Roof demonstration.

Boise River between 011b_06 Lucky Peak outfall and Diversion Dam.

Lower Boise River TMDL (1999). Addendum (2008).

Target for TSS-50 mg/L for 60 days; 80 mg/L 14 days; 28 cfu/100 ml (geometric mean) fecal coliform.

2003

Sediment, Temperature, Flow, Aquatic Biota

Willow Creek, North 015_03 Fork Willow Creek, and unnamed tributaries.

2.28 tons/day TSS; 50 LA in Lower cfu/100 ml (geometric Boise River TMDL (1999). mean) fecal coliform. Addendum (2008).

2003

Sediment Bacteria, Nutrients, DO, pH, Temperature, BURP

Sand Hollow Creek

Snake RiverHells Canyon (2004).

2007

Sediment Bacteria, Nutrients, DO, pH, Temperature

017_06

Included in ungaged flows LA of 137 kg/day (<0.07 mg/L) total phosphorus.

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Key Findings The review process includes an evaluation of current data in accordance with the WBAGII (Grafe, et. al., 2002), to determine attainment status of beneficial uses for each AU. During the review process, some AUs were found to be impaired by one or more of the following: flow and habitat alteration, temperature, sediment, and bacteria. TMDLs are required for water bodies determined to be impaired by pollutants. However, impairments caused by non-pollutants, such as flow and habitat alteration, do not require a TMDL. Results of the review process for each AU are included in Table B and discussed in this section’s Summary of Decisions. Determination of beneficial use support is based on evaluation of Beneficial Use Reconnaissance Program (BURP) surveys, water quality data collected by DEQ or third parties, and a review of other relevant information as discussed in Section 3.

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Table B. Summary of assessment units, draft 2008 Integrated Report, existing TMDLs, and five-year review results. Assessment Unit (2008 draft Integrated Report)

Stream Segment Description

2008 Draft List Pollutant

Unnamed 1st and 2nd order tributaries to Boise River between Indian Creek and the mouth.

Temperature

001_06

Boise River 6th order from Indian Creek to the mouth, and tributaries to the 6th order.

Temperature

Add to Section 4c for flow and Paleo meanders of the Boise River, habitat alteration. modified by diversions and drains for agricultural uses. Diversions remove 76% of summer flow. Temperature and geomean bacteria data exceed criteria. Sediment data exceeds TMDL targets.

002_04

Indian Creek 4th order from Phyllis Canal to mouth.

Temperature, Bacteria

Data exceed TMDL targets for sediment and criteria for bacteria, and temperature. All other criteria are met.

Add to Section 5 for sediment. Schedule a TMDL for bacteria and temperature.

Confined channel and de-vegetated riparian zones in urban impact area.

Add to Section 4c for flow and habitat alteration.

Ephemeral or intermittent, channels with numerous dams.

Add to Section 3 as unassessed and collect data to determine use designation and status.

001_02

003_02

North Indian Creek, 1st and 2nd order.

Sediment, Bacteria, Nutrients

Summary of Data and Observations

Riparian area 2 and 3 from the TMDL, including paleo oxbow lakes of the Boise River. Channels have been constructed to irrigate and drain cultivated fields; remnant wetlands and ponds remain.

Recommended Changes to Next Integrated Report

Add to Section 3 as unassessed. Collect data to verify listed impairments. Add to Section 4c for flow and habitat alteration.

Add to Section 4c for flow and habitat alteration.

xxii

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit (2008 draft Integrated Report) 003_03

Stream Segment Description

2008 Draft List Pollutant

Indian Creek 3rd order, upstream of Sand Creek.

Sediment, Temperature, Nutrients

Summary of Data and Observations

BOR data indicates criteria and TMDL targets are met when flow is present. BURP data indicates dry streams for 2 out of 3 sampling events. Constructed flow controls, ephemeral and intermittent streams, many impoundments.

003a_04

Indian Creek 4th order from Sand Creek to Phyllis Canal.

Sediment, Temperature, Unknown, DO

Data exceed criteria for temperature. All other criteria are met. Channelized, irrigation diversions, wastewater drains.

005_02

First and second order unnamed streams or tributaries to the Boise River from Glenwood Bridge to Mason Creek.

Secondary or abandoned channels and cutoff meanders of the mainstem Boise River, modified for agricultural uses (Miller canal) or urban development. Numerous diversions and drains, two large gravel mines.

xxiii

February 2009

Recommended Changes to Next Integrated Report

De-list for sediment, temperature, nutrients.

Add to Section 4c for flow and habitat alteration. De-list for sediment, unknown and DO. Schedule a temperature TMDL. Add to Section 4c for flow and habitat alteration. Add to Section 3 as unassessed and Section 4c for flow and habitat alteration. Collect data to determine uses and water quality status.

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit (2008 draft Integrated Report) 005_06

006_02

007_02

007_04

Stream Segment Description

2008 Draft List Pollutant

Boise River 6th order, and tributaries to 6th order, from Glenwood Bridge to Mason Creek.

Temperature

Mason Creek source to mouth.

Sediment, Unknown, DO, Nutrients

Summary of Data and Observations

February 2009

Recommended Changes to Next Integrated Report

Data indicate temperature exceeds criteria; and bacteria exceeds criteria and TMDL targets. Confined channel, diversions, streamside rapid infiltration basins/impoundments, industrial activity, de-vegetated riparian zone, irrigation and industrial drains, urban development.

Add to Section 4c for flow and habitat alteration.

Data indicate sediment and bacteria exceed criteria and TMDL LAs. All other data is within criteria.

De-list for DO, nutrients and unknown. Add to Section 5 for sediment and bacteria.

Confined Channel, diversions, drains, devegetated riparian zone.

Add to Section 4c for flow and habitat alteration.

Fifteenmile Creek, 1st and 2nd order and tributaries.

Data for bacteria exceed criteria and sediment exceeds TMDL targets.

Add to Section 5 for bacteria and sediment.

Channel is constructed, or modified to appear constructed, for agricultural purposes.

Add to Section 4c for flow and habitat alteration.

Fifteenmile Creek, 4th order and tributaries to the 4th order.

Data indicate sediment and bacteria exceed criteria, and all other criteria are met.

Add to Section 5 for sediment and bacteria.

Channel is constructed, or modified to appear constructed, for agricultural purposes.

Add to Section 4c for flow and habitat alteration.

xxiv

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit (2008 draft Integrated Report)

Stream Segment Description

008_02

1st and 2nd order tributaries to Tenmile Creek.

008_03

Third order Tenmile Creek.

2008 Draft List Pollutant

Bacteria, Unknown, Nutrients

Summary of Data and Observations

Blacks Creek 1st and 2nd order.

Habitat Alteration

Recommended Changes to Next Integrated Report

Ephemeral or intermittent channels, one spring and wetland. Several dams, 14 rapid infiltration basins near industrial sites, sand/gravel mines, isolated cultivated agricultural sites.

Add to Section 4c for flow and habitat alteration.

Data indicate sediment and bacteria exceed criteria, and all other criteria are met.

De-list for unknown and nutrients. Add to Section 5 for sediment. Schedule a TMDL for bacteria.

Numerous dams and reservoirs, and riparian modification for agriculture. 009_02

February 2009

Intermittent and ephemeral streams, dams and flow controls.

Add to Section 4c for flow and habitat alteration. Add to Section 3 as unassessed. Collect data to determine existing uses and water quality status. Add to Section 4c for flow alteration.

009_03

Blacks Creek 3rd order.

Habitat Alteration

Intermittent flow, flow control structures. Removed from BOR’s management plan because of poor storage potential and flow conditions. Reservoir is managed by IDFG.

xxv

Add to Section 3 as unassessed. Collect data to identify existing uses and water quality status. Add to Section 4c for flow alteration.

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit (2008 draft Integrated Report) 010_02

Stream Segment Description

2008 Draft List Pollutant

Fivemile Creek 1st and 2nd order.

Bacteria

Summary of Data and Observations

No data to support listing for bacteria. Intermittent and ephemeral channels. Stream has been modified to support canal system, parts of channel completely obscured by ag/urban development.

010_03

Fivemile Creek 3rd order.

Unknown, DO, Nutrients, Habitat Alteration

Data indicate exceedance of sediment and bacteria criteria.

Channelization for ag/urban development. 011a_02

1st and 2nd order tributaries to Boise River from Barber Dam to Glenwood Bridge.

011a_06

Boise River from Barber Dam to Glenwood Bridge.

Ephemeral or intermittent streams, a few small springs, dams and impoundments. Remnant rapid infiltration basins on banks of Boise River. Streams are not tributaries to the river. Temperature

February 2009

Recommended Changes to Next Integrated Report

Add to Section 3 as unassessed. Collect data to determine water quality status. Add to Section 4c for flow and habitat alteration. De-list for DO, nutrients and unknown. Add to Section 5 for sediment and bacteria. Add to Section 4c for flow alteration. Add to Section 4c for flow and habitat alteration.

Temperature criteria for salmonid spawning are exceeded every spring and most fall months. Criteria for pH, sediment, bacteria, DO, and ammonia are met. Flow control structures and diversions, near-stream impoundments, removal of riparian vegetation, wastewater drains. Includes Riparian area 1 from the TMDL.

xxvi

Add to Section 4c for flow and habitat alteration.

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit (2008 draft Integrated Report)

Stream Segment Description

2008 Draft List Pollutant

Dams and impoundments in the headwaters and near the valley floor. The only tributary to the river is at the base of the dam and may flow in response to that structure.

011b_02

1st and 2nd order streams and tributaries near outfall of Lucky Peak Dam.

011b_06

Boise River between Lucky Peak outfall and Diversion Dam.

Flow Alteration

Stewart Gulch, Cottonwood and Crane Creeks, 1st and 2nd order.

Habitat Alteration

012_02

Summary of Data and Observations

Stewart Gulch, Cottonwood and Crane Creeks, 3rd order to mouth.

Flow control structures, diversions and urban development have modified habitat.

Habitat Alteration

Recommended Changes to Next Integrated Report

Add to Section 4c for flow and habitat alteration.

Data indicate that criteria area met for temperature, pH and DO.

Cottonwood Creek is intermittent, based on USGS recent flow records for AU 012_03. Springs are developed and impounded, or diverted from natural channels. Flood control structures—sediment and overflow basins-- dating from the early 1900’s prevent mass wasting and reduce sediment loads to the river.

012_03

February 2009

Streams are modified with flood control structures and diversions. Flow is directed through pipes and flumes to the Boise River.

xxvii

Add to Section 4c for habitat alteration. Add to Section 3 as unassessed. Collect data to determine existing uses and water quality status. Add to Section 4c for flow alteration.

Add to Section 3 as unassessed. Collect data to determine existing uses and water quality status. Add to Section 4c for flow alteration.

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit (2008 draft Integrated Report)

Stream Segment Description

2008 Draft List Pollutant

Summary of Data and Observations

February 2009

Recommended Changes to Next Integrated Report

013_02

1st and 2nd order Dry Creek and tributaries.

Flow control structures and reservoirs in tributaries to Currant Creek.

Add to Section 4c for flow alteration.

013_03

3rd order Dry Creek and tributaries.

Data indicate that all criteria are met.

Add to Section 2 as supporting presumed uses.

4th order Dry Creek.

Flow control structures, channel modification, ag/urban development, gravel mine, and numerous impoundments.

Collect data to determine existing uses and water quality status.

Flow control structures and channel modifications to accommodate agriculture.

Collect data to determine existing uses and water quality status.

013_04

014_02

Flow control structures and channel modification to accommodate agriculture and urban development.

Big/Little Gulch Creek Complex

Add to Section 4c for flow and habitat alteration.

Add to Section 4c for flow and habitat alteration. 015_02

015_03

South Fork Willow Creek.

Willow Creek, North Fork Willow Creek, and unnamed tributaries.

Habitat Alteration, Temperature

Temperature, Habitat Alteration

Ephemeral or intermittent streams.

Collect data to determine existing uses and water quality status.

Flow control structures and impoundments.

Add to Section 4c for flow alteration.

Data indicate bacteria exceeds criteria and TMDL targets, and all other criteria are met.

De-list for temperature. Add to Section 5 for bacteria.

Channelized for ag/urban development, dewatered stream segments.

Add to Section 4c for flow alteration.

xxviii

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit (2008 draft Integrated Report) 016_02

Stream Segment Description

2008 Draft List Pollutant

Summary of Data and Observations

Appears to drain to the Payette River subbasin.

Langley/ Graveyard Gulch complex

February 2009

Recommended Changes to Next Integrated Report

Initiate review to determine possibility that landforms drain to HUC 17050122. Collect data to determine existing uses and water quality status.

Flow control structures and channel modification to accommodate agriculture. 016_03

017_02

017_03

Langley/ Graveyard Gulch complex

Sediment, Unknown, Nutrients, DO

1st and 2nd order Sand Hollow Creek and tributaries. Sand Hollow Creek 3rd order and tributaries

Add to Section 4c for flow and habitat alteration.

Most streams are ephemeral, 3 or 4 springs, no defined natural stream channels. No data to support listing.

Add to Section 3 as unassessed. Collect data to determine existing uses and water quality status.

Constructed and modified channels to accommodate agriculture.

Add to Section 4c for flow and habitat alteration.

Data indicate all criteria are met.

Sediment, Unknown, DO

Constructed and modified channels to accommodate agriculture.

Add to Section 4c for flow and habitat alteration.

Data indicate sediment exceeds TMDL targets. All other criteria are met.

De-list for DO and unknown. Schedule a sediment TMDL.

All streams are modified to facilitate agriculture.

Add to Section 4c for flow and habitat alteration.

xxix

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit (2008 draft Integrated Report) 017_06

Stream Segment Description

2008 Draft List Pollutant

Sand Hollow Creek

Sediment, Nutrients, DO, Unknown

Summary of Data and Observations

Data indicate that bacteria exceed criteria and sediment exceeds TMDL targets and criteria. Channelized, flow control structures, impoundments, diversions, and irrigation drains.

xxx

February 2009

Recommended Changes to Next Integrated Report

Add to Section 5 for sediment and bacteria. Add to Section 4c for flow and habitat alteration.

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Summary of Recommendations Because the draft 2008 Integrated Report was not approved before development of this review, the final 2008 Integrated Report may not reflect recommendations made in this report. All recommendations for the next Integrated Report refer to the 2010 Integrated Report. The following paragraphs are brief explanations of the recommendations summarized in Table B. Because all of the AUs discussed in this review are in the Lower Boise River subbasin, (HUC 17050114) the AUs will be referred to by the numerical suffix assigned to each AU in Idaho’s WQS. For example, the AU identified in Idaho WQS as ID17050114SW001_02 is abbreviated to 001_02. The following paragraphs are brief explanations of the beneficial use attainment status of each AU and the rationale used in offering recommendations for the next integrated report. Designated beneficial, existing, and presumed uses; WQS; and criteria for each AU are defined and summarized in Section 3 of this document. Some AUs received LAs in the TMDL because it was determined that the AU may be contributing, in a cumulative manner, to impairment of the stream segment of concern to the TMDL. An LA is not equivalent to a listing of impairment. 001_02 This AU includes 2 unnamed 1st order tributaries to the Boise River between Indian Creek and the mouth (including Riparian Area 2 and 3 of the TMDL) and is in Section 5 of the draft 2008 303(d) list for temperature. Beneficial uses are not designated and are presumed to meet cold water aquatic life (COLD) and primary and secondary contact recreation (PCR/SCR) uses. A review of satellite photo images from 2006 indicate that this AU is primarily remnant channels and oxbows of the Boise River that have been modified to irrigate and drain agricultural lands surrounding a large wetland. No temperature data is available to verify the listing in the draft 2008 Integrated Report. This AU should be added to Section 3 as unassessed and listed in Section 4c for flow and habitat alteration. Data should be collected to determine appropriate use designation and water quality status. 001_06 This AU includes the Boise River 6th order segment from Indian Creek to the mouth and unnamed tributaries to the 6th order segment. The designated uses for this AU are COLD and PCR and it is listed in the draft 2008 Integrated Report for temperature and has approved TMDLs for sediment and bacteria (DEQ, 1999). There are four control monitoring locations for the TMDL in this AU. Data has been collected from three of these locations in the past five years. The WQS for PCR have changed since the TMDLs were developed to an E. colibased standard for bacteria. Water District 63 controls flows through diversions and drains. Diversions total 1,600 cfs (76%) in an average July and drains are not monitored. Numerous canals and drains have been constructed and urbanization has resulted in modified channels throughout the AU.

xxxi

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

The U.S. Geological Survey (USGS) and the City of Boise have collected water quality data over the past five years that indicate the temperature of the Boise River in this AU exceeds criteria and geomean bacteria results exceed criteria. Two drains have been monitored for water quality: Dixie Drain and Conway Gulch. Data from these drains indicate temperature, sediment, and instantaneous bacteria criteria are exceeded; and phosphorus concentrations may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. Conway Gulch contributes more sediment and phosphorus than Dixie Drain and Dixie Drain contributes more bacteria than Conway Gulch. Sediment and bacteria LA targets established in the TMDL (DEQ, 1999) have not been achieved in this AU. This AU should be listed in Section 4c of the next Integrated Report for flow and habitat alteration. 002_04 This AU includes Indian Creek 4th order from Phyllis Canal to the mouth, Caldwell Highline Canal and Notus Canal. The designated uses are COLD and SCR and the AU is listed as impaired by temperature and bacteria in the draft 2008 Integrated Report. There is one control monitoring location in this AU for the TMDL and an LA for bacteria and sediment at the confluence with the Boise River. The WQS for SCR have changed since the TMDLs were developed, to an E. coli-based standard for bacteria. The stream has been straightened and confined and the riparian zone has been de-vegetated through the urban area. Agricultural drains and industrial and municipal effluent contribute to streamflow in this AU. The USGS and the Idaho State Department of Agriculture (ISDA) have collected water quality data from the control monitoring location over the past five years and reported results indicate that instantaneous bacteria and sediment criteria and TMDL targets are exceeded in this AU. There are also sediment plumes from the confluence into the Boise River visible in satellite images. Phosphorus data indicate that concentrations may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. Dissolved oxygen (DO) and pH are within criteria. The city of Nampa collected data above and below the WWTP from 2003 through 2007 in compliance with permit requirements. The data indicate that sediment, DO and pH are within criteria at the WWTP. Temperature criteria is exceeded in summer and fall months upstream of the WWTP. Because the temperature data collected by the USGS in 2005 was always collected in the morning and there are only 5 data points in that dataset, the data from the City of Nampa was more useful in making a determination for temperature in this AU. This AU should be listed in Section 5 for sediment, listed in Section 4c for flow and habitat alteration and a TMDL for bacteria and temperature should be scheduled.

xxxii

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

003_02 This AU includes North Indian Creek and 1st and 2nd order streams and tributaries. Slater Creek, Cow Creek, Sheep Creek, Ridenbaugh Canal, North Indian Creek, West Fork Slater Creek, Sand Creek and East Fork Slater Creek are in this AU. Beneficial uses are not designated and are presumed to meet COLD and PCR/SCR uses. The AU is listed in the 2008 draft Integrated Report for sediment, bacteria and nutrients. There is no evidence of anything more than ephemeral flow east of Pleasant Valley Road, in Ada County. Some evidence of intermittent flow is present between Pleasant Valley Road and South Cole Road, in Ada County. There are three flow control structures in Caldwell Draw and one in Slater Creek. East of South Cole Road, North Indian Creek is impounded, with no observed flow below the dam. There is no evidence of flow in the channel west of the impoundment until Cloverdale Road, where another large impoundment has been constructed in the stream channel just south of Kuna-Mora Road, on the east side of Cloverdale Road. North of Kuna-Mora Road the channel of North Indian Creek has been obliterated by cultivated fields, and meander scars are still visible in satellite images. Several impoundments have been constructed throughout the AU, and very little water is visible in the basins. Water quality data is not available for this AU and attempts to collect BURP data in 2007 failed due to dry stream conditions. Based on a review of available data, it is recommended that this AU be scheduled for a thorough assessment of existing conditions to determine correct designation of beneficial uses and water quality status. This AU should be listed in Section 3 as unassessed and Section 4c for flow and habitat alteration in the next Integrated Report. 003_03 This AU includes the 3rd order of Indian Creek, upstream of Sand Creek (including Indian Creek Reservoir), 3rd order of North Indian Creek, Sand Creek and unnamed tributaries. Indian Creek Reservoir was constructed before the existence of federal land management agencies and is managed by the Idaho Department of Fish and Game (IDFG) as a warm water fishery. The designated uses of this AU are COLD and SCR and it is listed in the draft 2008 Integrated Report for sediment, temperature and nutrients. Some unnamed streams, and possibly a portion of Indian and North Indian Creek, may be intermittent. In addition to numerous small impoundments on Indian Creek, there are three dams and two impoundments in Caldwell Draw (between Sheep and Indian Creeks) and one in Sheep Creek that appear to capture all available surface water. The IDFG frequently promotes salvage fishing from Indian Creek Reservoir in dry years and waits until a relatively wet year to restock the reservoir. The reservoir was classified by the IDFG as “dry” from 2001 through 2006. In 1999, the Bureau of Reclamation (BOR) collected water quality data from the inlet of the reservoir and from Indian Creek above the confluence with the New York Canal. BOR data indicate that criteria and TMDL targets for the Lower Boise TMDL are met at the sample

xxxiii

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

locations when flow is present. While the data is too old to be used for use determination in accordance with WBAG II (Grafe, et al., 2002), it can be used as Tier II data. It is recommended that this AU be de-listed for sediment, temperature and nutrients, assessed for use modification to MOD (not yet approved by EPA) and SCR and listed in Section 4c of the next Integrated Report for flow alteration. 003a_04 This AU includes Indian Creek 4th order from Sand Creek to Phyllis Canal and tributaries to the 4th order segment. The designated uses of this AU are COLD, salmonid spawning (SS) and SCR, and it is listed in the draft 2008 Integrated Report for sediment, temperature, DO and unknown. Sand and North Indian Creeks and unnamed tributaries appear to be ephemeral streams. Some unnamed streams, and possibly a portion of North Indian Creek, may be intermittent. There is a dam and a reservoir at the confluence of Sand and Indian Creeks and numerous channel modifications and impoundments in Indian Creek downstream of Sand Creek. DEQ collected BURP data (including fish and macroinvertebrate data) from this AU in 2003 that resulted in a low score and a determination that aquatic life beneficial uses are not supported in this AU (BURP Site ID 2003SBOIA051). DEQ also collected data in 2008 which indicate that water temperature in the spring exceeds criteria and one E. coli sample exceeded the single sample criteria, but no geomean data has been collected. All other data are within criteria. This AU should be de-listed for sediment, DO and unknown; scheduled for a temperature TMDL and listed in Section 4c for flow and habitat alteration in the next Integrated Report. 005_02 This AU includes the 1st and 2nd order unnamed streams or tributaries to the Boise River from Glenwood Bridge to Mason Creek, and the Miller canal. The beneficial uses are not designated and are presumed to support COLD and SCR/PCR uses. The AU is listed in the draft 2008 Integrated Report as unassessed. There is no water quality data for this AU and a review of satellite images indicates that these streams are secondary or abandoned channels and cut-off meanders of the mainstem Boise River that have been modified for agricultural uses or urban development. There are numerous diversions and drains and two large gravel mines in this AU and the land uses are cultivated agriculture, industrial and suburban. This AU should be added to Section 3 as unassessed, listed in Section 4c of the next Integrated Report for flow and habitat alteration and should be assessed to determine appropriate beneficial use designation and water quality status. 005_06 This AU includes Boise River 6th order, from Glenwood Bridge to Mason Creek and unnamed tributaries to the 6th order mainstem river, including the Phyllis Canal. The designated uses of this AU are COLD, SS and PCR and it is listed in the draft 2008

xxxiv

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Integrated Report as impaired by temperature. The mainstem river in this AU has approved TMDLs for sediment and bacteria. There are 10 TMDL control monitoring locations in this AU and data has been collected from five of these in the past five years. Discharge (flow volume), suspended sediment and bacteria data have been collected from two control monitoring locations by the USGS and ISDA between 2003 and 2008. The implementation plan specified plans for geomean bacteria data to be collected at control monitoring locations to determine compliance with the TMDL and geomean data was collected by the city of Boise in 2005. In addition to the constituents monitored for existing TMDLs, the city of Boise has collected continuous temperature data from the Boise River control monitoring location from 2003 to 2008. The perennial streams in this AU have been modified to facilitate agricultural activities with numerous diversions and drains and urban development has encroached into the floodplain of the mainstem river and has fostered devegetation of riparian zones along deepened and channelized streams. Between Glenwood Bridge and Parma, 76 to 89% of the flow is diverted every irrigation season, with an estimated 50% of that flow returning to the mainstem river between Star and Caldwell (BOR, 2008). Results of data collection reported by the USGS and the City of Boise indicate that geomean bacteria criteria are exceeded in the Boise River above Middleton and near Caldwell. Singlesample (instantaneous) bacteria criteria are exceeded in Mill Slough, but no geomean samples have been collected. Temperature data reported by all data collection agencies indicate that temperature criteria for SS are exceeded in the mainstem Boise River above Middleton every spring, and some years in the fall months. This pattern is evident from data collected at Mill Slough also. This AU should be listed in Section 4c of the next Integrated Report for flow and habitat alteration. 006_02 This AU includes Mason Creek from source to mouth, including Kuna Canal, New York Canal, Mason Slough and Mason Creek Feeder. It is designated for beneficial uses of MOD (not yet approved by EPA) and SCR and is listed in the draft 2008 Integrated Report for sediment, unknown and DO. This AU has LAs and two control monitoring locations for sediment and bacteria in the TMDL, at the confluence with the Boise River. The stream channel is visibly confined with numerous diversions and drains and the riparian zone has been de-vegetated to allow for urban development. The USGS and ISDA have collected data from one TMDL control location between 2003 and 2008 and DEQ collected BURP data from this AU in 2003 (BURP Site ID 2003SBOIA050). Based on the sample results reported by the data collection agencies, sediment and bacteria exceed criteria and TMDL targets. Reported values of DO and temperature are within criteria. The BURP scores, which include fish and macroinvertebrate data, were low and resulted in a determination that aquatic life and recreation beneficial uses are not supported in this AU.

xxxv

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

In the next Integrated Report, this AU should be de-listed for DO and nutrients, listed in Section 5 for bacteria and sediment and listed in Section 4c for flow and habitat alteration. 007_02 This AU includes the first and second order unnamed streams in the Fifteenmile Creek watershed. Beneficial uses are not designated and are presumed to meet COLD and SCR/PCR uses. The AU is listed in the draft 2008 Integrated Report as unassessed. This AU begins at the confluence of Tenmile and Fivemile Creeks, near the intersection of Linder and Franklin roads in Ada County and parallels the Highline Canal. The ISDA collected water quality data from this AU in 2008 and Tenmile and Fivemile Creeks are listed in the draft 2008 Integrated Report as impaired for bacteria and nutrients. This stream is a constructed channel or has been modified by agriculture and urban activities so that it appears to be entirely constructed. Results of data collected by the ISDA indicate that single-sample (instantaneous) bacteria criteria are exceeded more than 50% of the time, but no geomean samples have been collected. Results of suspended sediment analyses indicate that short-term and long-term TMDL targets are exceeded in this AU and criteria appear to be exceeded. Phosphorus concentrations may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. All other criteria appear to be met. Based on the information reviewed for this report, this AU should be listed in Section 5 for sediment and bacteria and Section 4c of the next Integrated Report for flow and habitat alteration. This AU should also be assessed for appropriate designation of uses. 007_04 This AU includes the 4th order of Fifteenmile Creek and unnamed tributaries. It is designated for beneficial uses of MOD (not yet approved by EPA) and SCR and is listed in the draft 2008 Integrated Report as unassessed. LAs for sediment and bacteria were assigned to one location in this AU with one control monitoring location. Water quality data is available for this AU and Tenmile and Fivemile Creeks (headwater source) are listed in the draft 2008 Integrated Report as impaired for bacteria and nutrients. This stream is a constructed channel or has been modified by agriculture and urban activities so that it appears to be entirely constructed. There are at least four diversions and numerous drains in this AU, which are used for agricultural purposes. Water quality data collected by the USGS in the summer of 2005 indicate that bacteria concentrations exceed the singlesample criteria, but geomean data has not been collected. All samples collected exceed the TMDL 60-day maximum target for suspended sediment, and phosphorus concentrations may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. All other reported values (temperature, pH and DO) are within standards.

xxxvi

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Based on information reviewed for this report, this AU should be listed in Section 5 for bacteria and sediment, and in Section 4c for flow and habitat alteration, in the next Integrated Report. 008_02 This AU includes 1st and 2nd order streams in the Tenmile Creek watershed. The beneficial uses are not designated and are presumed to be COLD and PCR/SCR. It is listed in the draft 2008 Integrated Report as unassessed. There is no water quality data for this AU but a review of satellite images indicates that most of the streams are ephemeral or intermittent, with the exception of one spring and wetland. There are several dams that appear to have dry or nearly dry impoundments, 14 rapid infiltration basins near industrial sites and at least nine sand/gravel mines. There are a few isolated cultivated agricultural sites. This AU should be listed in Section 4c of the next Integrated Report for flow and habitat alteration and data should be collected to determine the appropriate beneficial use designation and water quality status. 008_03 This AU includes the third order of Tenmile Creek, downstream of Blacks Creek Reservoir. It is designated for beneficial uses of MOD (not yet approved by EPA) and SCR and is listed in the draft 2008 Integrated Report for bacteria, nutrients and unknown. LAs for sediment and bacteria at the mouth of Tenmile Creek were established in the TMDL. There are numerous dams and impoundments and the riparian zone has been modified for agricultural uses. Data has been collected by the USGS four times between 2003 and 2008. Based on reported results, Tenmile Creek exceeds single-sample bacteria criteria and TMDL targets for sediment. Data to calculate bacteria geomean values has not been collected. Phosphorus concentrations may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. No other impairments are documented. It is recommended that this AU be de-listed for unknown and nutrients, listed in Section 5 for sediment and in Section 4c of the next Integrated Report for flow and habitat alteration. A bacteria TMDL should be scheduled. 009_02 This AU includes Blacks Creek 1st and 2nd order streams to the reservoir, Bryans Run and unnamed tributaries, and is listed in the draft 2008 Integrated Report for habitat alteration. Beneficial uses are not designated and the AU is presumed to meet COLD and PCR/SCR uses. A review of satellite images indicates that most of this AU is intermittent or ephemeral, with three pools in the main channel of Blacks Creek, but no flowing water. Bryans Run contains two constructed flow control features and three unnamed tributaries have

xxxvii

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

constructed impoundments, but no free-flowing water. Water quality data has not been collected from this AU in the past five years, and BURP samples from 1996 (1996SBOIA055) and 1998 (1998SBOIA006) indicate that dry stream conditions dominate this AU in the spring and summer months. This AU should be added to Section 3 as unassessed and listed in Section 4c for flow and habitat modification in the next Integrated Report. Data should be collected to determine appropriate beneficial use designation and water quality status. 009_03 This AU includes Blacks Creek 3rd order, which encompasses Blacks Creek Reservoir to the headwaters of Tenmile Creek. The AU is not designated and is presumed to meet beneficial uses of COLD and PCR/SCR. It is listed in the draft 2008 Integrated Report for habitat alteration. There are three dams and impoundments in this AU and flow appears to be ephemeral in most years and intermittent in years with above average precipitation. Blacks Creek Reservoir is fed by ground water and is owned by the Bureau of Land Management (BLM) and private parties and managed by IDFG. The IDFG has designated the area as an important bird area (IBA) and is working with the BLM Four Rivers Field Office and the Land Trust of Treasure Valley to recover and restore the ecology of the watershed. The watershed has been damaged by unregulated recreation use, which has resulted in refuse dumping, avian poaching, destructive off-road vehicle use, over-grazing, housing developments and invasive weeds. Water quality data has not been collected from this AU in the past five years and BURP data collected in 1998 (1998SBOIB005) reports conditions common to intermittent waters. Data should be collected to determine appropriate beneficial use designation and water quality status. This AU should be added to Section 3 as unassessed and listed in Section 4c for flow and habitat modification in the next Integrated Report. 010_02 This AU includes 1st and 2nd order Fivemile Creek, Eightmile Creek and unnamed tributaries and is intersected by Interstate 84 southeast of the city of Boise. Beneficial uses are not designated and are presumed to be COLD and PCR/SCR. The AU is listed in the draft 2008 Integrated Report for bacteria. Water quality data has not been collected from this AU since BURP surveys documented dry stream conditions in 1998 (1998SBOIB007). Satellite images indicate that except for one or two small springs, the streams are ephemeral and may flow intermittently to West Gowen Road, where Fivemile Creek intersects the New York Canal. West of the New York Canal, the stream channel flows during the irrigation season through a mix of urban and suburban private land parcels. The stream has been straightened and deepened to support the intricate subbasin canal system. There is no riparian vegetation in this AU and it is uncertain what the natural channel morphology may have been, absent the extensive modifications now present.

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Agriculture and urban development of the cities of Boise and Meridian have almost completely obscured the natural stream channels throughout the remainder of the AU, which ends near the intersection of Overland and S. Eagle roads in Ada County. Data should be collected from this AU to determine appropriate use designation and water quality status. This AU should be added to Section 3 as unassessed and listed in Section 4c for flow and habitat modification in the next Integrated Report. 010_03 This AU includes the 3rd order of Fivemile Creek, which is a brief stream segment from the confluence of Eightmile Creek to the confluence with Fifteenmile Creek. The designated beneficial uses of this AU are MOD (not yet approved by EPA) and SCR and it is listed in the draft 2008 Integrated Report for habitat alteration, DO and unknown pollutants. LAs for sediment and bacteria at the mouth of Fivemile Creek were established in the TMDL, but this stream was not listed as impaired when the TMDL was developed. DEQ collected BURP data in 2003 (2003SBOIA052) that resulted in a low score and a determination of non-support of beneficial uses. The stream was dry when BURP sampling was attempted in 2005 (2005SBOIP009) and 1996 (1996SBOIA042). The USGS collected water quality data in the summer of 2005 that indicate that Fivemile Creek exceeds singlesample bacteria criteria and TMDL targets for sediment. Geomean bacteria data has not been collected. Reported results of phosphorus concentrations may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. Data collected over the same time period indicate that Fivemile Creek does not exceed criteria for temperature, DO, or pH. The same alterations to the channel and riparian habitat that were discussed for AU 010_02 are evident in this AU. This AU should be de-listed for DO and unknown pollutants and listed in Section 5 for sediment and bacteria, and Section 4c for flow and habitat modification in the next Integrated Report. 011a_02 This AU includes Squaw Creek, Warm Springs Creek, Maynard Gulch and unnamed 1st and 2nd order streams north of the Boise River near Barber, Idaho. The beneficial uses are not designated and are presumed to be COLD and PCR/SCR. The AU is listed in the draft 2008 Integrated Report as unassessed. Water quality data has not been collected from this AU and satellite images indicate that except for a few small springs, the streams are ephemeral or intermittent. In drainages that appear to experience some surface water flow, there are three dams and impoundments near the valley floor. These structures function as flood control structures to prevent mass wasting in the foothills from delivering excessive sediment to the Boise River. There are remnant rapid infiltration basins on the banks of the Boise River.

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This AU should be listed in Section 4c of the next Integrated Report for flow and habitat alteration and data should be collected to determine the appropriate designated beneficial uses and water quality status. 011a_06 This AU includes the Boise River from Barber Dam to Glenwood Bridge, including Phyllis Canal and Riparian Area 1 in the TMDL. The designated beneficial uses of this AU are COLD, SS, PCR, domestic water supply (DWS) and special resources water (SRW), and it is listed in the draft 2008 Integrated Report for temperature. The TMDL established WLAs for sediment and bacteria at each point source, and LAs for bacteria at the control monitoring location at Glenwood Bridge (USGS site 13206000). The USGS collected instantaneous discharge data at three locations from 2003 through 2008, and during the same time period the city of Boise collected continuous water temperature and geomean bacteria data from three locations: Boise River at Glenwood Bridge, Boise River at Marden Bridge and Boise River at Veterans Parkway. Data collected at Glenwood Bridge indicate that sediment and bacteria targets were not exceeded between 2003 and 2008. Fish data from 2003 indicates that SS is an existing use in this AU. Temperature data indicate that criteria for SS are exceeded most years from May through July and again in October and November at all three locations monitored by the city of Boise. Instantaneous temperature data collected by the USGS indicate that criteria exceedance is an issue from May through July. The USGS collected benthic macroinvertebrate data at the control monitoring location, but not during the time of year that can be used to determine use attainment status. DO and ammonia concentrations were within criteria for all samples and the pH criterion was exceeded once between 2003 and 2008. Phosphorus data from this AU may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. Flow and habitat in this AU have been modified by dams, reservoirs, diversions, urban encroachment in the riparian zone and point and nonpoint source effluent. Water District 63 is responsible for managing diversions in the Boise River and in most years, 76 to 85% of the flow between Barber Dam and Glenwood Bridge is diverted from the mainstem (BOR, 2008). The TMDL targets for sediment and bacteria appear to be achieved in this AU. This AU should be listed in Section 4c for habitat and flow alteration in the next Integrated Report. 011b_02 This AU includes 1st order unnamed tributaries to the Boise River below Lucky Peak Dam outfall. The beneficial uses for this AU are not designated and are presumed to support COLD and PCR/SCR uses. The AU is listed in the draft 2008 Integrated Report as unassessed. Water quality data has not been collected from this AU and satellite images indicate that except for a few small springs, the streams are ephemeral or intermittent. In

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drainages that appear to experience some surface water flow, there are dams and impoundments in the headwaters and near the valley floor. The only tributary to the river is at the base of Lucky Peak Dam and may flow in response to that structure. Data should be collected from this AU to determine appropriate use designation and water quality status. This AU should be listed in Section 4c of the next Integrated Report for flow and habitat alteration. 011b_06 This AU includes the Boise River between Lucky Peak Dam outfall and Diversion Dam and the tributaries to this segment of the mainstem river. The designated beneficial uses for this AU are COLD, PCR, DWS, and SRW and it is listed in the draft 2008 Integrated Report as unassessed and impaired by flow alteration. Flows are controlled by the Army Corps of Engineers (ACOE) in accordance with contracts negotiated by the Bureau of Reclamation. Water quality data has been collected by the USGS from one location between 2003 and 2008. The TMDL targets for sediment and bacteria appear to be met, based on data collected from the Boise River at Diversion Dam. The city of Boise collected continuous temperature data from below the Lucky Peak Dam outfall and the USGS collected flow data from the same location and instantaneous water temperature from the Boise River near Diversion Dam. The data indicate that temperature, DO, and pH criteria are met in this AU. Ammonia, phosphorus and aquatic life data have not been collected. It is recommended this AU be de-listed for temperature and be listed in Section 4c of the next Integrated Report for habitat alteration. 012_02 This AU includes 1st and 2nd order streams (Stewart Gulch, Hulls Gulch; Fivemile, Picket Pin, Freestone, Crane, Warm Springs and Cottonwood Creeks) on the north side of the Boise River between AU 011b_02 and the Glenwood Bridge. This AU does not have designated uses and is presumed to meet the beneficial uses of COLD and PCR/SCR. It is listed in the draft 2008 Integrated Report for habitat alteration. Water quality data has not been collected from the AU since 1996, when BURP data was collected from Cottonwood Creek (BURP Site IDs 1996SBOIA015 and 1996SBOIB033). Water flow was so low (0.4 cfs) during the BURP surveys that data collection was annotated as incomplete. A survey of satellite images of the watershed indicates that most of the streams in this AU are intermittent, and there are a few springs and a couple of gravel/sand mines. Several watersheds have been developed for golf courses and subdivisions and all drainages have been either truncated or straightened and diverted south of Hill Road in the city of Boise. The city of Boise has installed several flood management structures in Cottonwood Creek, Hulls Gulch, Crane Creek and Stewart Gulch to prevent mass wasting, control flooding and

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reduce sediment loads into the Boise River. There are sediment and overflow basins in the foothills and pipes and flumes in the floodplain that route streamflow to the river. These structures date to the early 1900s through the 1990s and are maintained by the city on a regular basis (personal communication with J. Wiley, city of Boise, 2008). Data should be collected from this AU to determine appropriate beneficial use designation and water quality status. This AU should be listed in Section 3 as unassessed and in Section 4c for flow alteration of the next Integrated Report. 012_03 This AU includes 3rd order Cottonwood Creek (from Fivemile Creek to the mouth), tributaries to Cottonwood Creek, Farmers Union Canal and tributaries to the Boise River in the Cottonwood Creek watershed. Beneficial uses are not designated and are presumed to be COLD and PCR/SCR. The AU is listed in the draft 2008 Integrated Report for habitat alteration. Most of the streams in this watershed have been modified with flood control structures as described for AU 012_02 and flow through impoundments and pipes between the foothills and the river. BURP data was last collected in 1996 by DEQ (BURP Site ID 1996SBOIA014) and flow data has been collected by the USGS from 2002 to 2008. Flow data, and information from the city of Boise Public Works Department (J. Wiley, personal communication, 2008) confirms that Cottonwood Creek is intermittent, with flow occurring November through May in most years. This AU should be assessed in accordance with the WBAG II (Grafe, et. al., 2002) to determine appropriate use designation and water quality status. This AU should be listed in Section 3 as unassessed and in Section 4c for flow alteration in the next Integrated Report. 013_02 This AU includes 1st and 2nd order Dry Creek and tributaries. Shingle Creek, Currant Creek, Spring Valley Creek, Custer Creek, North Fork Daniels Creek, McFarland Creek, South Fork Daniels and Daniels Creek. Beneficial uses are not designated and presumed uses are COLD and PCR/ SCR. The AU is listed in the draft 2008 Integrated Report as unassessed. Water quality data has not been collected from this AU, but a survey of satellite images indicate that there are at least 12 dams and reservoirs/impoundments (most of them in Currant Creek) and the land use around most of the observable springs is residential. This AU should be assessed to determine appropriate beneficial use designation and water quality status and listed in Section 4c for flow and habitat alteration in the next Integrated Report. 013_03 This AU includes Dry Creek 3rd order and tributaries, from Daniel Creek to the confluence with Spring Valley Creek, including Currant Creek and Spring Valley Creek. The beneficial

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uses are not designated and are presumed to be COLD and PCR/ SCR. The AU is listed in the draft 2008 Integrated Report as unassessed. Based on a review of satellite images, most of the streams in this AU appear to be intermittent. Dry Creek and Spring Valley Creek appear to be perennial streams with irrigated cultivated fields filling the floodplain of both streams. The perennial streams appear to be confined and may have been deepened to facilitate agricultural land uses. The ISDA collected data this year (2008) and data indicate that the presumed beneficial uses are met. This AU should be added to Section 2, as supporting presumed uses, in the next Integrated Report. 013_04 This AU includes Dry Creek 4th order, and tributaries, from Spring Valley Creek to the confluence with the Boise River. The beneficial uses are not designated and are presumed to be COLD and PCR/ SCR. The AU is listed in the draft 2008 Integrated Report as unassessed. The watershed is sparsely populated, but almost all of the agriculture that requires irrigation occurs on the banks of the streams. A large gravel mine and numerous impoundments exist in the watershed. Close to the confluence with the Boise River. The city of Eagle has expanded and suburban neighborhoods almost fill the southeast half of the watershed with numerous canals and laterals transecting the perennial streams at several locations. Streams in the AU have been channelized to facilitate urban, agricultural, and industrial development. This AU should be assessed to determine appropriate beneficial use designation and water quality status and listed in Section 4c for habitat and flow alteration in the next Integrated Report. 014-02 This AU includes Big Gulch and Little Gulch Creeks, a complex of intermittent streams, and is listed in the draft 2008 Integrated Report as unassessed. Beneficial uses are not designated and are presumed to meet COLD and PCR/SCR uses. Water quality data has not been collected from this AU and a review of satellite images indicate that the streams are ephemeral or intermittent and have been modified by flow control structures. Big Gulch Creek and Woods Gulch each have two dams and reservoirs and one dam is in Little Gulch Creek. This AU should be assessed to determine appropriate beneficial use designation and water quality status and listed in Section 4c for flow and habitat alteration in the next Integrated Report.

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015_02 This AU includes 1st and 2nd order Willow Creek and tributaries. This includes Alkali, Schiller, North and South Fork Willow and Willow Creeks and Middleton Mill Ditch. The beneficial uses are not designated and are presumed to be COLD and PCR/SCR. The AU is listed in the draft 2008 Integrated Report for habitat alteration and temperature impairment. The streams in the AU appear to have ephemeral, hyporheic, or intermittent flow patterns and there is a history of frequent wildland fires. The ISDA has collected water quality data from this AU and BURP data was collected by DEQ in 1996 (1996SBOIA084), 2004 (2004SBOIAA004) and 2005 (2005SBOIA012). Attempts to conduct BURP surveys failed in 1996 because the stream channel was dry, failed in 2004 because access was denied by the landowner (who claimed the stream is always dry) and failed in 2005 because no streambed was visible and urban development was occurring at the sample location. Data collected by the ISDA is too old to be used to determine use attainment status, but indicates that the mainstem of Willow Creek in this AU is usually dry. North and South Fork Willow and Schiller Creeks have been modified by flow control structures and visibly straightened near cultivated fields. Three dams and impoundments are in the North Fork Willow Creek, two in Schiller Creek, and one in South Fork Willow Creek. This AU should be assessed to determine appropriate beneficial use designation and water quality status, listed in Section 3 as unassessed and listed in Section 4c for flow alteration in the next Integrated Report. 015_03 This AU includes the 3rd order of Willow Creek, North Fork Willow Creek and tributaries. The beneficial uses are not designated and are presumed to be COLD and PCR/SCR. The AU is listed in the draft 2008 Integrated Report for habitat alteration and temperature. This AU was assigned LAs for sediment and bacteria in the Lower Boise River TMDL and has one control monitoring location. A spring complex west of the junction of Pearl and Chaparral roads is visible from satellite images and the mainstem of Willow Creek has been relocated, straightened, and constricted west of the natural channel to accommodate cultivated agriculture. Riparian vegetation density increases and a braided channel reforms downstream of the irrigated fields and springs. Near Highway 16, the mainstem of Willow Creek has been straightened, confined, and possibly deepened to allow for agriculture and low-density suburban development. The stream channel appears to be dry in most places upstream of the intersection with the C-Line Canal, west of Blessinger Lane in Canyon County. Downstream of the canal, the stream channel appears to be one-third the width of the canal and riparian vegetation density varies from substantial to absent through the city of Middleton to the confluence with the Boise River, near Wiffin Lane. BURP data was collected in 1996 (1996SBOIA083, 1996SBOIA083) which resulted in documentation of a dry stream at the first site and a failing score at the second site. ISDA

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collected water quality data from this AU in 2008 and the USGS collected data in the summer of 2005 at the LA control monitoring location. Reported sample results indicate that this AU exceeds sediment targets and instantaneous bacteria criteria (geomean data has not been collected), and phosphorus concentrations may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. All other criteria are met. This AU should be de-listed for temperature and listed in Section 5 for bacteria, and Section 4c of the next Integrated Report for flow alteration. 016_02 This AU includes the Langley/ Graveyard Gulch complex, including the C-Line Canal West, and is listed in the 2008 draft Integrated Report as unassessed. Beneficial uses are not designated and are presumed to meet COLD and PCR/SCR uses. Most of the AU is in Gem County and the primary water bodies are constructed canals delivering water from the Payette River to this portion of the Lower Boise River subbasin. Water quality data has not been collected from this AU and a review of satellite images indicate that most natural stream channels in the AU are ephemeral in nature and most of the topography is actively cultivated. Features that resemble springs are evident in satellite images, but may be seeps from the canal system. This AU may actually contribute to the drainage area of the Payette River subbasin (17050122). Data should be collected to determine appropriate beneficial use designation and water quality status and this AU should be reviewed to determine correct HUC designation and listed in Section 4c of the next Integrated Report for flow and habitat alteration. 016_03 This AU includes Langley and Graveyard Gulch, ephemeral streams, and several springs north of the Sand Hollow Creek watershed (AU 017). The beneficial uses are not designated and are presumed to be COLD and PCR/SCR. The AU is listed in the draft 2008 Integrated Report for sediment, nutrients, DO and unknown pollutants. All visible natural drainages are either cultivated or channeled and diverted to support cultivation. Most springs have been developed and impounded and are not connected to other surface water bodies. Numerous constructed channels deliver water from the Payette River to irrigated crops and drain used water into AU 017. Water quality data has not been collected from this AU. Data should be collected to determine appropriate use designation and water quality status and this AU should be added to Section 3 as unassessed and listed in Section 4c of the next Integrated Report for flow and habitat alteration.

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017_02 This AU includes 1st and 2nd order streams in the Sand Hollow Creek watershed. This includes the D-Line Canal, Notus Canal and Farmers Cooperative Sebree Canal. The beneficial uses are not designated and are presumed to be COLD and PCR/SCR. The AU is listed in the draft 2008 Integrated Report as unassessed. This stream is a tributary to the Snake River, but is located in the Lower Boise River subbasin. It was not included in the TMDL and does not have LAs or targets for any pollutants. The largest water bodies are constructed canals and drains. Some natural channel remnant features are visible on satellite images, but most have been obliterated by cultivation and the ones that remain have been modified to facilitate agricultural practices. DEQ collected BURP data in 1996 (1996SBOIA081) and water quality data in 2008. Reported results indicate DO, bacteria, sediment, and temperature are within criteria. It is recommended that this AU be listed in Section 4c flow and habitat alteration. 017_03 This AU includes Sand Hollow Creek 3rd order, from the intersection of Farmway and Oasis roads in Canyon County to the intersection with Parma Drain, near Sharp Lane, in Canyon County. The designated uses of the AU are MOD (not yet approved by EPA) and SCR and it is listed in the draft 2008 Integrated Report for sediment, bacteria, DO, and unknown pollutants. This stream is a tributary to the Snake River, but is located in the Lower Boise River subbasin. It was not included in the TMDL and does not have LAs or targets for any pollutants. The channel has been modified to support agricultural canals, laterals, and drains, and the natural channel morphology is almost impossible to identify. There are approximately 6 flow control structures and at least 35 drains delivering agricultural effluent into Sand Hollow Creek in this AU. Upstream of Hwy 20/26, natural meanders are absent, with sinuosity and uncontrolled flow gradually reestablished downstream of Highway 20/26. DEQ is collecting water quality data in this AU this year (2008). Data indicate that one single-sample bacteria analysis exceeded criteria. Geomean bacteria data has not been collected and DO, pH, and temperature meet criteria. Sediment concentrations exceed TMDL targets and phosphorus concentrations may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. It is recommended that this AU be de-listed for DO and unknown, scheduled for development of a sediment TMDL, and listed in Section 4c for flow and habitat alteration in the next Integrated Report. 017_06 This AU includes 6th order Sand Hollow Creek from the intersection with Parma Drain to the boundary of the HUC. The designated uses of the AU are MOD (not yet approved by EPA) and SCR and it is listed in the draft 2008 Integrated Report for sediment, nutrients,

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DO, and unknown pollutants. This stream is a tributary to the Snake River, but is located in the Lower Boise River subbasin. This AU has TMDL LAs for total phosphorus in the Snake River-Hells Canyon TMDL (IDEQ, ODEQ, 2004). The channel has been straightened and confined to support agricultural land uses and there are at least two flow control structures and three drains delivering agricultural effluent into Sand Hollow Creek in this AU. Some natural sinuosity is preserved and the presence of water in abandoned channels, oxbows, and ponds indicates some hydraulic connection with shallow ground water. ISDA collected water quality data for this AU in 1998, 1999, and 2008. Data from 1998 and 1999 can be used as Tier II data for use attainment decisions. Data indicate that 85% of single-sample bacteria analyses exceed criteria, but geomean bacteria data has not been collected. Sediment concentrations exceed TMDL targets and appear to exceed criteria, and phosphorus concentrations may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. All other criteria are met. This AU should be listed in Section 5 for bacteria and sediment and Section 4c for flow and habitat alteration in the next Integrated Report.

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Section 1: Introduction The federal Clean Water Act (CWA) requires that states and tribes restore and maintain the chemical, physical, and biological integrity of the nation’s waters. States and tribes, pursuant to Section 303 of the CWA, are to adopt water quality standards necessary to protect fish, shellfish, and wildlife while providing for recreation in and on the nation’s waters whenever possible. Section 303(d) of the CWA establishes requirements for states and tribes to identify and prioritize water bodies that are water quality limited (i.e., water bodies that do not meet water quality standards). States and tribes must periodically publish a priority list (a “§303(d) list”) of impaired waters. For waters identified on this list, states and tribes must develop a total maximum daily load (TMDL) for the pollutants, set at a level to achieve water quality standards. Idaho Statute 39-3611(7) requires a five-year cyclic review process for Idaho TMDLs: The director shall review and reevaluate each TMDL, supporting subbasin assessment, implementation plan(s) and all available data periodically at intervals of no greater than five (5) years. Such reviews shall include the assessments required by section 39-3607, Idaho Code, and an evaluation of the water quality criteria, instream targets, pollutant allocations, assumptions and analyses upon which the TMDL and subbasin assessment were based. If the members of the watershed advisory group, with the concurrence of the basin advisory group, advise the director that the water quality standards, the subbasin assessment, or the implementation plan(s) are not attainable or are inappropriate based upon supporting data, the director shall initiate the process or processes to determine whether to make recommended modifications. The director shall report to the legislature annually the results of such reviews.

This report is intended to meet the intent and purpose of Idaho Statue 39-3611(7). The report documents the review of an approved Idaho TMDL and implementation plan and provides consideration of the most current and applicable information in conformance with Idaho Statute 393607, evaluation of the appropriateness of the TMDL to current watershed conditions, implementation plan evaluation, and consultation with the Watershed Advisory Group (WAG). An evaluation of the recommendations presented is provided. Final decisions for TMDL modifications are decided by the Department of Environmental Quality (DEQ) Director. Approval of TMDL modifications is decided by the U.S. EPA, with consultation by DEQ.

About Assessment Units Prior to 2002, impaired waters were defined as stream segments with geographical descriptive boundaries. In 2002, DEQ modified the structure and format of Idaho’s 303(d) list by combining it with the 305(b) report, which is required by the CWA to inform Congress of the state of Idaho’s waters. This modification included identifying stream segments by assessment units (AUs) instead of non-uniform stream segments, and defining the use support of stream AUs by five categories, each of which is published as a section in the integrated report. AUs now define all the waters of the state of Idaho. These units and the methods used to describe them can be found in the Water Body Assessment Guidance, second edition (WBAG II) (Grafe, et al., 2002). AUs are groups of similar streams that have similar land use practices, ownership, or land management. Stream order, however, is the main basis for determining AUs— even if ownership and land use change significantly, an AU remains the same. Because AUs are an extension of water body identification numbers, there is now a direct tie to the water quality standards (WQS) for each AU, so that beneficial uses defined in the WQS are clearly tied to streams on the landscape. To facilitate comparisons between the 1998 303(d) list and the 2002 Section 5 “impaired waters” category in the integrated report, a crosswalk from the 1998 303(d) list to the new AUs was included

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in the 2002 integrated report. A copy of the report is available from the DEQ Web site at http://www.deq.state.id.us/water/data_reports/surface_water/monitoring/2002.cfm#2002final. The boundaries from the 1998 303(d)-listed segments have been transferred to the new AU framework using an approach quite similar to how DEQ has been writing SBAs and TMDLs. All AUs contained in any listed segment were carried forward to the 2002 303(d) listings in Section 5 of the integrated report (DEQ, 2005). Any AU not wholly contained within a previously listed segment, but partially contained (even minimally), was also included on the 303(d) list. This was necessary to maintain the integrity of the 1998 303(d) list and continuity with the TMDL program. The Lower Boise River subbasin waterbodies listed on the 2002 303 (d) list are included in this report, but the review is focused on the draft 2008 status lists. When new monitoring data indicate full support, only the AU that the data represents will be removed (de-listed) from the 303(d) list (Section 5 of the integrated report). Because all of the AUs discussed in this review are in the Lower Boise River subbasin, (HUC 17050114) the AUs will be referred to by the numerical suffix assigned to each AU in Idaho’s WQS. For example, the AU identified in Idaho WQS as ID17050114SW001_02 is abbreviated to 001_02.

Subbasin at a Glance The Lower Boise River Subbasin is identified in the Idaho WQS as water body ID17050114, with 36 AUs and several site-specific WQS described under Section 150.12 (IDAPA 58.01.02). As described in the Lower Boise River TMDL (DEQ, 1999), the subbasin drains 1,290 square miles (mi2) of rangeland, forests, agricultural lands and urban areas into the Snake River at the confluence between the cities of Adrian and Nyssa, Oregon. The Lower Boise River is a 64-mile long seventh-order stream, which flows through Ada and Canyon counties. The subbasin also drains portions of Elmore, Gem, Payette, and Boise counties. The river aspect is northwest from Lucky Peak Dam outfall to the confluence with the Snake River near Parma, Idaho. There are at least seven 3rd order, one 4th order and one 6th order tributaries to the Lower Boise River (Figure 1). One other 6th order stream, Sand Hollow Creek, is included in the subbasin but drains to the Snake River approximately 1 mile north of the Lower Boise River confluence. The Lower Boise River subbasin was studied in 1995 by the Army Corps of Engineers (ACOE) to identify water resource problems and opportunities in the basin. The ACOE identified factors that contribute to beneficial use impairments of surface water and environmental degradation in the Lower Boise River subbasin as follows:

             

Numerous irrigation structures (more than 25 canals and ditches) Stormwater runoff Wastewater discharge Agricultural drains Ground water effluent Poor water quality of tributaries Reservoirs altering natural streamflow dynamics Erodible constructed levees Riparian corridor vegetation alteration (result of modified flow dynamics) Floodplain encroachment by urban development Ground water infiltration of municipal sewage systems Temporary earthen dams for irrigation diversions Absence of conservation plans Water supply and delivery problems 2

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Figure 1. Lower Boise River subbasin and beneficial use support status of waterbodies in the subbasin from the 2008 draft Integrated Report.

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While there are several reports describing the connectivity and interaction between shallow ground water and surface water in the Lower Boise River subbasin (Cosgrove and Taylor, 2007; IWWRI, 2004; USACE 1995, etc.), conjunctive use issues in the subbasin are outside the focus of this report and will not be addressed here. The population in Ada and Canyon counties is presently estimated at 532,337, with most of the population (359,035) residing in Ada County (US Census Bureau, 2008). The growth rate predicted by the ACOE was more than 3% per year, for an estimated population of 600,000 in Ada and Canyon counties by the year 2014. Ada County is 47% private and 45% federally owned, whereas Canyon County is 93% privately owned. Land use is divided between three dominant uses: rangeland (51%), irrigated crop and pasture (31%) and urban/suburban (18%), (Figure 2). There are 4,922 miles of paved and unpaved roads in the subbasin. During the past two decades, land use has been steadily converted from agricultural to urban uses. Between 1996 and 2004, a total of 10,930 acres were converted from agriculture to urban uses (IASCD, 2005).

Figure 2. Land use and 303(d)-listed streams in the Lower Boise River subbasin. Human activities have affected pollutant loads in the Lower Boise River subbasin since the mid-1800s, through modification of natural systems to accommodate permanent human residence and irrigation systems that were developed throughout the subbasin by the 1860s (ISHS, various works). There are at least 49 dams, regulated by the Idaho Department of Water Resources (IDWR) (Figure 3) and hundreds of diversions, not all of which are documented. In addition to regulated dams there are numerous other impoundments on private land with unknown water quality and storage capacity.

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Figure 3. Lower Boise River dams and diversions (canals) permitted through the Idaho Department of Water Resources (IDWR). 5

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Because the Lower Boise River is a tributary of significance to the Snake River, it received an LA for phosphorus in the Snake River-Hells Canyon (SR-HC) TMDL (IDEQ, ODEQ, 2004). A nutrient implementation plan for the Lower Boise River and major tributaries was completed in June 2008, revised in December 2008, and is available from the DEQ internet site at http://www.deq.state.id.us/water/data_reports/surface_water/tmdls/boise_river_lower/boi se_river_lower.cfm#plan2. This review will not address nutrients outside of presenting recent information from data collected within the past five years. Lake Lowell, also in the Lower Boise River Subbasin, is being addressed in a separate SBA/TMDL and will not be discussed in this document. The 2002 Integrated Report (DEQ, 2005) listed 23 AUs as impaired (Table 8) and the draft 2008 Integrated Report (DEQ, 2008) lists 24 AUs as impaired (Figure 1, Table 10). Section 2 of this report provides details of the existing TMDLs and Section 3 provides details regarding current designated beneficial uses for each AU and recent water quality data. Section 4 is a review of implementation activities throughout the subbasin in the past five years and Section 5 summarizes the five year review. The geology, climate, hydrology (ground and surface), channel morphology, and biologic characteristics of the basin were all discussed in detail in the Lower Boise River TMDL Subbasin Assessment, Total Maximum Daily Loads (DEQ, 1999). This review has yielded no new information on these topics, but will address subbasin characteristics that have changed since the TMDL was written: population, land use, point sources, WQS, and LAs assigned to the Lower Boise River and its tributaries since 1999.

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Section 2: TMDL Overview At the time the Lower Boise River TMDL (DEQ, 1999) was developed, four stream segments and seven tributaries were on the 303(d) list for a variety of pollutants (Table 1); including flow alteration, sediment, dissolved oxygen, oil and grease, nutrients, bacteria and temperature. Based on the results of the SBA, stream segments were delisted in 1998 for dissolved oxygen and oil and grease and TMDLs were developed for sediment and bacteria, with load allocations (LAs) for all major tributaries at their confluence with the Lower Boise River. A recommendation was made to evaluate a range of options for applying or developing alternative temperature criteria (DEQ, 1999).

Listed Waters The information in this section of the report is summarized or annotated from the original TMDL (DEQ, 1999) to describe the 1996 and 1998 303(d) listed stream segments and beneficial uses (Table 1), and WQS criteria associated with those stream segments. Load allocations established in the 1999 TMDL are shown in Table 2.

Table 1. Summary of §303(d)-listed stream segments in the Lower Boise River TMDL Subbasin Assessment, Total Maximum Daily Loads (DEQ, 1999). 1996 Designated Pollutant* Uses* Pollutants* (1996 (Stream Segment De-listed AU* Boundaries 303(d) list) Boundaries) SBA/TMDL in 1998 DWS, AG, CWB, SS, PCR, SCR Lucky Peak Sediment, (Lucky Peak Dam to Boise Dam to Barber Flow River Mile 50 Bacteria-1999, River 011b_06 Diversion Alteration (Veterans Parkway)) Addendum-2008 DWS, AG, CWB, SS, PCR, SCR (to Veterans Parkway); Barber Sediment, Ag, CWB, SS, PCR Boise 011a_06; Diversion to Sediment, DO, (Veterans Parkway DO, Oil & Bacteria-1999, Addendum-2008 River 005_06 Star Oil & Grease to Star) Grease Nutrients, Sediment, DO, Sediment, Bacteria-1999, Boise 005_06; Temperature, AG, CWB, PCR, River 001_06 Star to Notus Bacteria SCR DO Addendum-2008 Nutrients, Sediment, DO, Sediment, Bacteria-1999, Boise Notus to Snake Temperature, AG, CWB, PCR, River 001_06 River SCR DO Addendum-2008 Bacteria * AU – assessment unit, SBA/TMDL – subbasin assessment/total maximum daily load, DO – dissolved oxygen, DWS – drinking water source, AG – agriculture, CWB – cold water biota [now COLD -cold water communities, PCR – primary contact recreation, SCR – secondary contact recreation, SS – salmonid spawning Water Body Name

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table 2. Load Allocations, Lower Boise River 1999 TMDL Water Body Name Fivemile Creek Tenmile Creek Indian Creek

Boundaries

AU*

Pollutants* 1996 303(d) List

1996 Designated Uses* CWB, SCR

Headwaters to Fifteenmile Creek Headwaters to Fifteenmile Creek Indian Creek, Headwaters to New York Canal Indian Creek New York Canal to Boise River

010

003; 002

DO, Nutrients, Oil and Grease, Sediment

CWB, PCR

Mason Creek

Mason Creek

006

DO, Nutrients, Sediment

CWB, SCR

Sand Hollow Creek Blacks Creek

Sand Hollow Creek 017

009

DO, Nutrients, Sediment

CWB, SCR

Willow Creek

015

Unknown

CWB, SCR

Headwaters to Blacks Creek Reservoir Headwaters to Boise River

080 003

LAs in TMDL (1999)

DO, Nutrients, Sediment DO, Nutrients, CWB, SCR Sediment Nutrients, Sediment SS, CWB, PCR

Sediment- 5.74 Tons/day Bacteria- 50 (PCR; 200 (SCR)-geomean Sediment-21.48 Tons/dayBacteria- 50 (PCR; 200 (SCR)-geomean

CWB, SCR

Sediment-2.28 Tons/day- Bacteria- 50 (PCR; 200 (SCR)geomean

Cottonwood Headwaters to CWB, SCR 012 Unknown Creek Freestone Creek * AU – assessment unit, CWB- Cold Water Biota, SS-Salmonid Spawning, PCR-Primary Contact Recreation, SCR-Secondary Contact Recreation

Permitted Point Sources Point sources require a National Pollutant Discharge Elimination System (NPDES) permit from the EPA in order to discharge effluent into a surface waterbody. In 1999, there were relatively few permitted point sources in the subbasin (Table 3, Figure 4). These permits limited the concentration of sediment, bacteria, and in some cases, ammonia and temperature. WLAs from the TMDL were intended to be included in future NPDES permits in the subbasin.

Table 3. Municipal wastewater treatment plants (WWTP) and selected permitted point sources discharging to the Lower Boise River and its tributaries in 1998 (DEQ, 1999). Point Source Design/Permit

Flow (MGD*)

Receiving Water

City of Boise - Lander Street City of Boise - West Boise WWTP City of Meridian WWTP Star Water and Sewer District City of Nampa WWTP City of Middleton WWTP

15

Boise River Boise River, South Channel Fivemile Creek and Boise River Lawrence-Kennedy Canal Indian Creek Boise River

24 2.82 0.33 11.76 1.83

8

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Point Source Design/Permit City of Caldwell WWTP City of Wilder WWTP City of Notus WWTP City of Parma WWTP IDFG Fish Hatchery Armour Fresh Meats

Flow (MGD*)

February 2009

Receiving Water

8.48

Boise River Wilder Ditch Drain Conway Gulch Sand Hollow Drain Wilson Drain Indian Creek

0.075 0.056 0.31 20 0.475

* MGD – million gallons per day

Figure 4. Permitted point sources with wasteload allocations in the Lower Boise River Subbasin TMDL (DEQ, 1999).

Nonpoint Sources The identified nonpoint sources of sediment and bacteria pollution in the subbasin included agricultural activities, stormwater runoff, construction activity, septic systems and bank erosion. Irrigation, streambank trampling by livestock and construction activities were identified as primary sources of sediment. Construction activities and stormwater runoff have since been regulated to control pollution through federal NPDES permits. Bacteria sources were believed to be primarily from nonpoint sources such as septic systems, livestock operations and wildlife.

9

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Pollutant Targets Water Quality Criteria In 1998, Idaho WQS contained numeric and narrative criteria to protect beneficial uses. The following water quality criteria were applicable to the pollutants of concern listed on the 1996 and 1998 Section 303(d) lists for existing and designated uses on the Boise River at the time the TMDL (DEQ, 1999) was published.

Bacteria Both primary and secondary contact recreation beneficial uses have associated numeric criteria in Idaho’s WQS. Primary Contact Recreation (May 1 - September 30) fecal coliform bacteria colonies: 

may not exceed 500/100 ml at any time;



may not exceed 200/100 ml in more than 10% of the total samples taken over a thirty-day period; and



may not exceed a geometric mean of 50/100 ml based on a minimum of five samples taken over a thirty-day period (IDAPA 16.10.02.250.01.a).

Secondary contact recreation (all year) fecal coliform bacteria colonies: 

may not exceed 800/100 ml at any time;



may not exceed 400/100 ml in more than 10% of the total samples taken over a thirty-day period; and



may not exceed a geometric mean of 200/100 ml based on a minimum of five samples taken over a thirty-day period (IDAPA 16.01.02.250.01.b).

Sediment Sediment shall not exceed quantities specified in IDAPA 15.01.02.250, or, in the absence of specific sediment criteria, quantities that impair designated beneficial uses. Determinations of impairment shall be based on water quality monitoring and surveillance and the information utilized as described in Sub 350.02.b (IDAPA 16.01.02.200.08). The sediment target was established in the 1999 TMDL by a literature review and comparison with other states’ total suspended solids (TSS) criteria. It was found that no more than 80 mg/L TSS in a 14-day acute exposure would be protective of adult fish. The target of no more than 50 mg/L TSS in a 60-day chronic exposure would be protective of the eggs and larval stages of fish.

Turbidity For cold water biota, turbidity below any applicable mixing zone set by the Department of Health and Welfare, DEQ, shall not exceed background turbidity by more than 50 Nephelometric Turbidity Units (NTU) instantaneously, or more than 25 NTU for more than 10 consecutive days (IDAPA 15.01.02.250.02.c.iv).

Nutrients Surface waters of the state shall be free from excess nutrients that can cause visible slime growths or other nuisance aquatic growths impairing designated beneficial uses (IDAPA 16.01.02.200.06).

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Temperature For warm water biota (WWB), waters are to exhibit the following characteristics: Water temperatures of 33 °C or less with a maximum daily average no greater than 29 °C. (IDAPA 16.01.02.250.02.b.ii). For cold-water biota (CWB), waters are to exhibit the following characteristics: Water temperatures of 22 °C or less with a maximum daily average no greater than 19 °C. (IDAPA 16.01.02.250.02.c.ii). For salmonid spawning (SS), waters are to exhibit the following characteristics during the spawning and incubation period for the particular species inhabiting those waters: Water temperatures of 13 °C or less with a maximum daily average no greater than 9 °C. (IDAPA 16.01.02.250.02.d.ii). The time periods for salmonid spawning that applied to species in the Boise River are: rainbow trout, January 15 to July 15; brown trout, October 1 to April 1; mountain whitefish, October 15 to March 15.

Control/Monitoring Points The group originally known as the Lower Boise River Water Quality Plan (LBRWQP) (the WAG) contracted the USGS to continue collecting physical, chemical and biological data from the river and selected tributaries. The WAG selected 17 control monitoring locations for sediment and 18 control monitoring locations for bacteria. The mainstem river had two monitoring locations for sediment and three for bacteria. The USGS gages on the Boise River at Middleton and Parma were designated as control monitoring locations for sediment and the USGS gage at Glenwood Bridge was added to the sediment locations as a control location for bacteria monitoring. The other locations were distributed throughout the subbasin at the mouths of tributaries and drains. The city of Boise, city of Nampa, Idaho State Department of Agriculture (ISDA), Bureau of Reclamation (BOR), LBRWQP, and DEQ have collected water quality data or have contracted to have water quality data collected at many locations throughout the subbasin during the past five years. Data not collected by DEQ was retrieved from public databases or provided by other agencies as a professional courtesy. A full list of data sources is provided in Table 12 and data is provided in Appendix C. Water quality monitoring data required as a part of EPA-administered NPDES permits include the points of discharge for each permitted point source and are evaluated in the absence of other relevant data for the AU of interest.

Load Capacity Load capacities for the Lower Boise River were calculated, using Middleton and Parma as control points, based on analysis of low, median, and high-flow years. Different land uses, land management practices, and flow control management (dam regulation and irrigation flows), determine the capacity of the Boise River to assimilate pollutants.

Sediment The surrogate measure for sediment pollution in the Lower Boise River is total suspended sediment (TSS or SSC). Only high flows and irrigation flows were considered in calculating load capacities because data indicated that TSS did not exceed maximum concentration thresholds for protection of beneficial uses and did not require an allocation during low flows. In the Lower Boise River, the critical flows are the 30-day and 7-day average flows for each season. The seasonal load capacities were determined by multiplying the minimum 30- and 7-day average flows by the 50 (for 60 days) and 80 (for 14 days) mg/L target concentrations.

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Bacteria The load capacity for bacteria was based on existing water quality standard criteria for primary and secondary contact recreation, using fecal coliform as a surrogate indicator. Two stream segments of the Lower Boise River were listed as impaired by bacteria, Star to Notus, and Notus to the Snake River. The compliance locations for the TMDL (DEQ, 1999) are the Boise River at the Glenwood Bridge (13206000), the Boise River at the USGS Middleton gage (13210050), and the Boise River at the USGS Parma gage (13213000).

Load Allocations Although Lower Boise River stream segments were listed as impaired by flow alteration due to the many diversions and dams, a TMDL was not written for this impairment because it is not a pollutant for which a load can be allocated and water rights are not regulated by DEQ. LAs for sediment in the Boise River were assigned to the four listed stream segments of the mainstem on the 1998 303(d) list: from Lucky Peak Dam to the Barber diversion, Barber diversion to Star, Star to Notus and Notus to the confluence with the Snake River. LAs for bacteria were assigned to two listed stream segments as described in the previous paragraph. The rationale for each pollutant and allocation are thoroughly described in the TMDL and summarized in the following tables and paragraphs.

Sediment Sediment allocations for the Lower Boise River were designated in the 1999 TMDL and Kuna was added in the 2008 addendum as summarized in Table 4 and Table 5.

Table 4. Subbasin point source wasteload allocations for total suspended sediment (TSS) (DEQ, 1999; 2008). Source Lander Street West Boise Meridian Nampa Caldwell Star Middleton Notus Armour Kuna

Design Flow, MGD* 15 24 2.82 11.76 8.48 0.33 1.83 0.056 0.475 3.5

Monthly Average Permit Limit TSS* mg/L

TSS Average Wasteload Allocations lbs/day 3400 lbs/day monthly1, 5000 lbs/day weekly1 3500 lbs/day monthly2, 3750 lbs/day weekly2 6200 lbs/day monthly, 9300 lbs/day weekly 710 lbs/day monthly, 1065 lbs/day weekly 3000 lbs/day monthly, 4500 lbs/day weekly 2125 lbs/day monthly, 3183 lbs/day weekly 193 lbs/day monthly, 290 lbs/day weekly 1070 lbs/day monthly, 1605 lbs/day weekly 33 lbs/day monthly, 50 lbs/day weekly 125 lbs/day monthly, 154 lbs/day weekly 876 lbs/day monthly, 1314 lbs/day weekly

30 30 30 30 30 70 70 70 None 30

8.4 tons/day3 monthly average

Total * MGD – million gallons per day 1 April 1 – September 30 2 October 1 – March 31 3 Using April – September limits Boise City, monthly limits all facilities

The sediment LAs to nonpoint sources were based on an equal percent reduction for all tributaries and drains. A 37% reduction was computed from the 1995 low flow year.

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table 5. Subbasin TMDL (DEQ, 1999) tributary and nonpoint source load allocations for total suspended sediment (TSS). Source

TSS Allocation, Tons per Day

Eagle Drain Thurman Drain Riparian Load #1

1.61 0.34 2.45

Allocations to Middleton

4.40

Fifteenmile Creek Star Feeder Long Feeder Watts Creek Mill Slough Willow Creek Mason Slough Mason Creek East and West Hartley Gulch Indian Creek Conway Gulch Dixie Drain Riparian Load #2, #3

18.02 1.73 0.35 0.28 7.08 2.28 1.20 21.48 5.31 5.74 7.14 25.91 4.90

Allocations to Parma Watershed Total

101.42 105.82

Bacteria The TMDL used fecal coliform allocations to comply with WQS in effect in 1999. The bacteria criteria were modified in 2007 to an E. coli standard. The criteria for E. coli are not to exceed 126 colony-forming units per 100 milliliters (cfu/100 mL) based on the geometric mean (geomean) of five samples collected three to seven days apart within a 30-day period. As described in the TMDL and Addendum, the geomean value applies year-round at variable flows. The fecal coliform target was revised from the Lower Boise River TMDL (DEQ, 1999) in an addendum approved by EPA in June 2008. The 1999 and 2008 revised allocations are summarized in Table 6 and Table 7. Critical low-flow bacteria loads for the two listed stream segments of the Lower Boise River were developed using information from USGS gage sites at Glenwood Bridge (13206000), Middleton (13210050) and Parma (13213000). Each listed tributary in the subbasin was assigned a load allocation at its confluence with the mainstem Lower Boise River.

Table 6. Lower Boise River TMDL (DEQ, 1999) and Addendum (DEQ, 2008) bacteria load allocations for mainstem and point source locations. Source

Lander Street WWTP Glenwood Bridge West Boise

Design Primary Recreation Secondary Recreation Flow Target, FC* / E. coli Target, FC / E. coli (cfs*) cfu/100 mL cfu/100 mL 15

110

50 / 126 geomean

24

50 / 126 geomean

Point Source Wasteload Allocations May 1 - Sept. 30

Point Source Wasteload Allocations Oct. 1 - Apr. 30

Monthly 50 Weekly 100 Daily 500

Monthly 100 Weekly 200 Daily 800

Monthly 50 Weekly 100 Daily 500

Monthly 100 Weekly 200 Daily 800

200 / 126 geomean

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

Source

Design Primary Recreation Secondary Recreation Flow Target, FC* / E. coli Target, FC / E. coli (cfs*) cfu/100 mL cfu/100 mL 2.82

50 / 126 geomean

2.82

50 / 126 geomean

11.76

50 / 126 geomean

Caldwell

8.48

50 / 126 geomean

Star

0.33

50 / 126 geomean

Meridian to Fivemile Creek Meridian to Boise River Nampa

Middleton

151

Wilder

50 / 126 geomean

200 / 126 geomean

126 geomean

Notus

0.056

50 / 126 geomean

Armour (XL Four Star Beef) Kuna

0.475

50/126 geomean

3.5

50 / 126 geomean

Parma

50 / 126 geomean

February 2009

Point Source Wasteload Allocations May 1 - Sept. 30

Monthly 100 Weekly 200 Daily 800 Monthly 50 Weekly 100 Daily 500 Monthly 200 Weekly 200 Daily 800 Monthly 50 Weekly 100 Daily 500 Monthly 50 Weekly 100 Daily 500 Monthly 50 Weekly 100 Daily 500 Monthly 100 Weekly 200 Daily 500 Monthly 50 Weekly 100 Daily 500 Monthly 50 Daily 400

Point Source Wasteload Allocations Oct. 1 - Apr. 30

Monthly 100 Weekly 200 Daily 800 Monthly 100 Weekly 200 Daily 800 Monthly 100 Weekly 200 Daily 800 Monthly 100 Weekly 200 Daily 800 Monthly 100 Weekly 200 Daily 800 Monthly 100 Weekly 200 Daily 800 Monthly 100 Weekly 200 Daily 800 Monthly 100 Weekly 200 Daily 800 Monthly 200 Daily 400

200 / 126 geomean

* cfs – cubic feet per second; FC – fecal coliform; cfu – colony-forming units

Table 7. Lower Boise River TMDL (DEQ, 1999) and Addendum (DEQ, 2008) bacteria load allocations for nonpoint source locations (tributaries and drains). Source

Eagle Drain Thurman Drain Fifteenmile Creek Star Feeder Long Feeder Watts Creek Mill Slough Willow Creek Mason Slough Mason Creek East and West Hartley Gulch Indian Creek Conway Gulch Dixie Drain

Primary Recreation Target, FC / E. coli in cfu/100 mL

Secondary Recreation Target, FC / E. coli in cfu/100 mL

FC 50 E. coli geomean 126

FC 200 E. coli geomean 126

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Margin of Safety Sediment The TMDL (DEQ, 1999) and technical appendices detail the methods used to determine the sediment criteria protective of the most sensitive beneficial use, salmonid spawning (SS). It was determined that 80 mg/L TSS in a 14-day acute exposure would be protective of adult fish. The target of 50 mg/L TSS in a 60-day chronic exposure would be protective of the eggs and larval stages of fish. The salmonids present in the Boise River are rainbow/redband trout, brown trout and mountain whitefish. In order to arrive at conservative values for target loads, the 30-day low-flow was selected as the critical flow. This flow is lower than the 60-day minimum flow associated with chronic criteria. Sediment LAs in the TMDL are less than the total capacity, which left a margin of safety relative to the target concentration and the critical flow load capacity. Therefore, the loads incorporate a variety of implicit and explicit safety elements that conservatively allocate suspended sediment loads to the Lower Boise River subbasin. Using the critical flow condition (low-flow), the margin of safety at Parma is 41% of the river capacity, or 37 tons per day.

Bacteria The beneficial use affected by bacteria pollution in the Lower Boise River subbasin is primary contact recreation (PCR) from May 1 to September 30 and secondary contact recreation (SCR) for the rest of the year. The TMDL and technical appendices provide details of methods and rationale for developing a bacteria TMDL for the Lower Boise River from Star to Notus and Notus to the confluence with the Snake River. Because contact recreation is presumed to occur in the subbasin all times of year under all flow conditions, no specific flow condition is recognized as critical for bacteria. The point source WLAs for bacteria were equal to existing permit limits and the tributary loads were estimated using the lowest flow year on record for the Lower Boise River subbasin (1992). These conditions created implicit conservative estimated load capacities that were augmented by calculating geometric means (geomeans) using widely-spaced sample results, as detailed in appendix I of the TMDL, and presuming no dilution available to the tributaries. The TMDL recommended that if E. coli became the standard for bacteria criteria, reported results of E. coli samples could be used to demonstrate compliance with criteria. The reductions needed to achieve target loads were large and conservative, with most tributaries requiring more than 90% reduction in load. The reduction was recommended as an indicator of the level of reduction that may be necessary to meet numeric WQS criteria rather than a goal.

Seasonal Variation In order to protect the most sensitive beneficial use from sediment pollution, critical flow and load capacities were calculated for the high-flow season (first flush of sediment) and the irrigation season. To make the load capacity more sensitive to the seasonal characteristics of the watershed, load capacities were calculated for low, median and high-flow years at Middleton and Parma. . For bacteria, the seasonal variation is supported in the WQS by the difference between primary and secondary contact recreation criteria, with primary criteria applicable from May 1 to Sept. 30, and secondary criteria applicable the rest of the year. Using the geomean criteria, a single sample result above numeric criteria does not necessarily constitute exceedance of criteria.

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Reserve for Growth A TMDL implementation plan was developed in 2003 and an addendum to the TMDL was developed and approved by EPA in 2008. The addendum defines the method for allocating reserved loads in the future and provides sediment and bacteria wasteload allocations (WLAs) to the City of Kuna. A reserve of total suspended sediment is included for each point source for the sum of the expected suspended sediment loads that occur in a twenty-year period. This reserve accounts for the difference between current design flows and the flows expected after 20 years of population growth in the Treasure Valley. The 20-year timeframe is consistent with other community planning documents being developed by communities in the subbasin. The most recent calculated reserve for sediment is 3.098 tons/day (DEQ, 2008). Because there is no reserve capacity for bacteria in the Lower Boise River subbasin, permit limits are based on the gemoean water quality standard for E. coli of 126 cfu per 100/mL.

Tributary Subbasin Assessments After the SBA and TMDLs for the Lower Boise River were written, separate SBAs addressed pollutants including nutrients, bacteria and sediment in the Lower Boise River and for the major tributaries: Blacks, Fivemile and Tenmile, Indian, Mason and Sand Hollow Creeks (DEQ, 2001). These documents are available from the DEQ website at

http://www.deq.state.id.us/water/data_reports/surface_water/tmdls/sba_tmdl_master_list. cfm. The results of the 2001 Lower Boise River SBA of tributaries for nutrients and sediment are summarized in Table 8 and the 2002 303 (d) list is provided in Table 9. The draft 2008 Integrated Report was open for public comment from January 2008 through February 20, 2008 and lists 26 AUs in the Lower Boise River Subbasin in Section 5: Impaired Waters, Lakes and Rivers “(303(d) list)”.

Table 8. Summary of Lower Boise River and tributaries subbasin nutrient and sediment assessment (2001). Stream Segment

AU

Lower Boise River 011b_06; Star to Notus and 001_06 Notus to Snake River Blacks Creek 009

Fivemile Creek

010

Indian Creek 003 headwaters to New York Canal

Pollutants Addressed in the SBA Nutrients

Proposed Listing Action Remove from the 303(d) list

Nutrients, Sediment, Dissolved Oxygen, Bacteria Nutrients, Sediment, Dissolved Oxygen, Bacteria Nutrients, Sediment

Other Action

None

Remove nutrients, None sediment, dissolved oxygen from the 303(d) list Remove nutrients, Schedule bacteria TMDL sediment, dissolved oxygen from the 303(d) list; add bacteria Remove nutrients and None sediment from the 303(d) list

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

Stream Segment

AU

Indian Creek New 003; 002 York Canal to mouth

Mason Creek

006

Sand Hollow Creek

017

Pollutants Addressed in the SBA Nutrients, Dissolved Oxygen, Oil/Grease, Bacteria

Nutrients, Sediment, Dissolved Oxygen, Bacteria Nutrients, Sediment, Dissolved Oxygen, Bacteria

February 2009

Proposed Listing Action

Other Action

Remove nutrients and oil/grease from the 303(d) list. Do not remove sediment or dissolved oxygen. Add bacteria to the 303(d) list.

Sediment: implement the Boise River sediment TMDL and monitor sediment conditions in Indian Creek. DO: monitor DO levels to ensure that they remain above 6.0 mg/L. Schedule bacteria TMDL. Schedule bacteria TMDL

Remove nutrients, sediment and dissolved oxygen from the 303(d) list; add bacteria Remove nutrients and DO, but not sediment from the 303(d) list. Add bacteria.

Sediment: Sand Hollow Creek SAWQP. Monitor sediment conditions in Sand Hollow Creek.

Table 9. Lower Boise River subbasin 2002 303(d) list. AU 001_02 001_06 002_04

Stream Segment Description Boise River- Indian Creek to mouth Boise River- Indian Creek to mouth Indian Creek - 4th order

003_02

Indian Creek - 1st and 2nd order

003_03

Indian Creek - 3rd order

003_04 004_06

Indian Creek - 4th order Lake Lowell Boise River - river mile 50 (T04N, R02W, Sec. 32) to Indian Creek Mason Creek - entire watershed Tenmile Creek - 3rd order below Blacks Creek Reservoir Blacks Creek - 1st and 2nd order Blacks Creek - 3rd order Fivemile Creek - 1st and 2nd order Fivemile Creek - 3rd order Boise River - Diversion Dam to river mile 50 (Glenwood

005_06 006_02 008_03 009_02 009_03 010_02 010_03 011a_06 011b_02 012_02 012_03 015_02 015_03 016_03 017_03 017_06

Bridge)

Boise River-Lucky Peak Dam to Diversion Dam Stewart Gulch, Cottonwood and Crane Creeks - 1st & 2nd order Cottonwood Creek - 3rd order: Fivemile Creek to Boise River Willow Creek - source to mouth Willow Creek - source to mouth Langley/Graveyard Gulch complex Sand Hollow Creek - I-84 to Boise River Sand Hollow Creek - source to mouth

17

Pollutant Temperature Nutrients, Temperature Fecal Coliform, Temperature Fecal Coliform, Nutrients, Sediment Fecal Coliform, Sediment, Temperature Nutrients, DO, Sediment, Temperature Cause Unknown Temperature Nutrients, DO, Sediment Nutrients, Pathogens, Sediment Unknown Unknown DO, Pathogens, Sediment DO, Nutrients, Sediment Temperature Flow Alteration Unknown Unknown Unknown, Temperature Unknown, Temperature Nutrients, DO, Sediment Fecal Coliform, DO, Sediment Nutrients, DO, Sediment

Lower Boise River 5-year Subbasin Assessment and TMDL Review

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February 2009

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Section 3: Beneficial Use Status Idaho WQS were revised in 2007 and are defined in IDAPA 58.01.02, but have not yet been approved by EPA. The standards designate beneficial uses for Idaho surface water bodies, by HUC and subbasin (or specific water body), and set water quality criteria for the waters of the State. Idaho WQS require that surface waters of the State be protected for the most sensitive beneficial uses (IDAPA 58.01.02), which may be interpreted as existing uses, designated uses, or presumed uses. The WBAG II (Grafe et al., 2002) gives a detailed description of beneficial use identification for use assessment purposes. Existing uses under the CWA are “those uses actually attained in the water body on or after November 28, 1975, whether or not they are included in the water quality standards. Designated uses are specifically listed for water bodies in Idaho in tables in the Idaho WQS (see IDAPA 58.01.02.003.27 and .02.109-.02.160 in addition to citations for existing uses). Undesignated uses are protected for uses presumed by the state to exist. Absent information on existing uses, DEQ presumes that most waters in the state will support cold-water aquatic life and either primary or secondary contact recreation (IDAPA 58.01.02.101.01). To protect presumed uses, DEQ will apply numeric cold-water criteria (COLD) and primary or secondary contact recreation criteria (PCR/SCR) to undesignated waters. Criteria that apply to water bodies in the Lower Boise River subbasin are summarized in Figure 5. Waters designated as special resource waters (SRW) have narrative criteria that limits existing point source discharge to current design capacity and prohibits additional permitted point source discharges. Domestic water supply (DWS) designated uses must comply with the numeric criteria for toxic substances as referenced in IDAPA 58.01.02.210. AUs 011a and 011b are the only AUs in the Lower Boise River subbasin designated as SRW and DWS. The recent WQS revisions (2007) include a designation and criteria for modified communities (MOD) which have not yet been approved by EPA. Because creating or changing use designations and criteria require Idaho to engage in the rule-making process, designations in the current standards will remain until the required process is completed before making other changes, even if that change is to reinstate the use that was designated in previous WQS. While the MOD beneficial use criteria have not been approved by EPA, Idaho has not yet initiated the rule-making procedures required to reinstate the previous use designation. When that process is complete, all available data will be compared to the appropriate standard criteria to determine use attainment status.

Beneficial Uses Table 10 summarizes revisions made to Idaho WQS (2007) for each of the AUs in the Lower Boise River subbasin that are listed in the draft 2008 Integrated Report.

19

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table 10. Summary of Lower Boise River subbasin impairments from the draft 2008 Integrated Report and beneficial uses from Idaho water quality standards (2007). Assessment Unit 001_02

Unnamed 1st and 2nd order tributaries to Boise River between Indian Creek and the mouth. Boise River 6th order from Indian Creek to the mouth, and tributaries to the 6th order. Indian Creek 4th order from Phyllis Canal to mouth.

Temperature

Designated Use (*not approved by EPA) Undesignated

Temperature

COLD, PCR

Temperature, Bacteria

COLD, SCR

003_02

North Indian Creek, 1st and 2nd order.

Undesignated

003_03

Indian Creek 3rd order, upstream of Sand Creek

Sediment, Bacteria, Nutrients Sediment, Temperature, Nutrients

003a_04

Indian Creek 4th order from Sand Creek to Phyllis Canal.

Sediment, Temperature, DO, Unknown

MOD*, SCR

005_02

First and second order unnamed streams or tributaries to the Boise River from 4 miles upstream of Eagle to Mason Creek.

Unassessed

Undesignated

005_06

Boise River 6th order, from 4 miles upstream of Eagle to Indian Creek and unnamed tributaries to 6th order.

Temperature

COLD, SS, PCR

006_02

Mason Creek source to mouth.

Sediment, Unknown, Nutrients, DO

MOD*, SCR

007_02

First and second order Fifteenmile Creek, Miller canal to mouth. Third order Fifteenmile Creek, Miller canal to mouth.

Unassessed

Undesignated

Unassessed

MOD*, SC, SCR

08_02

1st and 2nd order tributaries to Tenmile Creek.

Unassessed

Undesignated

008_03

Tenmile Creek

MOD*, SCR

009_02

Blacks Creek 1st and 2nd order.

Bacteria, Unknown, Nutrients Habitat Alteration

Undesignated

009_03

Blacks Creek 3rd order.

Habitat Alteration

Undesignated

010_02

Fivemile Creek 1st and 2nd order.

Bacteria

Undesignated

010_03

Fivemile Creek 3rd order.

MOD*, SCR

011a_02

1st and 2nd order tributaries to Boise River from Barber Dam to Glenwood Bridge.

Habitat Alteration, Unknown, Nutrients, DO Unassessed

001_06

002_04

007_04

Stream

Pollutant

20

COLD, SCR

Undesignated

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit 011a_06

Stream

February 2009

Pollutant

Designated Use (*not approved by EPA) COLD, SS, PCR, DWS, SRW

Boise River from Barber Dam to Glenwood Bridge.

Temperature

011b_02

1st and 2nd order streams and tributaries near outfall of Lucky Peak Dam.

Unassessed

Undesignated

011b_06

Boise River between Lucky Peak outfall and Diversion Dam. Stewart Gulch, Cottonwood and Crane Creeks source to 3rd order. Stewart Gulch, Cottonwood and Crane Creeks, 3rd order to mouth.

Flow Alteration Habitat Alteration

COLD, PCR, DWS, SRW Undesignated

Habitat Alteration,

Undesignated

Unassessed

Undesignated

013_03

1st and 2nd order Dry Creek and tributaries. 3rd order Dry Creek and tributaries.

Unassessed

Undesignated

013_04 014_02

4th order Dry Creek. Big/Little Gulch Creek Complex.

Unassessed Unassessed

Undesignated Undesignated

015_02

Habitat Alteration, Temperature Habitat Alteration, Temperature

Undesignated

015_03

1st and 2nd order Dry Creek and tributaries. 3rd order Dry Creek and tributaries.

016_02 016_03

Big/Little Gulch Creek Complex. Big/Little Gulch Creek Complex.

Unassessed Sediment, DO, Unknown, Nutrients

Undesignated Undesignated

117_02

1st and 2nd order Sand Hollow Creek and tributaries. South Fork Willow Creek.

Unassessed

Undesignated

Sediment, Bacteria, DO, Unknown

MOD*, SCR

Sediment, Unknown, Nutrients, DO

MOD*, SCR

012_02 012_03 013_02

017_03 017_06

Willow Creek, North Fork Willow Creek, and unnamed tributaries.

Undesignated

COLD – cold water communities, SC – seasonal cold water communities, WARM – warm water communities, SS – salmonid spawning, PCR – primary contact recreation, SCR – secondary contact recreation, AWS – agricultural water supply, SRW – special resource water, DWS – domestic water supply, MOD* – modified communities (not approved by EPA)

Beneficial uses are protected by a set of criteria, which include narrative criteria for pollutants such as sediment and nutrients and numeric criteria for pollutants such as bacteria, dissolved oxygen, pH, ammonia, temperature and turbidity (IDAPA 58.01.02.250). Figure 5 provides an outline of the stream assessment process for determining support status of the beneficial uses of cold water aquatic life, salmonid spawning, and contact recreation. Table 11 includes the numeric criteria used for reviewing the beneficial use status pertinent to the waters of the Lower Boise River subbasin.

21

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure 5. Determination Steps and Criteria for Determining Support Status of Beneficial Uses in Wadeable Streams: Water Body Assessment Guidance, Second Edition (Grafe et al., 2002).

22

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table 11. Idaho Water Quality Standards, adopted in 2007 (not yet approved by EPA), applicable to the Lower Boise River subbasin. Designated and Existing Beneficial Uses Water Quality Parameter

Primary Contact Recreation

Bacteria, pH, and Dissolved Oxygen

Less than 126 E. a coli/100 ml as a geometric mean of five samples over 30 days; no sample greater than 406 E. coli organisms/100 ml

Temperature

d

Secondary Contact Recreation

Cold Water Aquatic Life

Water Quality Standards: IDAPA 58.01.02.250 pH between 6.5 and 9.0 Less than 126 E. coli/100 ml as a b c DO exceeds 6.0 mg/L geometric mean of five samples over 30 days; no sample greater than 576 E. coli/100 ml

22 °C or less daily maximum; 19 C or less daily average

MOD

Seasonal Cold Water: Between summer solstice and autumn equinox: 26 °C or less daily maximum; 23 °C or less daily average

Turbidity

Turbidity shall not exceed background by more than e 50 NTU instantaneously or more than 25 NTU for more than 10 consecutive days. Ammonia not to exceed calculated concentration based on pH.

Ammonia

Salmonid Spawning (During Spawning and Incubation Periods for Inhabiting Species) pH between 6.5 and 9.5 Water Column DO: DO exceeds 6.0 mg/L in water column or 90% saturation, whichever is greater; Intergravel DO: DO exceeds 5.0 mg/L for a one day minimum and exceeds 6.0 mg/L for a seven day average 13 °C or less daily maximum; 9 °C or less daily average Bull trout: not to exceed 13 °C maximum weekly maximum temperature over warmest 7-day period, June – August; not to exceed 9 °C daily average in September and October

a

Escherichia coli colony forming units per 100 milliliters dissolved oxygen c milligrams per liter d Temperature Exemption - Exceeding the temperature criteria will not be considered a water quality standard violation when the air temperature exceeds the ninetieth percentile of the seven-day average daily maximum air temperature calculated in yearly series over the historic record measured at the nearest weather reporting station. e Nephelometric turbidity units b

Current Water Quality Data Sources A request for data collected during the past five years was made by DEQ to the WAG in March and May of 2008. A compilation of the data received in response to those requests is included in the appendices. Because data collected from any site within the AU may be extrapolated to infer conditions throughout the AU, Tier I data as defined in the WBAG II (Grafe, et al., 2002) is used to make recommendations about future listing status. Several agencies and point source permit holders collect water quality data from many different locations throughout the subbasin. Table 12 summarizes data collection by agencies involved in regulatory or land management activities, including data collected and reviewed for this report, and Appendix C includes data from those sources. The

23

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

WAG contracted with the USGS to collect instantaneous water quality, aquatic biota, and continuous discharge (flow volume) data from six of the 18 control monitoring locations, and four other subbasin locations, to determine compliance with the TMDL in the past five years. Table 12. Summary of Lower Boise River subbasin data sources used in five-year review, determination of beneficial use attainment and pollutant type. Assessment Stream Collection Data Collected Unit (draft 2008 Segment Description Agency Integrated Report) 001_02 Unnamed 1st and 2nd DEQ Satellite photo image review. order tributaries to the Boise River between Indian Creek and the mouth. 1 1 001_06 Boise River 6th order DEQ, BURP data, satellite photo image 2 USGS, from Indian Creek to review. 2 Discharge, nutrients, 3 ISDA, bacteria, sediment, field the mouth, and 4 CB, parameters, biology. 3 Nutrients, tributaries to the 6th 5 BOR bacteria, sediment, field order. parameters. 4Temperature. 5 Bacteria, sediment.

002_04

Indian Creek 4th order from Phyllis Canal to mouth.

1

003_02

North Indian Creek, 1st and 2nd order. Indian Creek 3rd order, upstream of Sand Creek. Indian Creek 4th order from Sand Creek to Phyllis Canal.

DEQ

003_03

003a_04

005_02

005_06

1st and 2d order unnamed streams or tributaries to the Boise River from Glenwood Bridge to Mason Creek. Boise River 6th order, from Glenwood Bridge to Mason Creek and tributaries to 6th order.

DEQ, USGS, 3 ISDA, 6 CN 2

1

Satellite photo image review. Discharge, nutrients, bacteria, sediment, field parameters. 3 Nutrients, bacteria, sediment, field parameters. 6 Nutrients, bacteria, sediment, field parameters. Satellite photo image review 2

2008

1

1995, 2008; 1939-40, 1950-1973, 1981-83, 1994-2001, 2005; 3199899, 2008, 4 2002-2007; 5 2006 1 2008; 2 1981-2007; 3 1998-99, 2008, 620032008 2

2008 1

DEQ

BURP data, satellite photo image review. Nutrients, bacteria, sediment, field parameters. 1BURP data, satellite photo image review. 2 Discharge, nutrients, bacteria, sediment, field parameters. Satellite photo image review.

1

1

1

DEQ 1

DEQ,

DEQ, USGS, 3 ISDA, 4 CB, 5 BOR 2

24

1

Year

BURP data, satellite photo image review. Nutrients, bacteria, sediment, field parameters. 2 Discharge, nutrients, bacteria, sediment, field parameters, biology. 3Nutrients, bacteria, sediment, field parameters. 4 Temperature. 5Bacteria, sediment.

1996-7, 2004, 2008

1

1995, 1997, 2003-04; 2008; 2008

1995, 2008; 1971-2003; 3 2001-2008; 4 1999-2008; 5 2006 2

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Assessment Stream Collection Data Collected Unit (draft 2008 Segment Description Agency Integrated Report) 1 1 006_02 Mason Creek source DEQ, BURP data. 2Nutrients, bacteria, 2 USGS, to mouth. sediment, field parameters. 3 3 IDA Nutrients, bacteria, sediment, field parameters. 007_02 Fifteenmile Creek, 1st DEQ Satellite photo image review. and 2nd order and tributaries 1 1 007_04 Fifteenmile Creek, 3rd DEQ, Satellite photo image review. 2 2 USGS, Discharge, temperature, nutrients, order and tributaries to 3 ISDA bacteria, sediment, field mouth parameters. 3Nutrients, bacteria, sediment, field parameters. 008_02 1st and 2nd order Satellite photo image review. DEQ, tributaries to Tenmile Creek. 1 1 008_03 Tenmile Creek DEQ, BURP data. 2Nutrients, bacteria, 2 USGS, sediment, field parameters. 3 3 ISDA Nutrients, bacteria, sediment, field parameters. DEQ BURP data, satellite photo image 009_02 Blacks Creek 1st and review. 2nd order. 009_03 Blacks Creek 3rd DEQ, BURP data, satellite photo image order. review. 010_02 Fivemile Creek 1st and DEQ, BURP data, satellite photo image 2nd order review. 1 1 010_03 Fivemile Creek 3rd DEQ, BURP data, satellite photo image 2 USGS, order. review. 2Nutrients, bacteria, 3 ISDA sediment, field parameters. 3 Nutrients, bacteria, sediment, field parameters. 011a_02 1st and 2nd order Satellite photo image review. DEQ tributaries to Boise River from Barber Dam to Glenwood Bridge. 1 1 011a_06 Boise River from DEQ, Satellite photo image review. 2 2 USGS, Discharge, temperature, nutrients, Barber Dam to 4 CB, bacteria, sediment, field Glenwood Bridge. 5 BOR parameters, biology. 4 Temperature. 5Sediment, bacteria, field parameters. 011b_02 1st and 2nd order Satellite photo image review. DEQ streams and tributaries near outfall of Lucky Peak Dam. 1 1 011b_06 Boise River between DEQ, Satellite photo image review. 2 2 USGS, Discharge, biology. 4Continuous Lucky Peak outfall and 5 BOR temperature. 5Sediment. Diversion Dam.

25

Year

1

2003; 1994-2001, 2005; 319981999, 2008 2008 2

1

2008, 2005, 319981999

2

2008 1

1996-7; 1994-2001, 2005; 319981999 1996, 1998, 2008 1998, 2008 2

1998, 2008 1

1996, 2003, 2005, 2008; 2 2000-01, 2005; 319981999 2008

1

2008; 1981, 19952004, 2005; 4 2002-2007; 5 1998, 2006 2

2008

1

2008; 1986-1994, 2002-4, 2006; 420032007, 52002 2

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Assessment Stream Collection Data Collected Unit (draft 2008 Segment Description Agency Integrated Report) 012_02 First and second order DEQ BURP data, satellite photo image Stewart Gulch, review. Cottonwood and Crane Creeks. 1 1 012_03 Stewart Gulch, DEQ, BURP data, satellite photo image 2 Cottonwood and Crane USGS review. 2Discharge. Creeks from 3rd order to the mouth. 1 013_02 Unnamed tributaries to 1DEQ, Satellite photo image review. 3 3 ISDA Nutrients, bacteria, sediment, field Dry Creek. parameters. 013_03 3rd order Dry Creek DEQ Satellite photo image review. and tributaries. 013_04 4th order Dry Creek DEQ Satellite photo image review. and tributaries. 014_02 Big and Little Gulch DEQ Satellite photo image review. complex 015_02 1st and 2nd order DEQ BURP data, satellite photo image Willow, North Fork review. Willow, South Fork Willow Creeks and tributaries 1 1 015_03 3rd order Willow DEQ, BURP data, satellite photo image 3 ISDA Creek, North Fork review. 3Nutrients, bacteria, sediment, field parameters. Willow Creek, and tributaries. 016_02 Langley/Graveyard DEQ Satellite photo image review. Gulch complex, unnamed streams. 1 1 016_03 Langley/Graveyard DEQ BURP data, satellite photo image Gulch complex, review, nutrients, sediment, unnamed streams. bacteria, field parameters. 017_02 Sand Hollow Creek DEQ Satellite photo image review. (Payette River system) D-line, Farmers, Sebree, and Notus Canals and unnamed streams 1 017_03 Sand Hollow Creek 3rd 1DEQ BURP data, satellite photo image order and tributaries. review, nutrients, sediment, bacteria, field parameters. 1 1 017_06 Sand Hollow Creek, DEQ, Satellite photo image review. 3 3 ISDA Nutrients, bacteria, sediment, field 6th order and parameters. tributaries.

Year

1996, 2008

1

1996, 2008; 2002-2008

2

1

2008; 32008

1

2008

1

2008

1

2008

1

1996, 20045, 2008

1

1996, 2008; 2008

3

2008 1

1996, 2008

2008

1

1996, 2006, 2008

1

1996, 2008; 1998-9, 2008

3

1 Department of Environmental Quality (DEQ), 2 United States Geological Survey (USGS), 3 Idaho State Department of Agriculture (ISDA), 4 City of Boise (CB), 5 Bureau of Reclamation (BOR), 6 City of Nampa (CN).

26

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Changes to Subbasin Characteristics Previous studies predicted continued population growth in the subbasin (USACE, 1995), which has effected transitions in land use from agricultural to urban/suburban in all watersheds of the subbasin. Ada County has experienced more land use conversion than other counties, but all counties have more acres of urban/suburban land use now than in 2001. A Use Attainability Analysis (UAA) of tributaries and drains in the subbasin was conducted in 2002 and requests were submitted to EPA for approval to modify the designated use of some tributaries and drains in the subbasin. EPA approved the revision of recreation use designations for Indian, Mason, Sand Hollow, Fivemile, Tenmile and Fifteenmile Creeks from primary to secondary contact recreation. Because the WAG developed the TMDL and implementation plan to comply with geomean bacteria criteria, the revision from PCR to SCR use designation did not change the TMDL target and LAs, which remain at 126 cfu/100mL of E. coli.

Pollution Source Review This report includes a review of identified or observed sources of impairment to surface water in the subbasin, including permitted point sources, nonpoint sources, natural events and documented or otherwise known accidental releases. The EPA published a new Multi Sector General Permit (2008 MSGP) on September 29, 2008 to replace the 2000 MSGP. This permit covers industrial facilities where EPA has NPDES authority, such as the Lower Boise River subbasin. The 2008MSGP applies to all new and existing facilities and requires that stormwater be controlled in accordance to the permit. The permit can be accessed at: http://cfpub.epa.gov/npdes/stormwater/msgp.cfm. An online database scheduled to be active after February 12, 2009 will allow the public to access information on the MSGP entities under EPA’s authority. This database can be accessed at: http://cfpub.epa.gov/npdes/stormwater/enoi.cfm. In response to an anticipated change in standards for recreational uses, the WAG sponsored a study to identify sources of bacteria pollution in the subbasin by identifying fecal coliform DNA. The DNA study resulted in identifying approximately 70% of the sources of bacteria in the subbasin (e.g. human, cattle, horse, bird, dog and cat) and determining the proportion of controllable sources (those that can be controlled by humans) (LBRWQP, 2003). Point Sources Permitted point sources in Ada and Canyon counties, retrieved from the EPA website and summarized in Table 13 and Figure 6, are easy to identify and are required to meet all permit conditions. Details regarding the permitted facilities can be queried from the EPA web site: http://www.epa.gov/enviro/index.html. Recent federal requirements for cities and construction sites to develop and implement stormwater control systems, and to apply for NPDES permits which require implementation of BMPs for stormwater control on construction sites, have facilitated reductions in sediment loads from those sources in the past five years. EPA has recently published a draft guidance document, TMDLs to Stormwater Permits Handbook: Draft (2008) to assist in the development of TMDLs

27

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

with identified stormwater sources for certain pollutants. This guidance draft can be accessed from http://www.epa.gov/owow/tmdl/pdf/tmdl-sw_permits11172008.pdf. Data collected from five locations in the Boise region for the Boise City Municipal Storm Water NPDES Permit is published annually by the Ada County Highway District (ACHD). The sample locations are in AUs 005_02, 010_02 and 011a_06, and analytical samples are collected from stormwater effluent, not the stream channel. Although there are numerous construction NPDES permits in Ada and Canyon counties, they are not included in Table 13 because they are required to keep stormwater on site and are temporary in nature. Table 13. NPDES-permitted point sources in the Lower Boise River subbasin, as of March 2008. Sewage Treatment Facilities Longitude 116.42315 116.70269 116.687778 116.4014 116.81469 116.95958 116.49222 116.58197 116.638 116.815443 116.909467 116.52388 116.70888 Longitude 116.33127 116.24419 116.22127

116.2619 116.4 116.4975

Canyon County Facility Receiving Water MS41 City of Caldwell* Indian and Mason Creeks City of Caldwell WWTP2 Boise River and Indian Creek Darigold, Caldwell Boise River Petroleum tanks Indian Creek City of Notus Boise River, through Conway gulch City of Parma Sand Hollow Creek Sorrento Lactalis cheese plantBoise River, through Rachel and 43.605833 Nampa Purdam Drain 43.598111 City of Nampa WWTP Indian Creek 43.696694 City of Middleton WWTP Boise River 43.669816 City of Greenleaf WWTP Boise River 43.677182 City of Wilder Undisclosed 43.576944 Swift and Company Beef Indian Creek 43.702777 Caldwell Housing Authority Sebree Canal Ada County Latitude Facility Receiving Water **City of Boise MS4 Boise River 43.67175 City of Boise WWTP Boise River 43.638888 City of Boise WWTP Boise River 43.614666 City of Boise GeothermalBoise River City of Kuna Indian Creek City of Eagle Boise River Avimor Community Boise River Garden City Boise River 43.382 City of Meridian WWTP Fivemile Creek and Boise River 43.591666 Roaring Springs Water Park Tenmile Creek 43.687111 City of Star WWTP Lawrence-Kennedy Canal Latitude 43.42095 43.677277 43.669444 43.4015 43.726888 43.786777

Permit # IDS028118* ID0021504 ID0024953 ID0027383 ID0021016 ID0021776 ID0028037 ID0022063 ID0021831 ID0028304 ID0020265 IDG10028 ID0025453 Permit # IDS027561 ID0023981 ID0020443 ID0025488 pending pending pending pending ID0020192 ID0027952 ID0023591

Animal Feeding Operations 116885409 116.7435 116.593316

43.844588 43.836142 43.422067

116.71306 116.87205 116.563033

43.69214 43.743333 43.380937

Canyon County Boise Valley Feeders Black Canyon Canal Choutchourrou's Dairy Undisclosed Chuck DeGroot Undisclosed Clarence Verdersteldt and Sons Indian Creek, through Mora Canal Diamond A Facility Undisclosed Ed Johnson Farms Undisclosed Melba Feedlot Undisclosed

28

IDG010079 IDG010162 IDG010160 IDG010099 IDU000059 IDU000062 IDU000170

Lower Boise River 5-year Subbasin Assessment and TMDL Review

116.934277 116.999185 -116.961587 117.012243 116.55297

43.88995 43.792139 43.793424 43.776033 42.533611

116.592799 116.729042 116.503537

43.42203 43.735505 43.55267

116.58805 116.893741

43.600555 43.81011

116.66194 116.539671 116.673127 116.712905

43.760833 43.329364 43.663715 43.504629

116.453811 116.473499 116.453636 116.439921

43.422881 43.479977 43.553375 43.422848

116.333814

43.424104

116.434254

43.721008

116.453604 Longitude 116.294403 116.433479 116.503708

43.474573 Latitude 43.530614 43.422789 43.48848

116.471092

43.422932

116.413774

43.467902

February 2009

VL Feedlot Undisclosed River Ranch Feedlot Undisclosed Fort Boise Cattle Company Undisclosed Van Vliet Dairy Farm South Boise Drain Idaho Fish and Game Wilson Springs M & M Feedlots Undisclosed McKenzie Feedlot Boise River, through Notus Canal Mooriah Dairy Boise River, through Mora Canal Niman Ranch Cattle Undisclosed Shulerlane Farms, Inc. Indian Creek Simplot Feedlot #3 Boise River Simplot Meat Packing Plant Indian Creek T & T Cattle Black Canyon Canal Nicholson Feed Lot Undisclosed Vandenberg Dairy Undisclosed Animal Feeding Operation Undisclosed Beef Cattle Feedlot Undisclosed Beranna Dairy Mora Canal Snake River Farms Snake River Stephens and Sons Undisclosed Norman Vermeer Undisclosed Ada County Carousel and Syringa Farms Waldvogel Canal Dairy Vanduzer lateral Van Grouw Dairy Mason Creek Double OO Dairy Undisclosed Dudley Ranch, Star Boise River Van Grouw Dairy Indian Creek Friesian Dairy Indian Creek Beacon Light Road Indian Creek Idaho Feedlot Undisclosed Morford Farms Undisclosed Facility Receiving Water Murgoittio Dairy New York Canal Silver Butte Holsteins, Inc. Undisclosed Bochsma Dairy Indian Creek and Boise River Stillwell 117 Ranch-Feedlots Undisclosed Sundance Dairy Waldvogel Canal Thornton Hog Farm Undisclosed Vandersteldt Dairy Undisclosed

1

MS4 – Municipal Multi-Sector Stormwater Facility 2 WWTP – wastewater treatment plant * Not Final **Includes ACHD, BSU, ITD, and Garden City as co-permitees

29

IDU000186 IDU000187 IDU000054 IDG010096 IDG130042 IDU000063 IDG010074 IDG010084 IDU000171 IDG010093 IDG010027 ID0026964 IDG010111 IDU000058 IDG010163 IDU000173 IDU000172 IDG010091 IDG010140 IDU000064 IDU000002 IDG010083 IDG010092 IDG010097 IDG010101 IDU000082 IDG010098 IDG010081 IDG010066 IDU000040 IDU000201 Permit # IDG010308 IDG010130 IDG010135 IDU000057 IDG010103 IDU000056 IDG010095

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure 6. Permitted point sources (wastewater treatment plants and confined animal feeding operations) in Lower Boise River subbasin as reported on the EPA Web site of NPDES permits in May 2008. Nonpoint Sources The TMDL identified nonpoint sources as primary contributors of sediment and bacteria pollution in the subbasin. Population growth in the subbasin since the TMDL was written has continued at a consistent rate, as predicted by the ACOE (1995), of 2 to 3% per year with the suburban regions experiencing the most significant change in land use from agricultural to urban. Because urban/suburban sources are regulated through permit instruments those sources contribute proportionately less sediment and bacteria pollution. In 2005, the Ada County Soil Conservation District estimated that 17 mi2 were converted from agricultural to urban land use in Ada County between 2001 and 2004 (Koberg, 2008). While the locations of agricultural diversions and drains can be indicated as specific points on the landscape, the CWA designates these as nonpoint sources due to the impact that widespread land use activities have on the water channeled through canal systems. Septic systems are discussed in the 2003 implementation plan for the Lower Boise River TMDL and are considered a small contributor of nonpoint source pollution in the subbasin.

30

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Natural Events Wildland fires, intense rainstorms, rain-on-snow events and similar infrequent and isolated, but high-impact, events occur in the subbasin and have been observed to have an acute negative effect on water quality. During the past five years, no events of significance occurred in the Lower Boise River subbasin. Flow and Habitat Alteration Initially, flow and habitat modifications in the subbasin were an indirect result of ore mining in the Upper Boise River subbasin. As mining camps expanded, the demand for food spurred the growth of agriculture in the Lower Boise River, leading to the development of reservoirs and canal systems as early as 1872 (ISHS, 1993). With the expansion of the territories of the United States, federal agencies were created and tasked with the responsibility for flood control and irrigation systems. The US Bureau of Reclamation (BOR), created in 1902 to develop and manage irrigation projects, is the responsible agency for managing water flow in the lower Boise River subbasin. All existing canals and irrigation systems were incorporated into the BORmanaged project. The agency negotiates contracts with water districts, water user associations and other federal agencies to operate the water systems. Dams and diversions currently remove an average of 5,200 cubic feet per second (cfs) from the mainstem river during the irrigation season for allocated uses as described in The Boise Project (US BOR, 1997). The portion of diverted water that is not consumed (59%) is returned to the mainstem at multiple locations between the city of Star and the mouth.

Summary of Analysis of Current Water Quality Data Since the TMDL was approved, DEQ has collected data, requested data from other agencies and organizations, and searched other agency databases, university publications and municipal or regional resource management plans for additional and recent water quality data. The results of that effort are compiled in this review and recommendations for future action and Integrated Reports is based on that data. The remainder of this section will address water quality data for criteria related to beneficial uses, pollutants, or impairments in the Lower Boise River subbasin that are addressed by an approved TMDL or used by Idaho as a standard for water quality. Pollutants of concern for this review are limited to constituents for which numeric criteria are established in Idaho WQS, and that have been identified as current or potential limiting factors for attainment of designated, existing, or presumed beneficial uses in the Lower Boise River subbasin. Those constituents are sediment, bacteria, temperature, DO, pH and ammonia. Sediment Sediment concentrations are used as a surrogate measure to determine attainment of SS and COLD beneficial uses. The TMDL established a dual maximum target suspended sediment concentration (SSC or TSS) for the Boise River of 80 mg/L for 14 days and 50 mg/L for 60 days from February through September. The target concentration applies to the mainstem river at any location and two locations (Middleton and Parma) were

31

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

identified as control monitoring locations. LAs were also established for 15 drains and tributaries using a mass balance-derived load reduction target of a 37% reduction from 1992 loads. For the purpose of determining TMDL attainment, data is compared to the concentration targets (50 mg/L or 80 mg/L) in the mainstem and data is compared to the current state standard (Table 11) and LAs for the tributaries. The TMDL allocated 3.62 tons/day as a reserve for growth. Subbasin assessments were completed for major tributaries in the Lower Boise River subbasin in 2001. Sediment was discussed in relation to salmonid spawning uses, but as none of the tributaries are designated for the beneficial use of salmonid spawning and the uses do not exist, cold-water aquatic life (COLD) beneficial uses are the most sensitive designated or presumed use for the tributaries. The surrogate WQS (Figure 11) for sediment that applies to COLD beneficial uses is turbidity. The relationship between suspended sediment and turbidity is explained in several reports (Downing, 2008; USGS, 2001; Lewis, 1996) and can be used along with other observations to determine use support. Ultimately, the determining factor for impairment due to sediment pollution is beneficial use attainment. Use attainment decisions are based on an evaluation of water chemistry data, BURP habitat assessments scores, and observation of conditions present within an AU. Current WQS use turbidity (Figure 11) as a surrogate measure for sediment, and to the extent that published research provides valid methods for correlating turbidity with SSC, it is possible to determine sediment impairment in some Lower Boise River tributaries. Instantaneous SSC or total suspended sediment (TSS) data has been collected at both mainstem control locations and 7 drain and tributary locations during the past five years. Reported data is compared to the TMDL targets in Figure 7, Figure 8 and Figure 9. At most mainstem river locations, except for Parma (AU 001_06), the TMDL sediment targets are met. Lower Boise River Suspended Sediment Concentrations (SSC), 2003-2008

Suspended Sediment Concentration (mg/L)

250 200 150 100 50 0 2/1

7 6 6 7 7 6 5 5 5 4 4 3 4 03 03 00 00 00 00 00 00 00 00 00 00 00 00 00 / 20 /1/ 20 9/ 2 /27/ 2 /26/ 2 /23/2 /21/ 2 /21/ 2 /18/ 2 /16/ 2 /16/ 2 /13/ 2 /11/ 2 /11/ 2 9/8/ 2 2 6 / 1 9 5 1 5 9 1 5 9 5 9 1

Date BR at Diversion

BR at Glenwood

BR at Star

BR near Parma

60 day maximum

14-day maximum

BR above Middleton

Figure 7. Graph of suspended sediment concentration (SSC) from USGS gage locations on the Boise River, 2003-2008.

32

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Lower Boise River Tributary Suspended Sediment Concentrations (SSC), 2005 Suspended Sediment Concentration (mg/L)

350 300 250 200 150 100 50 0 4/15/2005

5/15/2005

6/14/2005

7/14/2005

8/13/2005

Date Fivemile Ck

Tenmile Ck

Fifteenmile Ck

Willow Ck

Mason Ck

Indian Ck

60 day maximum

14-day maximum

Figure 8. Graph of suspended sediment concentration (SSC) from tributary locations near the confluence with the Boise River, 2005. Lower Boise River Drains Suspended Sediment Concentrations (SSC), 2005 Suspended Sediment Concentration (mg/L)

800 700 600 500 400 300 200 100 0 4/15/2005

5/15/2005

6/14/2005

7/14/2005

8/13/2005

Date Mill Slough

Conway Gulch

Dixie Drain

60 day maximum

14-day maximum

Figure 9. Graph of suspended sediment concentration (SSC) from drains near the confluence with the Boise River, 2005. Figure 8 and Figure 9 represent data collected from tributaries and drains near the confluence with the mainstem. Of the sampled tributaries to the Lower Boise River, Willow Creek (AU 015_03) is the only tributary that does not appear to exceed turbidity criteria or TMDL sediment targets. Of the three drains sampled in 2005, only Mill Slough (AU 005_06) appears to be within turbidity criteria or TMDL targets. It is not possible to determine sediment trends in the basin, given the limited data for this constituent. However, based on a review of the available data, AUs 002_04 (Indian Creek), 006_02 (Mason Creek), 007_04 (Fifteenmile Creek), 008_03 (Tenmile Creek), 33

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

010_03 (Fivemile Creek), 017_03 (Sand Hollow Creek) contribute sediment concentrations to the Boise River that exceed TMDL mainstem targets. It is possible that apparent sediment impairment in Fifteenmile Creek is a result of loads contributed from Fivemile and Tenmile Creeks, each of which is in a unique AU. Sediment data collected from some LA control monitoring locations in 2008 was compared to the TMDL target loads (Table 14). At locations where TMDL sediment LAs were met, the data was then compared with other data from the appropriate AU to determine if beneficial use attainment had been met throughout the AU. While some LA control locations appear to have met TMDL sediment targets, data collected from other locations (East and West Hartley Gulch and Thurman Drain) in 2005 and 2008 indicate that AU 005_06 is still contributing sediment in concentrations likely to exceed turbidity criteria and that exceed TMDL allocations to the Boise River. Table 14. Load analysis of suspended sediment (SSC or TSS) data collected at some Lower Boise River subbasin TMDL Load Allocation (LA) locations in 2008. Control Location Eagle Drain Thurman Drain Fifteenmile Creek Star Feeder Long Feeder Watts Creek Mill Slough Willow Creek

AU

Date

Discharge (cfs)

Average Concentration (mg/L)

005_06 005_06 007_04 005_06 005_06 005_06 005_06 015_03

2000 2008 2005

17.675 56.4 81.75 No data No data No data 102.5 26

2005 2005

Coefficient

Load Tons/day

TMDL Target Tons/day

23.25 9.3 73 No data No data No data 19.25 18.5

0.0027 0.0027 0.0027

1.11 1.42 16.11 No data No data No data 5.33 1.30

1.61 0.34 18.02 1.73 0.35 0.28 7.08 2.28

0.0027 0.0027

Mason Slough

006_02

2005

4.8

107.75

0.0027

1.40

1.2

Mason Creek E. and W. Hartley Gulch E. and W. Hartley Gulch Indian Creek Conway Gulch Dixie Drain

006_02 005_06

2000 2005

120.5 51

230.3 45.5

0.0027 0.0027

74.93 6.27

21.48 5.31

005_06

2008

26.43

367.37

0.0027

26.22

5.31

002_04 001_06 001_06

2005 2005 2005

47.5 32 197

60.25 231.9 67.75

0.0027 0.0027 0.0027

7.73 20.04 36.04

5.74 7.14 25.91

Access to the confluence of tributaries and drains in the subbasin is difficult, and access does not ensure that data collection is possible, so DEQ reviews data from multiple sources, including remote data such as satellite imagery, to determine compliance with criteria and TMDLs. Satellite images are not difficult or expensive to obtain and can provide information at a glance to determine whether sediment loads are entering streams. The images in Figure 10 were obtained from Google Earth in March 2008 and metadata from Google Earth state that the coverage for the region of interest was collected in 2006. It is evident that sediment plumes from specific drains and tributaries in the Lower Boise River subbasin contribute significant sediment and effluent loads (not related to WWTPs) to the Boise and Snake Rivers, as seen in the images in Figure 10.

34

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Sediment plume at Sand Hollow Creek confluence with the Snake River.

Effluent (not from WWTP) plume at Indian Creek confluence with the Boise River.

35

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Sediment plume at Conway Gulch confluence with the Boise River.

Effluent (not from WWTP) plume at East and West Hartley Gulch confluence with the Boise River. 36

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Sediment plume at Fifteenmile Creek confluence with the Boise River. Figure 10. Satellite images of sediment plumes from drains and tributaries in the Lower Boise River subbasin. Images collected from Google Earth, March 2008. Another way to analyze the behavior of suspended sediment in the Lower Boise River subbasin is to develop sediment load duration diagrams to analyze sediment concentrations at all flow stages. Load duration diagrams for a pollutant of concern are developed by plotting the data and numeric water quality targets on flow duration curves. A flow duration curve is a graphical depiction of the frequency of specific flow rates using cumulative flow data over a specific period of time. Flow duration curves represent the probability of a certain flow volume being exceeded as a percent of time flow values have been equaled or exceeded in the past. High flows in the Lower Boise River subbasin are depicted between the zero and tenth percentile; moist conditions are between the tenth and 40th; mid-range flow is between the 40th and 60th; dry conditions are between the 60th and 90th; and low flows are between the 90th and 100th percentile. In most natural systems, low flows are exceeded a majority of the time and peak flows are exceeded infrequently. Load duration diagrams can reveal patterns of impairment, the response of a pollutant across all flow conditions, and data gaps. Loads from point sources usually plot on duration or probability diagrams as an increase during low flows, while loads from nonpoint sources usually follow the natural flow pattern--increasing during higher flows. Figure 11 depicts the load duration diagram for suspended sediment at the TMDL control

37

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

monitoring location near Middleton. Because there are no data points for suspended sediment at the lowest and highest flow conditions, it is not possible to determine a pattern of behavior for suspended sediment at those flow conditions. However, with the limited data available, it appears that nonpoint sources contribute to suspended sediment loads at this location of the mainstem river.

Figure 11. Sediment Load Duration Diagram from Lower Boise River TMDL Control Monitoring Location, Boise River near Middleton, 2003-2008. Data collected from some WLA control monitoring locations in 2008 was compared to the TMDL target loads. Notus is the only location where the WLA described in the TMDL was not met, based on an evaluation of data from 2008. Table 15. Load analysis of suspended sediment, data collected at Lower Boise River subbasin TMDL WLA locations in 2008. Control Location Lander Meridian Boise West Middleton Nampa Caldwell

AU 011a_06 005_06 005_06 005_06 005_06 001_06

Date 5/2008 5/2008 5/2008 5/2008 5/2008 5/2008

Discharge (cfs)

Average Concentration (mg/L)

20 4.9 33 0.428 10.29 5.18

0.8 2 5.4 37 6 8

38

Coefficient 0.0027 0.0027 0.0027 0.0027 0.0027 0.0027

Load Tons/day 0.04 0.03 0.04 0.04 0.17 0.11

TMDL Target Tons/day 17 .355 3.1 0.535 1.5 1.0625

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Control Location Star Notus

AU 005_06 001_06

Date 5/2008 2/2008

Discharge (cfs)

February 2009

Average Concentration (mg/L)

0.633 0.546

7 36

Coefficient

Load Tons/day

0.0027 0.0027

TMDL Target Tons/day

0.01 0.05

The city of Nampa collects total suspended solids (TSS) samples from Indian Creek (AU 002_04) in compliance with the WWTP point source NPDES permit and results of sample analysis is represented in Figure 12. Based on the data provided for this review, the WWTP meets the TMDL sediment targets. In most cases, the WWTP effluent does not significantly alter the concentration or load of sediment in this AU (002_04), and in a few instances the discharge may be serving to dilute higher concentrations of sediment upstream of the WWTP. Indian Creek Total Suspended Solids (TSS) Concentrations, AU 002_04, 2003-2007

12 /3 0/ 0 3/ 2 30 /0 6/ 3 28 /0 9/ 3 26 12 /0 3 /2 5/ 0 3/ 3 24 /0 6/ 4 22 /0 9/ 4 20 / 12 0 4 /1 9/ 0 3/ 4 19 /0 6/ 5 17 /0 9/ 5 15 / 12 0 5 /1 4/ 0 3/ 5 14 /0 6/ 6 12 /0 9/ 6 10 /0 12 6 /9 /0 6 3/ 9/ 07 6/ 7/ 07 9/ 5/ 0 12 7 /4 /0 7

TSS (mg/L)

Data Collected by City of Nampa

90 80 70 60 50 40 30 20 10 0

Date Upstream

Downstream

14-day maximum

60 day maximum

Figure 12. Graph of total suspended solids (TSS) concentration data from Indian Creek (AU 002_04) near the wastewater treatment plant (WWTP) in Nampa, 20032007. Bacteria Bacteria concentrations are used as a surrogate measure to evaluate attainment of contact recreation designated uses. Primary contact recreation (PCR) is a year-round designated beneficial use of the Lower Boise River and the TMDL compliance locations are the USGS gage locations at Glenwood Bridge, Middleton and Parma. Because the TMDL determined that some locations in the subbasin required more than a 90% reduction in loads the WAG applied for grant funds to conduct a study to determine the proportion of contributing sources throughout the subbasin. A copy of a bacteria DNA ribo-typing study (LBRWQP, 2003) is available at http://www.lowerboisewatershedcouncil.org/05_water-quality/sedbacteria/dna_test/DNA_Rpt_Final.pdf. Even though approximately 30% of the DNA was from source(s) that were not identifiable using the study methods, it was determined that controllable sources of 39

0.0965 0.0165

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

bacteria represent 27 to 56% of the load in the Lower Boise River subbasin, with humans, livestock and pets contributing the largest fraction of bacteria (LBRWQP, 2003). The TMDL selected maximum geomean concentrations at the control monitoring locations as the target for compliance determination. The city of Boise collected data to calculate bacteria geomean concentrations from the Glenwood control location in 2003 and 2004 (Figure 13), and from the Middleton (Figure 14) and Parma (Figure 15) control locations in 2005. Data from additional mainstem river locations in AUs 011a_06, 005_06 and 001_06 was also collected. The geomean and instantaneous data indicate that in all AUs sampled bacteria TMDL targets and state standards for PCR have been exceeded several times in the past five years. Geomean Bacteria Data, AU 011a_06, Lower Boise River, 2003-2004 Data Collected by the city of Boise

E. coli (cfu/100 mL)

140 120 100 80 60 40 20 0 03 1/ 3/

3 /0 0 3 4/

3 /0 9 2 6/

3 /0 8 2 8/

10

03 7/ /2

12

03 6/ /2

4 /0 4 2 2/

4 /0 4 2 4/

4 /0 3 2 6/

4 /0 2 2 8/

4 /0 21 / 10

Date

Eckert Road Veterans Parkway Bridge Geomean Maximum

Marden Bridge Glenwood Bridge

Figure 13. Geomean Bacteria Data Collected by the City of Boise from AU 011a, Lower Boise River, 2003 and 2004.

40

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Geomean Bacteria Data, AU 005_06, Lower Boise River, 2003-2006 Data Collected by the city of Boise 300

E. coli (cfu/100 mL)

250 200 150 100 50

3/ 1/ 0 4/ 3 30 /0 6/ 3 29 /0 8/ 3 28 / 10 0 3 /2 7/ 12 03 /2 6/ 0 2/ 3 24 /0 4/ 4 24 /0 6/ 4 23 /0 8/ 4 22 / 10 0 4 /2 1/ 12 04 /2 0/ 0 2/ 4 18 /0 4/ 5 19 /0 6/ 5 18 /0 8/ 5 17 / 10 0 5 /1 6/ 12 05 /1 5/ 05

0

Date

Boise R. at Eagle Boise R. near Caldwell

Boise R at Middleton Geomean Maximum

Figure 14. Geomean Bacteria Data Collected by the City of Boise from AU 005, Lower Boise River, 2003 through 2005. Geomean Bacteria Data, AU 001_06, Lower Boise River, 2003-2006 Data Collected by the city of Boise 300

E. coli (cfu/100 mL)

250 200 150 100 50 0

/0 5 8/ 20

9/ 05 10 /1

Geomean Maximum

Date

8/ 05 12 /1

Boise R. near Parma

Figure 15. Geomean Bacteria Data Collected by the City of Boise from AU 001, Lower Boise River, 2005.

41

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Instantaneous bacteria data, summarized in the following figures, also indicate that bacteria concentrations remain an issue for attainment of PCR and SCR beneficial uses in the subbasin. At the Boise River near Glenwood control location designated use criteria for PCR are not exceeded, and criteria are exceeded seasonally at the Middleton and Parma locations (Figure 13, Figure 14 and Figure15). In the TMDL, the tributaries and drains were assigned LAs at their confluences with the Lower Boise River mainstem. As depicted in Figure 17 and Figure 18, all tributaries and drains exceed the designated beneficial use criteria for PCR and SCR, with Fifteenmile Creek contributing the greatest tributary load and Dixie Drain contributing the greatest load of the three sampled drains. It is not possible to determine trends with the limited data from tributary and drain locations; nor is it possible to determine what percent reduction has been achieved in the subbasin because of the change in standards from fecal coliform to E. coli concentrations. The most useful method of determining TMDL target achievement is to quantify the exceedance of current data over criteria (Figure 16, Figure 17 and Figure 18). The river locations indicate no significant change in bacteria load over the past five years, with the highest concentrations occurring during the summer months at mainstem TMDL control locations (Figure 16).

Lower Boise River E. coli Concentrations, 2003-2008 E. coli Concentration (cfu/100 mL)

10000

100

1 02

/01

/03 1/03 9/03 7/04 6/04 3/04 1/05 1/05 8/05 6/06 6/06 3/06 1/07 1/07 8/07 6/08 /2 /0 /2 /2 /2 /2 /1 /2 /1 /1 /1 /1 /1 /0 /0 09 06 01 05 09 01 05 09 01 05 09 01 05 09 01

Date BR at Diversion BR at Star Bridge BR near Parma Primary Contact Instantaneous Maximum

BR at Glenwood BR above Middleton Primary Contact Geometric Mean Maximum

Figure 16. Graph of bacteria data collected from Lower Boise River locations, 2003 to 2008.

42

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Lower Boise River Tributary E. coli Concentrations, 2005

E. coli Concentration (cfu/100 mL)

10000

1000

100

10

1 04/29/05

06/28/05 Date Fivemile Ck Fifteenmile Ck Mason Ck Secondary Contact Geometric Mean Maximum

Tenmile Ck Willow Ck Indian Ck Secondary Contact Instantaneous Maximum

Figure 17. Graph of bacteria data collected from selected Lower Boise River tributaries, 2005.

Lower Boise River Drains E. coli Concentrations, 2005

E. coli Concentration (cfu/100 mL)

10000

1000

100 05/01/05

05/31/05

06/30/05

07/30/05

Date Mill Slough Dixie Drain Secondary Contact Instantaneous Maximum

Conway Gulch Secondary Contact Geometric Mean Maximum

Figure 18. Graph of bacteria data collected from three Lower Boise River drains, 2005.

43

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

The city of Nampa provided recent E. coli sample analysis data from upstream and downstream of the city’s WWTP on Indian Creek (AU 002_04). Bacteria concentrations upstream of the WWTP exceed beneficial use criteria. While the sample set is too small to arrive at definitive conclusions, it does appear that permitted point source effluent can have a dilution effect on some systems and reduce bacteria loads directly downstream of the permitted point source. A load duration diagram for bacteria at the mainstem TMDL control location near Middleton indicates that there are no significant data gaps for bacteria and the load is consistent across all flow conditions (Figure 19). This indicates a consistent source of bacteria to the mainstem system near this location. While agricultural drains are defined by the CWA as nonpoint sources, conveyance structures deliver nonpoint source effluent to the Boise River at specific points, so there are instances where nonpoint source pollutants may resemble point source patterns on a load duration diagram. Lower Boise River Water Quality Load Duration Analysis (2003 - 2008)

Site: 13213000

100000

High Flows

E.coli (#/100mL)

10000

Moist Conditions

Mid-range Flows

Dry Conditions

Low Flows

A ll D at a

1000

A pr-O ct >50% Sto rmf lo w M edian

100

Geo M ean

10

1

0

10

20

30

40

50

60

70

Flow Duration Interval (%)

DEQ Data & Gage 13213000 Duration Interval

80

90

100

3970 square miles

Figure 19. Bacteria Load Duration Diagram for Lower Boise River mainstem TMDL control monitoring location near Middleton. Based on a review of the available data, the water quality standard for bacteria is exceeded in AUs 002_04 (Indian Creek), 005_06 (Boise River and Mill Slough), 006_02 (Mason Creek), 007_04 (Fifteenmile Creek), 008_03 (Tenmile Creek), 010_03 (Fivemile Creek), 011a_06 (Boise River), 015_03 (Willow Creek) and 017_03 (Sand Hollow Creek).

44

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Temperature Water temperature effects the attainment of beneficial uses for cold-water aquatic life (COLD) and salmonid spawning (SS) in the Lower Boise River subbasin. Information from the mid-1800s indicates that the subbasin supported a thriving salmonid fishery (ISHS, 1993). Even though geothermal groundwater sources exist in the Lower Boise River subbasin, hot springs are not discharging into surface waters in a way that influences surface water temperatures. Geothermal sources occur along the Boise Front, headwaters of Indian Creek, and in various locations near the confluence with the Snake River. A flow contribution analysis indicates that approximately 0.03% of identified Lower Boise River subbasin surface water receives water from geothermal sources. Except for AU 011b, the mainstem Boise River must meet the temperature criteria for SS beneficial use, and AU 011b must meet the criteria for COLD beneficial use. The appropriate time period for the species of salmonids in the Lower Boise River subbasin was determined using the time frames specified in the WBAG II (Grafe, et. al, 2002) and verifying that time frame with the Idaho Department of Fish and Game (Jeff Dillon, IDFG, personal communication, January 22, 2009). As described in the WBAG II (Grafe, et al., 2002), if the temperature exceedance of numeric criteria is less than 10% and there is no other evidence of thermal impairment, delisting for temperature pollution may be considered. Idaho WQS provide an exemption for numeric temperature criteria exceedance in the event that air temperature is above the ninetieth percentile of a yearly series of maximum weekly maximum air temperatures (MWMT) calculated over the historic record from the nearest weather reporting station (IDAPA 58.01.02.03). Air temperature data has been collected in the subbasin from the early 1900s and the most recent 35 years are summarized in Figure 20.

- Extreme Max. is the maximum of all daily maximum temperatures recorded for the day of the year. - Ave. Max. is the average of all daily maximum temperatures recorded for the day of the year. - Ave. Min. is the average of all daily minimum temperatures recorded for the day of the year. - Extreme Min. is the minimum of all daily minimum temperatures recorded for the day of the year.

Figure 20. Graph of daily air temperatures from 1973-2007 as retrieved from the Western Regional Climate Center for the Boise 7N weather station. 45

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

The city of Boise collected continuous water temperature data from several locations in the subbasin and has shared the data for use in this review as a professional courtesy. The data qualifies as Tier I data and can be used to make beneficial use attainment determinations. The daily maximum and daily average temperatures from the city locations for the past five years are presented in Figure 21, Figure 22, Figure 23 and Figure 24. Based on the data collected over the past five years, it appears that water temperature at all but one location in the Lower Boise River subbasin exceeds numeric criteria at some time of every year. The City of Boise and the USGS also collected continuous water temperature in 2004 from several drains and tributaries in the subbasin but the data has not been stored in the USGS database and is not available to the public. The city of Boise public works department created a report (City of Boise, 2005) using data collected in 2004. The averaged values reported by the City of Boise and included in an abridged format in the appendices of this report parallel the Tier I data presented in this report. Most locations generally exceed temperature criteria from April through August and for brief periods between September and November. However, the TMDL monitoring location near Middleton exceeded criteria for two out of five years (2003, 2004) as early as mid-March, and in 2005 criteria was exceeded in mid-February. Because most of the criteria exceedances occur in late fall and early spring, it is unlikely that the air temperature exemption would apply to the locations and /or time periods that routinely exceed temperature criteria. Daily Maximum Water Temperature Lower Boise River, 2003-2008 Data collected by City of Boise 30 Water Temperature (*C)

25 20 15 10 5

/0 7

/0 7

/1 4 12

/0 7

/2 0 09

/2 7 06

/0 3

/0 7

/0 7 04

/0 6

/0 8 01

10

07

/1 5

/0 6

/0 6

/2 2

/0 6 04

/2 8

/0 5

/0 2 02

/0 9

/1 6

11

/2 3

/0 5

/0 5 08

/0 5 05

02

/2 7

/0 4

/0 4

/0 4 12

/0 4 09

/1 0

/0 4

/1 7 06

/2 4 03

12

/3 0

/0 3

0

Date BR at Marden Bridge BR at Eagle COLD Daily Maximum Criteria

BR at Veterans Parkway BR at Middleton

Br at Glenwood SS Daily Maximum Criteria

Figure 21. Graph of daily maximum water temperature of Lower Boise River locations compared to water quality standards for salmonid spawning, 2003-2008.

46

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Daily Maximum Water Temperature of Boise River COLD Designated Use Locations, 2003-2008 Data collected by City of Boise 30 Water Temperature (*C)

25 20 15 10 5

1/ 1/

20 4/ 03 1/ 2 6/ 003 30 /2 9/ 003 28 / 12 200 /2 3 7/ 20 3/ 0 26 3 /2 6/ 004 24 /2 9/ 004 22 12 /20 /2 04 1/ 2 3/ 004 21 /2 6/ 005 19 /2 9/ 005 17 / 12 200 /1 5 6/ 20 3/ 0 16 5 /2 0 6/ 0 14 6 /2 9/ 006 12 12 /20 /1 06 1/ 2 3/ 006 11 /2 0 6/ 07 9/ 20 9/ 07 7/ 2 12 007 /6 /2 00 7

0

Date BR at Lucky Peak

BR at Parma

COLD Daily Maximum Criteria

Figure 22. Graph of daily maximum water temperature at Boise River below Lucky Peak outfall and Boise River near Parma compared to water quality standards for cold-water aquatic life 2003-2008. Daily Average Water Temperature Lower Boise River, 2003-2008 Data collected by City of Boise Water Temperature (*C)

25 20 15 10 5

/4 /

07

07 12

8/ 6/

07 4/ 8/

06

/0 6

/0 6

/9 / 12

8/ 11

4/ 13

/0 5 /1 4

/0 5

12

/0 4

/0 5

8/ 16

4/ 18

/1 9

/0 4

/0 3

/0 4

12

8/ 21

4/ 23

/2 5

/0 3

/0 3

12

8/ 27

4/ 29

12

/3 0

/0 2

0

Date BR at Marden Bridge Br at Glenwood BR at Middleton COLD Daily Average Maximum Criteria

BR at Veterans Parkway BR at Eagle SS Daily Average Maximum Criteria

Figure 23. Graph of daily average water temperature of Lower Boise River locations compared to the water quality standards for salmonid spawning and coldwater aquatic life, 2003-2008.

47

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Daily Average Water Temperature of Boise River COLD Designated Use Locations, 2003-2008 Data collected by City of Boise Water Temperature (*C)

30 25 20 15 10 5

/4 /

07

07 12

8/ 6/

07 4/ 8/

06

/0 6

/0 6

/9 / 12

8/ 11

/0 5

4/ 13

/1 4

/0 5

/0 4

/0 5

12

8/ 16

4/ 18

/1 9

/0 4

/0 3

/0 4

12

8/ 21

4/ 23

/2 5

/0 3

/0 3

12

8/ 27

4/ 29

12

/3 0

/0 2

0

Date BR at Parma

BR at Lucky Peak

COLD Daily Average Maximum Criteria

Figure 24. Graph of daily average water temperature at Boise River below Lucky Peak outfall and Boise River near Parma compared to the water quality standards for cold-water aquatic life, 2003-2008. Instantaneous temperature data collected by the USGS, ISDA, and city of Nampa are presented in Figure 25, Figure 26, Figure 27, Figure 28 and Figure 29. Temperature (*C) at USGS gage locations in Lower Boise River, 2003-2008

Water Temperature (*C)

30.0

20.0

10.0

01 /0 1/ 03 05 /0 1/ 03 08 /2 9/ 03 12 /2 7/ 03 04 /2 5/ 04 08 /2 3/ 04 12 /2 1/ 04 04 /2 0/ 05 08 /1 8/ 05 12 /1 6/ 05 04 /1 5/ 06 08 /1 3/ 06 12 /1 1/ 06 04 /1 0/ 07 08 /0 8/ 07 12 /0 6/ 07

0.0

Date BR at Glenwood *SS Daily Maximum Criteria

BR at Star COLD Daily Maximum Criteria

BR above Middleton

Figure 25. Graph of instantaneous water temperature reported by the USGS and ISDA compared to water quality standards for salmonid spawning designated uses, 2003-2008.

48

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Temperature (*C), Boise River, COLD designated locations, 2003-2008

Water Temperature (*C)

30.0

20.0

10.0

01 /0 1/ 03 05 /0 1/ 03 08 /2 9/ 03 12 /2 7/ 03 04 /2 5/ 04 08 /2 3/ 04 12 /2 1/ 04 04 /2 0/ 05 08 /1 8/ 05 12 /1 6/ 05 04 /1 5/ 06 08 /1 3/ 06 12 /1 1/ 06 04 /1 0/ 07 08 /0 8/ 07 12 /0 6/ 07

0.0

Date BR at Diversion

BR near Parma

COLD Daily Maximum Criteria

Figure 26. Graph of instantaneous water temperature reported by the USGS and ISDA compared to water quality standards for cold-water aquatic life designated uses, 2003-2008. Lower Boise River Tributary Temperature (*C) at USGS and ISDA locations, 2005

Water Temperature (*C)

30.0

25.0

20.0

15.0

10.0

5.0 04/15/05

05/15/05

06/14/05

07/14/05

08/13/05

Date *Fivemile Ck *Mason Ck *Site Specific Daily Maxiumum

*Tenmile Ck Willow Ck COLD Daily Maximum

*Fifteenmile Ck *Indian Ck

Figure 27. Graph of instantaneous water temperature reported by the USGS and ISDA, compared to water quality standards for site-specific(*) and cold-water aquatic life beneficial uses, 2005.

49

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Lower Boise River Drains Temperature (*C) at USGS and ISDA locations, 2003-2005

Water Temperature (*C)

25.0

20.0

15.0

10.0 04/20/03

08/18/03

12/16/03

04/14/04

08/12/04

12/10/04

04/09/05

08/07/05

Date *Mill Slough Dixie Drain COLD Daily Maximum Criteria

Conway Gulch *SS Daily Maximum Criteria

Figure 28. Graph of instantaneous water temperature reported by the USGS and ISDA compared to water quality standards for cold-water aquatic life and salmonid spawning beneficial uses, 2003-2005. * Applies to water bodies in AU_005 (Mill Slough). Indian Creek Water Temperature, AU 002_04, 2003-2008 Data Collected by city of Nampa

Water Temperature (*C)

30 25 20 15 10

01 /0 1/ 04 03 /0 1/ 06 03 /3 0/ 09 03 /2 8/ 12 03 /2 7/ 03 03 /2 6/ 06 04 /2 4/ 09 04 /2 2/ 12 04 /2 1/ 03 04 /2 1/ 06 05 /1 9/ 09 05 /1 7/ 12 05 /1 6/ 03 05 /1 6/ 06 06 /1 4/ 09 06 /1 2/ 12 06 /1 1/ 03 06 /1 1/ 06 07 /0 9/ 09 07 /0 7/ 12 07 /0 6/ 07

5

Date Upstream

Downstream

COLD Daily Maximum Criteria

Figure 29. Graph of instantaneous water temperature (2003-2007) in Indian Creek, upstream and downstream of the wastewater treatment plant, reported by the city of Nampa, compared to water quality standards applicable to AU 002_04. Temperature data collected by the city of Nampa near the WWTP between 2003 and 2007 indicate exceedance of designated beneficial use criteria in spring and fall months

50

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

every year (Figure 29). Temperature data collected near stormwater discharge locations in the Boise area were within the established permit limits. Instantaneous temperature data compared to the continuous data provides less detail regarding water temperature in the subbasin, but does document some exceedance of beneficial use criteria at a few locations throughout the subbasin in the spring. Sporadic point source data offers limited usefulness in identifying sources of thermal flux, such as ponds, diversions, reservoirs, tributaries, drains, hyporheic flow zones, springs and etc. Although half of the increase in mainstem water temperature takes place between the outfall of Lucky Peak Dam and Glenwood Bridge, water temperature in the mainstem continues to warm to Middleton, and then cools only slightly to the confluence with the Snake River. Based on a review of all available data, water temperature exceeds beneficial use criteria in AUs 001_06, 002_04, 005_06 and 011a_06. Benthic Macroinvertebrate Data In accordance with the WBAG II (Grafe, et. al., 2002), benthic macroinvertebrate data may be used to infer temperature regimes as cold, cool, warm, or hot by using an appropriate index to identify the temperature tolerance of the dominant species. While the USGS data tabulated below (Table 16) cannot be used to make use attainment determinations because samples were collected outside the protocol timeframe, it is relevant to this review and is considered as Tier II data. Table 16. Summary of benthic macroinvertebrate (5-riffle composite) data collected by the USGS from mainstem Lower Boise River, 2003-2006. Temperature tolerance indices compiled by DEQ. Boise River Below Eckert Road, USGS 13203760-AU 011a_06 Water Year 2003 2004 2005 2006 Date 10/25/2002 11/10/2003 10/26/2004 10/31/2005 Cold 19 40 125 32 Cool 306 56 317 197 Warm 7,297 1,601 4,320 3,485 Hot 0 0 0 0 unclassified 5,088 2,999 5,252 2,802 Temperature Tolerance total 7,622 1,697 4,762 3,714 classified %Cold 0 2 3 1 %Cool 4 3 7 5 %Warm 96 94 91 94 %Hot 0 0 0 0 Boise River at Glenwood Bridge, USGS 13206000-AU 011a_06 Date 10/24/2002 10/28/2003 10/26/2004 11/7/2005 Cold 0 0 0 0 Cool 83 131 213 16 Warm 5,334 2,479 3,214 1,079 Hot 0 4 7 2 Date 10/24/2002 10/28/2003 10/26/2004 11/7/2005 unclassified 3,839 3,573 4,397 712

51

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Water Year total classified %Cold %Cool %Warm %Hot

February 2009

Temperature Tolerance 2003 2004 2005

2006

5,417 0 2 98 0

1,097 0 1 98 0

2,614 0 5 95 0

3,434 0 6 94 0

Boise River at Middleton, USGS 132010050-AU 005_06 Date 10/24/2002 10/28/2003 10/26/2004 11/7/2005 Cold 16 10 0 5 Cool 432 127 156 45 Warm 1,216 954 816 367 Hot 14,160 7,504 10,440 1,018 unclassified 448 75 804 111 total 5,417 2,614 3,434 1,097 classified %Cold 0 0 0 0 %Cool 3 1 1 3 %Warm 8 11 7 26 %Hot 89 87 91 71 Boise River at Caldwell, USGS 13211000-AU 005_06 Date 10/24/2002 11/20/2003 11/23/2004 11/8/2005 Cold 0 0 2 0 Cool 159 304 61 10 Warm 1,958 1,889 1,188 177 Hot 170 2,885 35 1 unclassified 1,232 116 882 146 Temperature Tolerance total 2,287 5,078 1,286 188 classified %Cold 0 0 0 0 %Cool 7 6 5 5 %Warm 86 37 92 94 %Hot 7 57 3 1 Boise River at Parma, USGS 13213000-AU 001_06 Date 10/23/2002 10/27/2003 11/24/2004 11/17/2005 Cold 38 6 12 0 Cool 1,882 342 218 37 Warm 3,024 587 671 1,000 Hot 250 524 71 5 unclassified 587 87 1,738 584

52

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Water Year total classified %Cold %Cool %Warm %Hot

February 2009

Temperature Tolerance 2003 2004 2005

2006

5,194 1 36 58 5

1,042 0 4 96 <1

1,459 0 23 40 36

972 1 22 69 7

Benthic macroinvertebrate data was also collected from the subbasin through the BURP in 2003 and qualifies as Tier I data. A summary is presented in Table 17, by BURP site ID and associated AU. Table 17. Summary of temperature tolerance statistics of benthic macroinvertebrate organisms collected by DEQ through the Beneficial Use Reconnaissance Program (BURP), 2003. Stream and AU BURP ID Indian Creek at 2003SBOIA051 Robinson RoadAU 003a_04 Mason Creek at 2003SBOIA050 Lakeview ParkAU 006_02 Fivemile Creek at 2003SBOIA052 Meridian RoadAU 010_03

Date

Water Temperature (*C) %Cold

%Cool

%Warm

%Hot

10/14/03

13.5

<1

14

86

10/15/03

11.3

<1

13

87

10/14/03

14.9

34

66

The Tier I macroinvertebrate data indicate that Lower Boise River AUs 003a_04, 006_02 and 010_03 are dominated by organisms that prefer hot water. AUs 006 and 010 are designated for MOD beneficial use (not approved by EPA) and must meet criteria of 26 °C daily maximum, and 23 °C daily average maximum. AU 003a_04 is designated for SS, COLD, and SCR. Using the guidelines in the WBAG II (Grafe, et al., 2002), and absent any data to the contrary, an extrapolation of temperature data can be made across the AU in which data was collected. Based on a review of the available data, it does not appear that temperature criteria are exceeded in AU 006_02 or 010_03. Fish Data Water temperature and other habitat measures can also be inferred from an analysis of fish communities observed in water bodies. The USGS collected fish community data from the Lower Boise River mainstem at the same locations as benthic macroinvertebrate data, and this data can be used in a manner consistent with the macroinvertebrate data. DEQ also collected fish community data from two sites in the subbasin in 2003 as part of the BURP. Table 18 summarizes the temperature tolerance of the fish species collected by the USGS and DEQ from 2003 and 2004.

53

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table 18. Summary of temperature tolerance of fish community data collected by the USGS and DEQ between 2003 and 2004. Site Name Lower Boise River below Eckert Road Lower Boise River above Lander Street WWTP Lower Boise River below Lander Street WWTP Boise River at Glenwood Bridge Lower Boise River above West Boise WWTP Lower Boise River below West Boise WWTP

AU Site ID

Date Collected

AU 011a_06 4333571160800

11/17/2003

20

80

AU 011a_06 4336571161321

11/18/2003

53

47

AU 011a_06 4338281161459

11/18/2003

61.3

38.4

AU 011_06 13209500

8/18/2004

24.8

AU 005_06 4340121161823

11/19/2003

AU 005_06 4340301162020

11/19/2003

%Cold %Cool %Warm % Salmonids USGS Data 0

Individuals Collected

20

854

47

524

0.3

61.3

284

74.1

1.1

24.8

173

99

0.9

0.1

89

384

83.5

15.5

1

83.5

291

BURP Data Indian Creek at Robinson RoadBlacks Creek at Meridian Rd

AU 003a_04 2003SBOIA050

10/14/03

100

0

21

AU 009_02 2003SBOIA052

10/14/03

100

0

63

Except for the data collected at Glenwood Bridge in 2004, fish data collected by the USGS can be used as Tier II data. The Glenwood Bridge (TMDL control monitoring location) fish data correlated with the water temperature and benthic macroinvertebrate data indicate that COLD is not a supported use in AU 011a_06. Dissolved Oxygen Dissolved oxygen (DO) is another parameter with numeric WQS criteria used to determine attainment of beneficial uses in the Lower Boise River subbasin. DO data was collected by the same entities as other data reviewed for this report and Figure30, Figure 31 and Figure 32 summarize the DO data reviewed for this report. Based on the data collected by the USGS and ISDA, beneficial use criteria for DO are met in all monitored AUs.

54

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Dissolved Oxygen (DO) at USGS gage locations in Lower Boise River, 2003-2008

Dissolved Oxygen (mg/l)

15

11

7

/0 7 8/ 8/ 07 12 /6 /0 7

/0 6

4/ 10

/0 6

/1 1

12

/0 6

8/ 13

/0 5

4/ 15

/1 6

/0 5

12

/0 5

8/ 18

/0 4

4/ 20

/0 4

/2 1

12

/0 4

8/ 23

/0 3

4/ 25

/0 3

/2 7

12

03

8/ 29

5/ 1/

1/ 1/

03

3

Date BR at Diversion BR above Middleton

BR at Glenwood BR near Parma

BR at Star Site Specific / COLD Minimum

Figure 30. Graph of instantaneous dissolved oxygen concentrations reported by the USGS from Lower Boise River gage locations, 2003-2008. Lower Boise River Tributary Dissolved Oxygen (DO) at USGS locations, 2005

Dissolved Oxygen (mg/l)

9

7

5

3 04/15/05

05/15/05

06/14/05

07/14/05

08/13/05

Date Fivemile Ck Willow Ck Site Specific / COLD Minimum

Tenmile Ck *Mason Ck *Site Specific Minimum

Fifteenmile Ck *Indian Ck

Figure 31. Graph of instantaneous dissolved oxygen reported by the USGS from Lower Boise River tributary locations, 2003and 2005.

55

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Lower Boise River Drains Dissolved Oxygen (DO) at USGS and ISDA locations, 2003- 2005

Dissolved Oxygen (mg/l)

9

7

5

3 04/20/03

08/18/03

12/16/03

04/14/04

08/12/04

12/10/04

04/09/05

08/07/05

Date Mill Slough

Conway Gulch (DO)

Dixie Drain (DO)

Minimum DO

Figure 32. Graph of instantaneous dissolved oxygen reported by the USGS and IDA from select Lower Boise River drains 2003 and 2005. pH The criterion for pH is intended to protect aquatic life beneficial uses (COLD, SS, MOD (not approved by EPA), etc.). pH data was collected by the USGS, ISDA, city of Nampa, BOR and DEQ at several locations in the subbasin. The following graphs compare the data collected in the past five years to the numeric beneficial use criteria specified for each AU or site in the WQS (Figure 33 and Figure 34). Based on the data collected, the Boise River at Glenwood Bridge is the only location that has exceeded pH criteria in the past five years (Figure 35).

56

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Lower Boise River pH values, 2003-2008 9.5 9 8.5

pH

8 7.5 7 6.5 6 5.5

2/ 1/ 20 03 6/ 1/ 20 03 9/ 29 /2 00 3 1/ 27 /2 00 4 5/ 26 /2 00 4 9/ 23 /2 00 4 1/ 21 /2 00 5 5/ 21 /2 00 5 9/ 18 /2 00 5 1/ 16 /2 00 6 5/ 16 /2 00 6 9/ 13 /2 00 6 1/ 11 /2 00 7 5/ 11 /2 00 7 9/ 8/ 20 07 1/ 6/ 20 08

5

Date BR at Diversion BR near Parma

BR at Glenwood pH minimum

BR at Star pH maximum

BR above Middleton

Figure 33. pH data collected from mainstem Boise River locations by the USGS from 2003 to 2008. Lower Boise River Triburary pH Values, 2003-2008 9.5

8.5

pH

7.5

6.5

5.5

4.5 4/15/2005

5/15/2005

6/14/2005

7/14/2005

8/13/2005

Date Fivemile Ck

Tenmile Ck

Fifteenmile Ck

Willow Ck

Mason Ck

Indian Ck

pH minimum

pH maximum

Figure 34. pH data collected by the USGS from Lower Boise River tributaries, 2005.

57

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Lower Boise River Drains pH Values, 2003-2008 9.5

8.5

pH

7.5

6.5

5.5

4.5 4/23/2003

8/21/2003 12/19/2003 4/17/2004

8/15/2004 12/13/2004 4/12/2005

8/10/2005

Date Mill Slough pH minimum

Conway Gulch pH maximum

Dixie Drain

Figure 35. pH data collected by ISDA and the USGS from Lower Boise River drains, 2003 and 2005. Based on data reviewed for this report, pH criteria for beneficial uses are met at all locations in the subbasin. Ammonia Ammonia concentration criteria are intended to protect aquatic life beneficial uses. The criteria are dependent on pH, with a maximum acute concentration (CMC) criterion and a maximum chronic criterion (CCC). The USGS, ISDA, BOR, city of Nampa and DEQ collected ammonia data from several locations in the subbasin between 2003 and 2008. Figure 36, Figure 37 and Figure 38 are graphs of collected data. Figure 39 is a graph of data from Indian Creek (AU 002_04), collected by the city of Nampa. As none of the reported analytical results exceed criteria, there are no maximum criteria lines on the graphs.

58

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Boise River Ammonia (N) Concentrations, 2003-2008 0.120

Ammonia (N) mg/L

0.100 0.080 0.060 0.040 0.020 0.000 1/ 2/

03

1/ 6/

03

29 9/

3 /0

27 1/

4 /0

26 5/

4 /0

23 9/

4 /0

21 1/

5 /0

21 5/

5 /0

18 9/

5 /0

16 1/

6 /0

16 5/

6 /0

13 9/

6 /0

11 1/

7 /0

11 5/

7 /0

8/ 9/

07

6/ 1/

08

Date BR at Diversion

BR at Glenwood

BR near Parma

BR above Middleton

Figure 36. Ammonia data collected by the USGS from Lower Boise River locations from 2003 to 2008. Lower Boise River Tributary Ammonia (N) Concentrations, 2005

Ammonia (N) mg/L

0.500 0.400 0.300 0.200 0.100 0.000 4/15/05

5/15/05

6/14/05

7/14/05

8/13/05

Date

Fivemile Ck

Tenmile Ck

Fifteenmile Ck

Willow Ck

Mason Ck

Figure 37. Ammonia data collected by the USGS from Lower Boise River tributaries, 2005.

59

Indian Ck

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Lower Boise River Drains Ammonia (N) Concentrations, 2005

Ammonia (N) mg/L

0.150

0.100

0.050

0.000 4/15/05

5/15/05

6/14/05

7/14/05

8/13/05

Date Mill Slough

Conway Gulch

Dixie Drain

Figure 38. Ammonia data collected by the USGS from Lower Boise River drains, 2005.

Indian Creek Ammonia Concentrations, AU 002_04, 2003-2007

3.3 3 2.7 2.4 2.1 1.8 1.5 1.2 0.9 0.6 0.3 0 01 /0 1/ 04 03 /0 1/ 06 03 /3 0/ 09 03 /2 8/ 12 03 /2 7/ 03 03 /2 6/ 06 04 /2 4/ 09 04 /2 2/ 12 04 /2 1/ 03 04 /2 1/ 06 05 /1 9/ 09 05 /1 7/ 12 05 /1 6/ 03 05 /1 6/ 06 06 /1 4/ 09 06 /1 2/ 12 06 /1 1/ 03 06 /1 1/ 06 07 /0 9/ 09 07 /0 7/ 12 07 /0 6/ 07

Ammonia (mg/L)

Data Collected by City of Nampa

Date Upstream

Downstream

Figure 39. Ammonia data collected by the city of Nampa upstream and downstream of the WWTP on Indian Creek, 2003-2007. Figure 39 represents another circumstance where permitted point source effluent may provide a diluting effect on pollutant loads by reducing ammonia concentrations downstream of the point of discharge. Based on data collected by the USGS, ISDA, DEQ and the city of Nampa, reported ammonia concentrations do not exceed criteria for COLD beneficial uses.

60

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Flow and Habitat Prior to westward expansion of the population of the United States, human population in the Lower Boise River subbasin was sparse. Ore mining in the region in the mid-1800s promoted rapid migration to the Boise River subbasin. Agriculture in river valleys to provide food for the mining towns completely altered the natural hydrology of the Lower Boise River subbasin by the late 1800s (ISHS, various dates). By the early 1900s, federal land management agencies had been created to develop water resource projects to control flooding and provide for irrigation needs to support agriculture in the western United States (USACE, 1995; US BOR, 1997). The results of those activities in the Lower Boise River subbasin are almost 500 miles of canals and drains and at least 49 permitted dams and numerous impoundments, diversions and drains to accommodate urban and agricultural activities (Figure 40). This does not account for or address the diversions and impoundments that are not documented or monitored or the quality and quantity of those features. All streams in the subbasin have been altered or modified and in most years 75 to 89% of the mainstem flow is diverted between Diversion Dam and the Glenwood Bridge (Figure 42), with an estimated 59% of diverted water returned to the mainstem through drains or subsurface flow between Star and Parma (BOR, 2007). Between the Glenwood Bridge and Parma additional diversions remove an additional 1,600 cfs during the peak of a typical irrigation season.

Figure 40. Lower Boise River constructed dams and diversions (canals) permitted through the Idaho Department of Water Resources (IDWR).

61

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure 41. Diagram of diversions and returns to the Lower Boise River, as adapted from Digital Atlas of Idaho, 2008. It is not possible to determine what effect diversions and drains have on water quality in the Lower Boise River subbasin because water quality data for diversions and drains is not available. It is likely that diversions and drains increase water temperature in the mainstem and it appears that the water contributed back to the mainstem by the drains is warmer than the water contributed by the tributaries. The effect of the numerous streamside impoundments is also unknown. Flows and diversions from Lucky Peak to Glenwood are represented in Figure 42, and from Glenwood to Parma in Figure 43.

Flow (cfs)

Flows and Diversions from Lucky Peak Outfall to Glenwood Bridge, 2007 5000 4500 4000 3500 3000 2500 2000 1500 1000

9/ 28 /0 7 10 /2 8/ 07 11 /2 7/ 07 12 /2 7/ 07

8/ 29 /0 7

7/ 30 /0 7

6/ 30 /0 7

5/ 1/ 07 5/ 31 /0 7

4/ 1/ 07

3/ 2/ 07

1/ 1/ 07 1/ 31 /0 7

500 0

Date Lucky Peak Outfall

Diversion Dam to Glenwood Diversion

Glenwood

Figure 42. Graph of flow and diversions reported by the USGS for the Lower Boise River between Lucky Peak Dam outfall and Glenwood Bridge, 2007.

62

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Flows and Diversions in the Lower Boise River, 2007 1800 1600 1400 Flow (cfs)

1200 1000 800 600 400 200

12 /2 7/ 07

07 10 /2 8/ 07 11 /2 7/ 07

9/ 28 /

07 8/ 29 /

07 7/ 30 /

07 6/ 30 /

5/ 31 /0 7

5/ 1/ 07

4/ 1/ 07

3/ 2/ 07

07 1/ 31 /

1/ 1/ 07

0

Date Glenwood S. Channel at Eagle

Glenwood to Parma Diversion Parma

Figure 43. Graph of flow and diversions reported by the USGS for the Lower Boise River between Glenwood Bridge and the mouth, 2007.

Summary of Beneficial Uses Based on a review of available data the most prevalent factor affecting water quality in the Lower Boise River subbasin appears to be flow and habitat alteration. While this impairment may not be necessarily remedied through the TMDL process negative effects can be mitigated through adoption of flow control practices that more closely resemble natural flow cycles. Federal water project management agencies, subbasin stakeholders and land stewards can address flow and habitat impairment through a variety of restoration projects and BMP implementation. The second most observed impairment of beneficial use attainment is bacteria, with eight AUs reporting sample results that exceed criteria. Other pollutants determined to be limiting the attainment of beneficial uses (in order of prevalence) are sediment and temperature. Sediment impairment was determined using reported water chemistry analysis of SSC and TSS samples, BURP scores and observations of tributary effluent to the Boise River. There is one AU in the Lower Boise River subbasin (AU 013_03, Dry Creek) that has been determined to be supporting all designated or presumed beneficial uses. Excursions from maximum temperature criteria were correlated with aquatic community data, where available, to determine or confirm impairment by elevated water temperatures. An evaluation of reported benthic macroinvertebrate sample data indicates the largest proportion of benthic macroinvertebrate organisms in the Boise River subbasin appear to favor warm water temperatures; with more than 80% of the identified organisms near Middleton categorized as tolerant of hot water. While Tier II data cannot be used to make use determinations, the aquatic community temperature tolerance does

63

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

correlate with the pattern of diversions and the warming of diverted water before the water is returned to the mainstem between Star and Caldwell; with water temperatures cooling in the mainstem as more flow and groundwater effluent is received by the mainstem channel downstream of Middleton. Concentrations of bacteria and sediment can be directly related to land use practices in the subbasin, with elevated concentrations of bacteria occurring more often near areas with active animal feeding operations, and sediment concentrations increasing near areas that are irrigated by gravity flow systems. These are all issues that were addressed in the TMDL implementation plan in 2003. Table 19 summarizes the results of the review of the subbasin and data collected by agencies and organizations with land management responsibilities (Table 12).

64

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Status of Beneficial Uses Current designated beneficial uses, listing status, impairments, and recommendations for the next integrated report are identified for each AU listed on the impaired waters list of the draft 2008 Integrated Report and summarized in Table 19. Table 19. Summary of assessment units, draft 2008 Integrated Report, existing TMDLs, and five-year review results. Assessment Unit (2008 draft Integrated Report) 001_02

Stream Segment Description

2008 Draft List Pollutant

Summary of Data and Observations

Unnamed 1st Temperature and 2nd order tributaries to Boise River between Indian Creek and the mouth.

Riparian area 2 and 3 from the TMDL including paleo oxbow lakes of the Boise River. Channels have been constructed to irrigate and drain cultivated fields; remnant wetlands and ponds remain.

Recommended Changes to Next Integrated Report Add to Section 3 as unassessed. Collect data to verify listed impairments. Add to Section 4c for flow and habitat alteration.

001_06

Boise River 6th order from Indian Creek to the mouth, and tributaries to the 6th order.

Temperature

Paleo meanders of the Boise River, modified by diversions and drains for agricultural uses. Diversions remove 76% of summer flow. Temperature and geomean bacteria data exceed criteria. Sediment data exceeds TMDL targets.

Add to Section 4c for flow and habitat alteration.

002_04

Indian Creek 4th order from Phyllis Canal to mouth.

Temperature, Bacteria

Data exceed TMDL targets for sediment and criteria for bacteria, and temperature. All other criteria are met.

Add to Section 5 for sediment. Schedule a TMDL for bacteria and temperature.

Confined channel and de-vegetated riparian zones in urban impact area.

Add to Section 4c for flow and habitat alteration.

North Indian Creek, 1st and 2nd order.

Sediment, Bacteria, Nutrients

Ephemeral or intermittent, channels with numerous dams.

Add to Section 3 as unassessed and collect data to determine use designation and status.

003_02

Add to Section 4c for flow and habitat alteration.

65

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit (2008 draft Integrated Report) 003_03

003a_04

005_02

Stream Segment Description

2008 Draft List Pollutant

Indian Creek 3rd order, upstream of Sand Creek.

Sediment, Temperature, Nutrients

Indian Creek 4th order from Sand Creek to Phyllis Canal. First and second order unnamed streams or tributaries to the Boise River from Glenwood Bridge to Mason Creek.

Summary of Data and Observations BOR data indicates criteria and TMDL targets are met when flow is present. BURP data indicates dry streams for 2 out of 3 sampling events. Constructed flow controls, ephemeral and intermittent streams, many impoundments.

Sediment, Temperature, Unknown, DO

Data exceed criteria for temperature. All other criteria are met.

Channelized, irrigation diversions, wastewater drains. Secondary or abandoned channels and cut- off meanders of the mainstem Boise River, modified for agricultural uses (Miller canal) or urban development. Numerous diversions and drains, two large gravel mines.

66

February 2009

Recommended Changes to Next Integrated Report De-list for sediment, temperature, nutrients.

Add to Section 4c for flow and habitat alteration. De-list for sediment, unknown and DO. Schedule a temperature TMDL. Add to Section 4c for flow and habitat alteration. Add to Section 3 as unassessed and Section 4c for flow and habitat alteration. Collect data to determine uses and water quality status.

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit (2008 draft Integrated Report) 005_06

006_02

007_02

007_04

008_02

Stream Segment Description

2008 Draft List Pollutant

Boise River 6th order, and tributaries to 6th order, from Glenwood Bridge to Mason Creek.

Temperature

Mason Creek source to mouth.

Sediment, Unknown, DO, Nutrients

February 2009

Summary of Data and Observations

Recommended Changes to Next Integrated Report

Data indicate temperature exceeds criteria; and bacteria exceeds criteria and TMDL targets. Confined channel, diversions, streamside rapid infiltration basins/impoundments, industrial activity, de-vegetated riparian zone, irrigation and industrial drains, urban development.

Data indicate sediment and bacteria exceed criteria and TMDL LAs. All other data is within criteria. Confined Channel, diversions, drains, de-vegetated riparian zone.

Add to Section 4c for flow and habitat alteration.

De-list for DO, nutrients and unknown. Add to Section 5 for sediment and bacteria. Add to Section 4c for flow and habitat alteration.

Fifteenmile Creek, 1st and 2nd order and tributaries.

Data for bacteria exceed criteria and sediment exceeds TMDL targets.

Add to Section 5 for bacteria and sediment.

Channel is constructed, or modified to appear constructed, for agricultural purposes.

Add to Section 4c for flow and habitat alteration.

Fifteenmile Creek, 4th order and tributaries to the 4th order.

Data indicate sediment and bacteria exceed criteria, and all other criteria are met.

Add to Section 5 for sediment and bacteria.

Channel is constructed, or modified to appear constructed, for agricultural purposes.

Add to Section 4c for flow and habitat alteration.

1st and 2nd order tributaries to Tenmile Creek.

Ephemeral or intermittent channels, one spring and wetland. Several dams, 14 rapid infiltration basins near industrial sites, sand/gravel mines, isolated cultivated agricultural sites.

Add to Section 4c for flow and habitat alteration.

67

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit (2008 draft Integrated Report) 008_03

Stream Segment Description Third order Tenmile Creek.

2008 Draft List Pollutant Bacteria, Unknown, Nutrients

February 2009

Summary of Data and Observations Data indicate sediment and bacteria exceed criteria, and all other criteria are met.

Numerous dams and reservoirs, and riparian modification for agriculture. 009_02

Blacks Creek 1st and 2nd order.

Habitat Alteration

Intermittent and ephemeral streams, dams and flow controls.

Recommended Changes to Next Integrated Report De-list for unknown and nutrients. Add to Section 5 for sediment. Schedule a TMDL for bacteria. Add to Section 4c for flow and habitat alteration. Add to Section 3 as unassessed. Collect data to determine existing uses and water quality status. Add to Section 4c for flow alteration.

009_03

Blacks Creek 3rd order.

Habitat Alteration

Intermittent flow, flow control structures. Removed from BOR’s management plan because of poor storage potential and flow conditions. Reservoir is managed by IDFG.

Add to Section 3 as unassessed. Collect data to identify existing uses and water quality status. Add to Section 4c for flow alteration.

010_02

Fivemile Creek 1st and 2nd order.

Bacteria

No data to support listing for bacteria. Intermittent and ephemeral channels. Stream has been modified to support canal system, parts of channel completely obscured by ag/urban development.

010_03

Fivemile Creek 3rd order.

Unknown, DO, Nutrients, Habitat Alteration

Data indicate exceedance of sediment and bacteria criteria. Channelization for ag/urban development.

68

Add to Section 3 as unassessed. Collect data to determine water quality status. Add to Section 4c for flow and habitat alteration. De-list for DO, nutrients and unknown. Add to Section 5 for sediment and bacteria. Add to Section 4c for flow alteration.

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit (2008 draft Integrated Report)

Stream Segment Description

011a_02

1st and 2nd order tributaries to Boise River from Barber Dam to Glenwood Bridge.

011a_06

Boise River from Barber Dam to Glenwood Bridge.

2008 Draft List Pollutant

February 2009

Summary of Data and Observations Ephemeral or intermittent streams, a few small springs, dams and impoundments. Remnant rapid infiltration basins on banks of Boise River. Streams are not tributaries to the river.

Temperature

1st and 2nd order streams and tributaries near outfall of Lucky Peak Dam.

011b_06

Boise River between Lucky Peak outfall and Diversion Dam.

Add to Section 4c for flow and habitat alteration.

Temperature criteria for salmonid spawning are exceeded every spring and most fall months. Criteria for pH, sediment, bacteria, DO, and ammonia are met. Flow control structures and diversions, near-stream impoundments, removal of riparian vegetation, wastewater drains. Includes Riparian area 1 from the TMDL.

011b_02

Recommended Changes to Next Integrated Report

Dams and impoundments in the headwaters and near the valley floor. The only tributary to the river is at the base of the dam and may flow in response to that structure.

Flow Alteration

Add to Section 4c for flow and habitat alteration.

Add to Section 4c for flow and habitat alteration.

Data indicate that criteria area met for temperature, pH and DO. Flow control structures, diversions and urban development have modified habitat.

69

Add to Section 4c for habitat alteration.

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit (2008 draft Integrated Report) 012_02

012_03

Stream Segment Description

2008 Draft List Pollutant

Stewart Gulch, Cottonwood and Crane Creeks, 1st and 2nd order.

Habitat Alteration

Stewart Gulch, Cottonwood and Crane Creeks, 3rd order to mouth.

Habitat Alteration

February 2009

Summary of Data and Observations Cottonwood Creek is intermittent, based on USGS recent flow records for AU 012_03.

Springs are developed and impounded, or diverted from natural channels. Flood control structures— sediment and overflow basins-- dating from the early 1900’s prevent mass wasting and reduce sediment loads to the river. Streams are modified with flood control structures and diversions. Flow is directed through pipes and flumes to the Boise River.

Recommended Changes to Next Integrated Report Add to Section 3 as unassessed. Collect data to determine existing uses and water quality status. Add to Section 4c for flow alteration.

Add to Section 3 as unassessed. Collect data to determine existing uses and water quality status. Add to Section 4c for flow alteration.

013_02

1st and 2nd order Dry Creek and tributaries.

Flow control structures and reservoirs in tributaries to Currant Creek.

Add to Section 4c for flow alteration.

013_03

3rd order Dry Creek and tributaries.

Data indicate that all criteria are met.

Add to Section 2 as supporting presumed uses.

013_04

4th order Dry Creek.

Flow control structures and channel modification to accommodate agriculture and urban development. Flow control structures, channel modification, ag/urban development, gravel mine, and numerous impoundments.

Collect data to determine existing uses and water quality status. Add to Section 4c for flow and habitat alteration.

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit (2008 draft Integrated Report) 014_02

Stream Segment Description

2008 Draft List Pollutant

February 2009

Summary of Data and Observations Flow control structures and channel modifications to accommodate agriculture.

Big/Little Gulch Creek Complex

Recommended Changes to Next Integrated Report Collect data to determine existing uses and water quality status. Add to Section 4c for flow and habitat alteration.

015_02

South Fork Willow Creek.

Habitat Alteration, Temperature

Ephemeral or intermittent streams.

Flow control structures and impoundments.

015_03

016_02

Willow Creek, North Fork Willow Creek, and unnamed tributaries. Langley/ Graveyard Gulch complex

Temperature, Habitat Alteration

Collect data to determine existing uses and water quality status. Add to Section 4c for flow alteration.

Data indicate bacteria exceeds criteria and TMDL targets, and all other criteria are met.

De-list for temperature. Add to Section 5 for bacteria.

Channelized for ag/urban development, dewatered stream segments.

Add to Section 4c for flow alteration.

Appears to drain to the Payette River subbasin.

Initiate review to determine possibility that landforms drain to HUC 17050122. Collect data to determine existing uses and water quality status.

Flow control structures and channel modification to accommodate agriculture.

71

Add to Section 4c for flow and habitat alteration.

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit (2008 draft Integrated Report) 016_03

Stream Segment Description Langley/ Graveyard Gulch complex

2008 Draft List Pollutant Sediment, Unknown, Nutrients, DO

February 2009

Summary of Data and Observations Most streams are ephemeral, 3 or 4 springs, no defined natural stream channels. No data to support listing.

Constructed and modified channels to accommodate agriculture. 017_02

017_03

017_06

Recommended Changes to Next Integrated Report Add to Section 3 as unassessed. Collect data to determine existing uses and water quality status. Add to Section 4c for flow and habitat alteration.

Data indicate all criteria are met.

1st and 2nd order Sand Hollow Creek and tributaries.

Constructed and modified channels to accommodate agriculture.

Add to Section 4c for flow and habitat alteration.

Sand Hollow Creek 3rd order and tributaries

Sediment, Unknown, DO

Data indicate sediment exceeds TMDL targets. All other criteria are met.

De-list for DO and unknown. Schedule a sediment TMDL.

All streams are modified to facilitate agriculture.

Add to Section 4c for flow and habitat alteration.

Sand Hollow Creek

Sediment, Nutrients, DO, Unknown

Data indicate that bacteria exceed criteria and sediment exceeds TMDL targets and criteria.

Add to Section 5 for sediment and bacteria.

Channelized, flow control structures, impoundments, diversions, and irrigation drains.

Add to Section 4c for flow and habitat alteration.

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Summary of Recommendations Because the draft 2008 Integrated Report was not approved before development of this review, the final 2008 Integrated Report may not reflect recommendations made in this report. All recommendations for the next Integrated Report refer to the 2010 Integrated Report. The following paragraphs are brief explanations of the recommendations summarized in Table B. Because all of the AUs discussed in this review are in the Lower Boise River subbasin, (HUC 17050114) the AUs will be referred to by the numerical suffix assigned to each AU in Idaho’s WQS. For example, the AU identified in Idaho WQS as ID17050114SW001_02 is abbreviated to 001_02. The following paragraphs are brief explanations of the beneficial use attainment status of each AU and the rationale used in offering recommendations for the next integrated report. Designated beneficial, existing, and presumed uses; WQS; and criteria for each AU are defined and summarized in Section 3 of this document. Some AUs received LAs in the TMDL because it was determined that the AU may be contributing, in a cumulative manner, to impairment of the stream segment of concern to the TMDL. An LA is not equivalent to a listing of impairment. 001_02 This AU includes 2 unnamed 1st order tributaries to the Boise River between Indian Creek and the mouth (including Riparian Area 2 and 3 of the TMDL) and is in Section 5 of the draft 2008 303(d) list for temperature. Beneficial uses are not designated and are presumed to meet cold water aquatic life (COLD) and primary and secondary contact recreation (PCR/SCR) uses. A review of satellite photo images from 2006 indicate that this AU is primarily remnant channels and oxbows of the Boise River that have been modified to irrigate and drain agricultural lands surrounding a large wetland. No temperature data is available to verify the listing in the draft 2008 Integrated Report. This AU should be added to Section 3 as unassessed and listed in Section 4c for flow and habitat alteration. Data should be collected to determine appropriate use designation and water quality status. 001_06 This AU includes the Boise River 6th order segment from Indian Creek to the mouth and unnamed tributaries to the 6th order segment. The designated uses for this AU are COLD and PCR and it is listed in the draft 2008 Integrated Report for temperature and has approved TMDLs for sediment and bacteria (DEQ, 1999). There are four control monitoring locations for the TMDL in this AU. Data has been collected from three of these locations in the past five years. The WQS for PCR have changed since the TMDLs were developed to an E. coli-based standard for bacteria. Water District 63 controls flows through diversions and drains. Diversions total 1,600 cfs (76%) in an average July and drains are not monitored. Numerous canals and drains have been constructed and urbanization has resulted in modified channels throughout the AU. 73

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

The U.S. Geological Survey (USGS) and the City of Boise have collected water quality data over the past five years that indicate the temperature of the Boise River in this AU exceeds criteria and geomean bacteria results exceed criteria. Two drains have been monitored for water quality: Dixie Drain and Conway Gulch. Data from these drains indicate temperature, sediment, and instantaneous bacteria criteria are exceeded; and phosphorus concentrations may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. Conway Gulch contributes more sediment and phosphorus than Dixie Drain and Dixie Drain contributes more bacteria than Conway Gulch. Sediment and bacteria LA targets established in the TMDL (DEQ, 1999) have not been achieved in this AU. This AU should be listed in Section 4c of the next Integrated Report for flow and habitat alteration. 002_04 This AU includes Indian Creek 4th order from Phyllis Canal to the mouth, Caldwell Highline Canal and Notus Canal. The designated uses are COLD and SCR and the AU is listed as impaired by temperature and bacteria in the draft 2008 Integrated Report. There is one control monitoring location in this AU for the TMDL and an LA for bacteria and sediment at the confluence with the Boise River. The WQS for SCR have changed since the TMDLs were developed, to an E. coli-based standard for bacteria. The stream has been straightened and confined and the riparian zone has been devegetated through the urban area. Agricultural drains and industrial and municipal effluent contribute to streamflow in this AU. The USGS and the Idaho State Department of Agriculture (ISDA) have collected water quality data from the control monitoring location over the past five years and reported results indicate that instantaneous bacteria and sediment criteria and TMDL targets are exceeded in this AU. There are also sediment plumes from the confluence into the Boise River visible in satellite images. Phosphorus data indicate that concentrations may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. Dissolved oxygen (DO) and pH are within criteria. The city of Nampa collected data above and below the WWTP from 2003 through 2007 in compliance with permit requirements. The data indicate that sediment, DO and pH are within criteria at the WWTP. Temperature criteria is exceeded in summer and fall months upstream of the WWTP. Because the temperature data collected by the USGS in 2005 was always collected in the morning and there are only 5 data points in that dataset, the data from the City of Nampa was more useful in making a determination for temperature in this AU. This AU should be listed in Section 5 for sediment, listed in Section 4c for flow and habitat alteration and a TMDL for bacteria and temperature should be scheduled.

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

003_02 This AU includes North Indian Creek and 1st and 2nd order streams and tributaries. Slater Creek, Cow Creek, Sheep Creek, Ridenbaugh Canal, North Indian Creek, West Fork Slater Creek, Sand Creek and East Fork Slater Creek are in this AU. Beneficial uses are not designated and are presumed to meet COLD and PCR/SCR uses. The AU is listed in the 2008 draft Integrated Report for sediment, bacteria and nutrients. There is no evidence of anything more than ephemeral flow east of Pleasant Valley Road, in Ada County. Some evidence of intermittent flow is present between Pleasant Valley Road and South Cole Road, in Ada County. There are three flow control structures in Caldwell Draw and one in Slater Creek. East of South Cole Road, North Indian Creek is impounded, with no observed flow below the dam. There is no evidence of flow in the channel west of the impoundment until Cloverdale Road, where another large impoundment has been constructed in the stream channel just south of Kuna-Mora Road, on the east side of Cloverdale Road. North of Kuna-Mora Road the channel of North Indian Creek has been obliterated by cultivated fields, and meander scars are still visible in satellite images. Several impoundments have been constructed throughout the AU, and very little water is visible in the basins. Water quality data is not available for this AU and attempts to collect BURP data in 2007 failed due to dry stream conditions. Based on a review of available data, it is recommended that this AU be scheduled for a thorough assessment of existing conditions to determine correct designation of beneficial uses and water quality status. This AU should be listed in Section 3 as unassessed and Section 4c for flow and habitat alteration in the next Integrated Report. 003_03 This AU includes the 3rd order of Indian Creek, upstream of Sand Creek (including Indian Creek Reservoir), 3rd order of North Indian Creek, Sand Creek and unnamed tributaries. Indian Creek Reservoir was constructed before the existence of federal land management agencies and is managed by the Idaho Department of Fish and Game (IDFG) as a warm water fishery. The designated uses of this AU are COLD and SCR and it is listed in the draft 2008 Integrated Report for sediment, temperature and nutrients. Some unnamed streams, and possibly a portion of Indian and North Indian Creek, may be intermittent. In addition to numerous small impoundments on Indian Creek, there are three dams and two impoundments in Caldwell Draw (between Sheep and Indian Creeks) and one in Sheep Creek that appear to capture all available surface water. The IDFG frequently promotes salvage fishing from Indian Creek Reservoir in dry years and waits until a relatively wet year to restock the reservoir. The reservoir was classified by the IDFG as “dry” from 2001 through 2006. In 1999, the Bureau of Reclamation (BOR) collected water quality data from the inlet of the reservoir and from Indian Creek above the confluence with the New York Canal.

75

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

BOR data indicate that criteria and TMDL targets for the Lower Boise TMDL are met at the sample locations when flow is present. While the data is too old to be used for use determination in accordance with WBAG II (Grafe, et al., 2002), it can be used as Tier II data. It is recommended that this AU be de-listed for sediment, temperature and nutrients, assessed for use modification to MOD (not yet approved by EPA) and SCR and listed in Section 4c of the next Integrated Report for flow alteration. 003a_04 This AU includes Indian Creek 4th order from Sand Creek to Phyllis Canal and tributaries to the 4th order segment. The designated uses of this AU are COLD, salmonid spawning (SS) and SCR, and it is listed in the draft 2008 Integrated Report for sediment, temperature, DO and unknown. Sand and North Indian Creeks and unnamed tributaries appear to be ephemeral streams. Some unnamed streams, and possibly a portion of North Indian Creek, may be intermittent. There is a dam and a reservoir at the confluence of Sand and Indian Creeks and numerous channel modifications and impoundments in Indian Creek downstream of Sand Creek. DEQ collected BURP data (including fish and macroinvertebrate data) from this AU in 2003 that resulted in a low score and a determination that aquatic life beneficial uses are not supported in this AU (BURP Site ID 2003SBOIA051). DEQ also collected data in 2008 which indicate that water temperature in the spring exceeds criteria and one E. coli sample exceeded the single sample criteria, but no geomean data has been collected. All other data are within criteria. This AU should be de-listed for sediment, DO and unknown; scheduled for a temperature TMDL and listed in Section 4c for flow and habitat alteration in the next Integrated Report. 005_02 This AU includes the 1st and 2nd order unnamed streams or tributaries to the Boise River from Glenwood Bridge to Mason Creek, and the Miller canal. The beneficial uses are not designated and are presumed to support COLD and SCR/PCR uses. The AU is listed in the draft 2008 Integrated Report as unassessed. There is no water quality data for this AU and a review of satellite images indicates that these streams are secondary or abandoned channels and cut-off meanders of the mainstem Boise River that have been modified for agricultural uses or urban development. There are numerous diversions and drains and two large gravel mines in this AU and the land uses are cultivated agriculture, industrial and suburban. This AU should be added to Section 3 as unassessed, listed in Section 4c of the next Integrated Report for flow and habitat alteration and should be assessed to determine appropriate beneficial use designation and water quality status.

76

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

005_06 This AU includes Boise River 6th order, from Glenwood Bridge to Mason Creek and unnamed tributaries to the 6th order mainstem river, including the Phyllis Canal. The designated uses of this AU are COLD, SS and PCR and it is listed in the draft 2008 Integrated Report as impaired by temperature. The mainstem river in this AU has approved TMDLs for sediment and bacteria. There are 10 TMDL control monitoring locations in this AU and data has been collected from five of these in the past five years. Discharge (flow volume), suspended sediment and bacteria data have been collected from two control monitoring locations by the USGS and ISDA between 2003 and 2008. The implementation plan specified plans for geomean bacteria data to be collected at control monitoring locations to determine compliance with the TMDL and geomean data was collected by the city of Boise in 2005. In addition to the constituents monitored for existing TMDLs, the city of Boise has collected continuous temperature data from the Boise River control monitoring location from 2003 to 2008. The perennial streams in this AU have been modified to facilitate agricultural activities with numerous diversions and drains and urban development has encroached into the floodplain of the mainstem river and has fostered devegetation of riparian zones along deepened and channelized streams. Between Glenwood Bridge and Parma, 76 to 89% of the flow is diverted every irrigation season, with an estimated 50% of that flow returning to the mainstem river between Star and Caldwell (BOR, 2008). Results of data collection reported by the USGS and the City of Boise indicate that geomean bacteria criteria are exceeded in the Boise River above Middleton and near Caldwell. Single-sample (instantaneous) bacteria criteria are exceeded in Mill Slough, but no geomean samples have been collected. Temperature data reported by all data collection agencies indicate that temperature criteria for SS are exceeded in the mainstem Boise River above Middleton every spring, and some years in the fall months. This pattern is evident from data collected at Mill Slough also. This AU should be listed in Section 4c of the next Integrated Report for flow and habitat alteration. 006_02 This AU includes Mason Creek from source to mouth, including Kuna Canal, New York Canal, Mason Slough and Mason Creek Feeder. It is designated for beneficial uses of MOD (not yet approved by EPA) and SCR and is listed in the draft 2008 Integrated Report for sediment, unknown and DO. This AU has LAs and two control monitoring locations for sediment and bacteria in the TMDL, at the confluence with the Boise River. The stream channel is visibly confined with numerous diversions and drains and the riparian zone has been de-vegetated to allow for urban development. The USGS and ISDA have collected data from one TMDL control location between 2003 and 2008 and DEQ collected BURP data from this AU in 2003 (BURP Site ID 2003SBOIA050). Based on the sample results reported by the data collection agencies, sediment and bacteria exceed criteria and TMDL targets. Reported values of DO and

77

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

temperature are within criteria. The BURP scores, which include fish and macroinvertebrate data, were low and resulted in a determination that aquatic life and recreation beneficial uses are not supported in this AU. In the next Integrated Report, this AU should be de-listed for DO and nutrients, listed in Section 5 for bacteria and sediment and listed in Section 4c for flow and habitat alteration. 007_02 This AU includes the first and second order unnamed streams in the Fifteenmile Creek watershed. Beneficial uses are not designated and are presumed to meet COLD and SCR/PCR uses. The AU is listed in the draft 2008 Integrated Report as unassessed. This AU begins at the confluence of Tenmile and Fivemile Creeks, near the intersection of Linder and Franklin roads in Ada County and parallels the Highline Canal. The ISDA collected water quality data from this AU in 2008 and Tenmile and Fivemile Creeks are listed in the draft 2008 Integrated Report as impaired for bacteria and nutrients. This stream is a constructed channel or has been modified by agriculture and urban activities so that it appears to be entirely constructed. Results of data collected by the ISDA indicate that single-sample (instantaneous) bacteria criteria are exceeded more than 50% of the time, but no geomean samples have been collected. Results of suspended sediment analyses indicate that short-term and long-term TMDL targets are exceeded in this AU and criteria appear to be exceeded. Phosphorus concentrations may exceed recommended concentrations of 0.07 mg/L (Snake RiverHells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. All other criteria appear to be met. Based on the information reviewed for this report, this AU should be listed in Section 5 for sediment and bacteria and Section 4c of the next Integrated Report for flow and habitat alteration. This AU should also be assessed for appropriate designation of uses. 007_04 This AU includes the 4th order of Fifteenmile Creek and unnamed tributaries. It is designated for beneficial uses of MOD (not yet approved by EPA) and SCR and is listed in the draft 2008 Integrated Report as unassessed. LAs for sediment and bacteria were assigned to one location in this AU with one control monitoring location. Water quality data is available for this AU and Tenmile and Fivemile Creeks (headwater source) are listed in the draft 2008 Integrated Report as impaired for bacteria and nutrients. This stream is a constructed channel or has been modified by agriculture and urban activities so that it appears to be entirely constructed. There are at least four diversions and numerous drains in this AU, which are used for agricultural purposes. Water quality data collected by the USGS in the summer of 2005 indicate that bacteria concentrations exceed the single-sample criteria, but geomean data has not been collected. All samples

78

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

collected exceed the TMDL 60-day maximum target for suspended sediment, and phosphorus concentrations may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. All other reported values (temperature, pH and DO) are within standards. Based on information reviewed for this report, this AU should be listed in Section 5 for bacteria and sediment, and in Section 4c for flow and habitat alteration, in the next Integrated Report. 008_02 This AU includes 1st and 2nd order streams in the Tenmile Creek watershed. The beneficial uses are not designated and are presumed to be COLD and PCR/SCR. It is listed in the draft 2008 Integrated Report as unassessed. There is no water quality data for this AU but a review of satellite images indicates that most of the streams are ephemeral or intermittent, with the exception of one spring and wetland. There are several dams that appear to have dry or nearly dry impoundments, 14 rapid infiltration basins near industrial sites and at least nine sand/gravel mines. There are a few isolated cultivated agricultural sites. This AU should be listed in Section 4c of the next Integrated Report for flow and habitat alteration and data should be collected to determine the appropriate beneficial use designation and water quality status. 008_03 This AU includes the third order of Tenmile Creek, downstream of Blacks Creek Reservoir. It is designated for beneficial uses of MOD (not yet approved by EPA) and SCR and is listed in the draft 2008 Integrated Report for bacteria, nutrients and unknown. LAs for sediment and bacteria at the mouth of Tenmile Creek were established in the TMDL. There are numerous dams and impoundments and the riparian zone has been modified for agricultural uses. Data has been collected by the USGS four times between 2003 and 2008. Based on reported results, Tenmile Creek exceeds single-sample bacteria criteria and TMDL targets for sediment. Data to calculate bacteria geomean values has not been collected. Phosphorus concentrations may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. No other impairments are documented. It is recommended that this AU be de-listed for unknown and nutrients, listed in Section 5 for sediment and in Section 4c of the next Integrated Report for flow and habitat alteration. A bacteria TMDL should be scheduled.

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

009_02 This AU includes Blacks Creek 1st and 2nd order streams to the reservoir, Bryans Run and unnamed tributaries, and is listed in the draft 2008 Integrated Report for habitat alteration. Beneficial uses are not designated and the AU is presumed to meet COLD and PCR/SCR uses. A review of satellite images indicates that most of this AU is intermittent or ephemeral, with three pools in the main channel of Blacks Creek, but no flowing water. Bryans Run contains two constructed flow control features and three unnamed tributaries have constructed impoundments, but no free-flowing water. Water quality data has not been collected from this AU in the past five years, and BURP samples from 1996 (1996SBOIA055) and 1998 (1998SBOIA006) indicate that dry stream conditions dominate this AU in the spring and summer months. This AU should be added to Section 3 as unassessed and listed in Section 4c for flow and habitat modification in the next Integrated Report. Data should be collected to determine appropriate beneficial use designation and water quality status. 009_03 This AU includes Blacks Creek 3rd order, which encompasses Blacks Creek Reservoir to the headwaters of Tenmile Creek. The AU is not designated and is presumed to meet beneficial uses of COLD and PCR/SCR. It is listed in the draft 2008 Integrated Report for habitat alteration. There are three dams and impoundments in this AU and flow appears to be ephemeral in most years and intermittent in years with above average precipitation. Blacks Creek Reservoir is fed by ground water and is owned by the Bureau of Land Management (BLM) and private parties and managed by IDFG. The IDFG has designated the area as an important bird area (IBA) and is working with the BLM Four Rivers Field Office and the Land Trust of Treasure Valley to recover and restore the ecology of the watershed. The watershed has been damaged by unregulated recreation use, which has resulted in refuse dumping, avian poaching, destructive offroad vehicle use, over-grazing, housing developments and invasive weeds. Water quality data has not been collected from this AU in the past five years and BURP data collected in 1998 (1998SBOIB005) reports conditions common to intermittent waters. Data should be collected to determine appropriate beneficial use designation and water quality status. This AU should be added to Section 3 as unassessed and listed in Section 4c for flow and habitat modification in the next Integrated Report. 010_02 This AU includes 1st and 2nd order Fivemile Creek, Eightmile Creek and unnamed tributaries and is intersected by Interstate 84 southeast of the city of Boise. Beneficial uses are not designated and are presumed to be COLD and PCR/SCR. The AU is listed in the draft 2008 Integrated Report for bacteria.

80

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Water quality data has not been collected from this AU since BURP surveys documented dry stream conditions in 1998 (1998SBOIB007). Satellite images indicate that except for one or two small springs, the streams are ephemeral and may flow intermittently to West Gowen Road, where Fivemile Creek intersects the New York Canal. West of the New York Canal, the stream channel flows during the irrigation season through a mix of urban and suburban private land parcels. The stream has been straightened and deepened to support the intricate subbasin canal system. There is no riparian vegetation in this AU and it is uncertain what the natural channel morphology may have been, absent the extensive modifications now present. Agriculture and urban development of the cities of Boise and Meridian have almost completely obscured the natural stream channels throughout the remainder of the AU, which ends near the intersection of Overland and S. Eagle roads in Ada County. Data should be collected from this AU to determine appropriate use designation and water quality status. This AU should be added to Section 3 as unassessed and listed in Section 4c for flow and habitat modification in the next Integrated Report. 010_03 This AU includes the 3rd order of Fivemile Creek, which is a brief stream segment from the confluence of Eightmile Creek to the confluence with Fifteenmile Creek. The designated beneficial uses of this AU are MOD (not yet approved by EPA) and SCR and it is listed in the draft 2008 Integrated Report for habitat alteration, DO and unknown pollutants. LAs for sediment and bacteria at the mouth of Fivemile Creek were established in the TMDL, but this stream was not listed as impaired when the TMDL was developed. DEQ collected BURP data in 2003 (2003SBOIA052) that resulted in a low score and a determination of non-support of beneficial uses. The stream was dry when BURP sampling was attempted in 2005 (2005SBOIP009) and 1996 (1996SBOIA042). The USGS collected water quality data in the summer of 2005 that indicate that Fivemile Creek exceeds single-sample bacteria criteria and TMDL targets for sediment. Geomean bacteria data has not been collected. Reported results of phosphorus concentrations may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. Data collected over the same time period indicate that Fivemile Creek does not exceed criteria for temperature, DO, or pH. The same alterations to the channel and riparian habitat that were discussed for AU 010_02 are evident in this AU. This AU should be de-listed for DO and unknown pollutants and listed in Section 5 for sediment and bacteria, and Section 4c for flow and habitat modification in the next Integrated Report.

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

011a_02 This AU includes Squaw Creek, Warm Springs Creek, Maynard Gulch and unnamed 1st and 2nd order streams north of the Boise River near Barber, Idaho. The beneficial uses are not designated and are presumed to be COLD and PCR/SCR. The AU is listed in the draft 2008 Integrated Report as unassessed. Water quality data has not been collected from this AU and satellite images indicate that except for a few small springs, the streams are ephemeral or intermittent. In drainages that appear to experience some surface water flow, there are three dams and impoundments near the valley floor. These structures function as flood control structures to prevent mass wasting in the foothills from delivering excessive sediment to the Boise River. There are remnant rapid infiltration basins on the banks of the Boise River. This AU should be listed in Section 4c of the next Integrated Report for flow and habitat alteration and data should be collected to determine the appropriate designated beneficial uses and water quality status. 011a_06 This AU includes the Boise River from Barber Dam to Glenwood Bridge, including Phyllis Canal and Riparian Area 1 in the TMDL. The designated beneficial uses of this AU are COLD, SS, PCR, domestic water supply (DWS) and special resources water (SRW), and it is listed in the draft 2008 Integrated Report for temperature. The TMDL established WLAs for sediment and bacteria at each point source, and LAs for bacteria at the control monitoring location at Glenwood Bridge (USGS site 13206000). The USGS collected instantaneous discharge data at three locations from 2003 through 2008, and during the same time period the city of Boise collected continuous water temperature and geomean bacteria data from three locations: Boise River at Glenwood Bridge, Boise River at Marden Bridge and Boise River at Veterans Parkway. Data collected at Glenwood Bridge indicate that sediment and bacteria targets were not exceeded between 2003 and 2008. Fish data from 2003 indicates that SS is an existing use in this AU. Temperature data indicate that criteria for SS are exceeded most years from May through July and again in October and November at all three locations monitored by the city of Boise. Instantaneous temperature data collected by the USGS indicate that criteria exceedance is an issue from May through July. The USGS collected benthic macroinvertebrate data at the control monitoring location, but not during the time of year that can be used to determine use attainment status. DO and ammonia concentrations were within criteria for all samples and the pH criterion was exceeded once between 2003 and 2008. Phosphorus data from this AU may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. Flow and habitat in this AU have been modified by dams, reservoirs, diversions, urban encroachment in the riparian zone and point and nonpoint source effluent. Water District

82

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

63 is responsible for managing diversions in the Boise River and in most years, 76 to 85% of the flow between Barber Dam and Glenwood Bridge is diverted from the mainstem (BOR, 2008). The TMDL targets for sediment and bacteria appear to be achieved in this AU. This AU should be listed in Section 4c for habitat and flow alteration in the next Integrated Report. 011b_02 This AU includes 1st order unnamed tributaries to the Boise River below Lucky Peak Dam outfall. The beneficial uses for this AU are not designated and are presumed to support COLD and PCR/SCR uses. The AU is listed in the draft 2008 Integrated Report as unassessed. Water quality data has not been collected from this AU and satellite images indicate that except for a few small springs, the streams are ephemeral or intermittent. In drainages that appear to experience some surface water flow, there are dams and impoundments in the headwaters and near the valley floor. The only tributary to the river is at the base of Lucky Peak Dam and may flow in response to that structure. Data should be collected from this AU to determine appropriate use designation and water quality status. This AU should be listed in Section 4c of the next Integrated Report for flow and habitat alteration. 011b_06 This AU includes the Boise River between Lucky Peak Dam outfall and Diversion Dam and the tributaries to this segment of the mainstem river. The designated beneficial uses for this AU are COLD, PCR, DWS, and SRW and it is listed in the draft 2008 Integrated Report as unassessed and impaired by flow alteration. Flows are controlled by the Army Corps of Engineers (ACOE) in accordance with contracts negotiated by the Bureau of Reclamation. Water quality data has been collected by the USGS from one location between 2003 and 2008. The TMDL targets for sediment and bacteria appear to be met, based on data collected from the Boise River at Diversion Dam. The city of Boise collected continuous temperature data from below the Lucky Peak Dam outfall and the USGS collected flow data from the same location and instantaneous water temperature from the Boise River near Diversion Dam. The data indicate that temperature, DO, and pH criteria are met in this AU. Ammonia, phosphorus and aquatic life data have not been collected. It is recommended this AU be de-listed for temperature and be listed in Section 4c of the next Integrated Report for habitat alteration. 012_02 This AU includes 1st and 2nd order streams (Stewart Gulch, Hulls Gulch; Fivemile, Picket Pin, Freestone, Crane, Warm Springs and Cottonwood Creeks) on the north side of

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the Boise River between AU 011b_02 and the Glenwood Bridge. This AU does not have designated uses and is presumed to meet the beneficial uses of COLD and PCR/SCR. It is listed in the draft 2008 Integrated Report for habitat alteration. Water quality data has not been collected from the AU since 1996, when BURP data was collected from Cottonwood Creek (BURP Site IDs 1996SBOIA015 and 1996SBOIB033). Water flow was so low (0.4 cfs) during the BURP surveys that data collection was annotated as incomplete. A survey of satellite images of the watershed indicates that most of the streams in this AU are intermittent, and there are a few springs and a couple of gravel/sand mines. Several watersheds have been developed for golf courses and subdivisions and all drainages have been either truncated or straightened and diverted south of Hill Road in the city of Boise. The city of Boise has installed several flood management structures in Cottonwood Creek, Hulls Gulch, Crane Creek and Stewart Gulch to prevent mass wasting, control flooding and reduce sediment loads into the Boise River. There are sediment and overflow basins in the foothills and pipes and flumes in the floodplain that route streamflow to the river. These structures date to the early 1900s through the 1990s and are maintained by the city on a regular basis (personal communication with J. Wiley, city of Boise, 2008). Data should be collected from this AU to determine appropriate beneficial use designation and water quality status. This AU should be listed in Section 3 as unassessed and in Section 4c for flow alteration of the next Integrated Report. 012_03 This AU includes 3rd order Cottonwood Creek (from Fivemile Creek to the mouth), tributaries to Cottonwood Creek, Farmers Union Canal and tributaries to the Boise River in the Cottonwood Creek watershed. Beneficial uses are not designated and are presumed to be COLD and PCR/SCR. The AU is listed in the draft 2008 Integrated Report for habitat alteration. Most of the streams in this watershed have been modified with flood control structures as described for AU 012_02 and flow through impoundments and pipes between the foothills and the river. BURP data was last collected in 1996 by DEQ (BURP Site ID 1996SBOIA014) and flow data has been collected by the USGS from 2002 to 2008. Flow data, and information from the city of Boise Public Works Department (J. Wiley, personal communication, 2008) confirms that Cottonwood Creek is intermittent, with flow occurring November through May in most years. This AU should be assessed in accordance with the WBAG II (Grafe, et. al., 2002) to determine appropriate use designation and water quality status. This AU should be listed in Section 3 as unassessed and in Section 4c for flow alteration in the next Integrated Report.

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013_02 This AU includes 1st and 2nd order Dry Creek and tributaries. Shingle Creek, Currant Creek, Spring Valley Creek, Custer Creek, North Fork Daniels Creek, McFarland Creek, South Fork Daniels and Daniels Creek. Beneficial uses are not designated and presumed uses are COLD and PCR/ SCR. The AU is listed in the draft 2008 Integrated Report as unassessed. Water quality data has not been collected from this AU, but a survey of satellite images indicate that there are at least 12 dams and reservoirs/impoundments (most of them in Currant Creek) and the land use around most of the observable springs is residential. This AU should be assessed to determine appropriate beneficial use designation and water quality status and listed in Section 4c for flow and habitat alteration in the next Integrated Report. 013_03 This AU includes Dry Creek 3rd order and tributaries, from Daniel Creek to the confluence with Spring Valley Creek, including Currant Creek and Spring Valley Creek. The beneficial uses are not designated and are presumed to be COLD and PCR/ SCR. The AU is listed in the draft 2008 Integrated Report as unassessed. Based on a review of satellite images, most of the streams in this AU appear to be intermittent. Dry Creek and Spring Valley Creek appear to be perennial streams with irrigated cultivated fields filling the floodplain of both streams. The perennial streams appear to be confined and may have been deepened to facilitate agricultural land uses. The ISDA collected data this year (2008) and data indicate that the presumed beneficial uses are met. This AU should be added to Section 2, as supporting presumed uses, in the next Integrated Report. 013_04 This AU includes Dry Creek 4th order, and tributaries, from Spring Valley Creek to the confluence with the Boise River. The beneficial uses are not designated and are presumed to be COLD and PCR/ SCR. The AU is listed in the draft 2008 Integrated Report as unassessed. The watershed is sparsely populated, but almost all of the agriculture that requires irrigation occurs on the banks of the streams. A large gravel mine and numerous impoundments exist in the watershed. Close to the confluence with the Boise River. The city of Eagle has expanded and suburban neighborhoods almost fill the southeast half of the watershed with numerous canals and laterals transecting the perennial streams at several locations. Streams in the AU have been channelized to facilitate urban, agricultural, and industrial development. This AU should be assessed to determine appropriate beneficial use designation and water quality status and listed in Section 4c for habitat and flow alteration in the next Integrated Report.

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014-02 This AU includes Big Gulch and Little Gulch Creeks, a complex of intermittent streams, and is listed in the draft 2008 Integrated Report as unassessed. Beneficial uses are not designated and are presumed to meet COLD and PCR/SCR uses. Water quality data has not been collected from this AU and a review of satellite images indicate that the streams are ephemeral or intermittent and have been modified by flow control structures. Big Gulch Creek and Woods Gulch each have two dams and reservoirs and one dam is in Little Gulch Creek. This AU should be assessed to determine appropriate beneficial use designation and water quality status and listed in Section 4c for flow and habitat alteration in the next Integrated Report. 015_02 This AU includes 1st and 2nd order Willow Creek and tributaries. This includes Alkali, Schiller, North and South Fork Willow and Willow Creeks and Middleton Mill Ditch. The beneficial uses are not designated and are presumed to be COLD and PCR/SCR. The AU is listed in the draft 2008 Integrated Report for habitat alteration and temperature impairment. The streams in the AU appear to have ephemeral, hyporheic, or intermittent flow patterns and there is a history of frequent wildland fires. The ISDA has collected water quality data from this AU and BURP data was collected by DEQ in 1996 (1996SBOIA084), 2004 (2004SBOIAA004) and 2005 (2005SBOIA012). Attempts to conduct BURP surveys failed in 1996 because the stream channel was dry, failed in 2004 because access was denied by the landowner (who claimed the stream is always dry) and failed in 2005 because no streambed was visible and urban development was occurring at the sample location. Data collected by the ISDA is too old to be used to determine use attainment status, but indicates that the mainstem of Willow Creek in this AU is usually dry. North and South Fork Willow and Schiller Creeks have been modified by flow control structures and visibly straightened near cultivated fields. Three dams and impoundments are in the North Fork Willow Creek, two in Schiller Creek, and one in South Fork Willow Creek. This AU should be assessed to determine appropriate beneficial use designation and water quality status, listed in Section 3 as unassessed and listed in Section 4c for flow alteration in the next Integrated Report. 015_03 This AU includes the 3rd order of Willow Creek, North Fork Willow Creek and tributaries. The beneficial uses are not designated and are presumed to be COLD and

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PCR/SCR. The AU is listed in the draft 2008 Integrated Report for habitat alteration and temperature. This AU was assigned LAs for sediment and bacteria in the Lower Boise River TMDL and has one control monitoring location. A spring complex west of the junction of Pearl and Chaparral roads is visible from satellite images and the mainstem of Willow Creek has been relocated, straightened, and constricted west of the natural channel to accommodate cultivated agriculture. Riparian vegetation density increases and a braided channel reforms downstream of the irrigated fields and springs. Near Highway 16, the mainstem of Willow Creek has been straightened, confined, and possibly deepened to allow for agriculture and low-density suburban development. The stream channel appears to be dry in most places upstream of the intersection with the C-Line Canal, west of Blessinger Lane in Canyon County. Downstream of the canal, the stream channel appears to be one-third the width of the canal and riparian vegetation density varies from substantial to absent through the city of Middleton to the confluence with the Boise River, near Wiffin Lane. BURP data was collected in 1996 (1996SBOIA083, 1996SBOIA083) which resulted in documentation of a dry stream at the first site and a failing score at the second site. ISDA collected water quality data from this AU in 2008 and the USGS collected data in the summer of 2005 at the LA control monitoring location. Reported sample results indicate that this AU exceeds sediment targets and instantaneous bacteria criteria (geomean data has not been collected), and phosphorus concentrations may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. All other criteria are met. This AU should be de-listed for temperature and listed in Section 5 for bacteria, and Section 4c of the next Integrated Report for flow alteration. 016_02 This AU includes the Langley/ Graveyard Gulch complex, including the C-Line Canal West, and is listed in the 2008 draft Integrated Report as unassessed. Beneficial uses are not designated and are presumed to meet COLD and PCR/SCR uses. Most of the AU is in Gem County and the primary water bodies are constructed canals delivering water from the Payette River to this portion of the Lower Boise River subbasin. Water quality data has not been collected from this AU and a review of satellite images indicate that most natural stream channels in the AU are ephemeral in nature and most of the topography is actively cultivated. Features that resemble springs are evident in satellite images, but may be seeps from the canal system. This AU may actually contribute to the drainage area of the Payette River subbasin (17050122). Data should be collected to determine appropriate beneficial use designation and water quality status and this AU should be reviewed to determine correct HUC designation and listed in Section 4c of the next Integrated Report for flow and habitat alteration.

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016_03 This AU includes Langley and Graveyard Gulch, ephemeral streams, and several springs north of the Sand Hollow Creek watershed (AU 017). The beneficial uses are not designated and are presumed to be COLD and PCR/SCR. The AU is listed in the draft 2008 Integrated Report for sediment, nutrients, DO and unknown pollutants. All visible natural drainages are either cultivated or channeled and diverted to support cultivation. Most springs have been developed and impounded and are not connected to other surface water bodies. Numerous constructed channels deliver water from the Payette River to irrigated crops and drain used water into AU 017. Water quality data has not been collected from this AU. Data should be collected to determine appropriate use designation and water quality status and this AU should be added to Section 3 as unassessed and listed in Section 4c of the next Integrated Report for flow and habitat alteration. 017_02 This AU includes 1st and 2nd order streams in the Sand Hollow Creek watershed. This includes the D-Line Canal, Notus Canal and Farmers Cooperative Sebree Canal. The beneficial uses are not designated and are presumed to be COLD and PCR/SCR. The AU is listed in the draft 2008 Integrated Report as unassessed. This stream is a tributary to the Snake River, but is located in the Lower Boise River subbasin. It was not included in the TMDL and does not have LAs or targets for any pollutants. The largest water bodies are constructed canals and drains. Some natural channel remnant features are visible on satellite images, but most have been obliterated by cultivation and the ones that remain have been modified to facilitate agricultural practices. DEQ collected BURP data in 1996 (1996SBOIA081) and water quality data in 2008. Reported results indicate DO, bacteria, sediment, and temperature are within criteria. It is recommended that this AU be listed in Section 4c flow and habitat alteration. 017_03 This AU includes Sand Hollow Creek 3rd order, from the intersection of Farmway and Oasis roads in Canyon County to the intersection with Parma Drain, near Sharp Lane, in Canyon County. The designated uses of the AU are MOD (not yet approved by EPA) and SCR and it is listed in the draft 2008 Integrated Report for sediment, bacteria, DO, and unknown pollutants. This stream is a tributary to the Snake River, but is located in the Lower Boise River subbasin. It was not included in the TMDL and does not have LAs or targets for any pollutants. The channel has been modified to support agricultural canals, laterals, and drains, and the natural channel morphology is almost impossible to identify. There are approximately 6 flow control structures and at least 35 drains delivering agricultural effluent into Sand Hollow Creek in this AU. Upstream of Hwy 20/26, natural meanders are absent, with sinuosity and uncontrolled flow gradually reestablished downstream of Highway 20/26.

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DEQ is collecting water quality data in this AU this year (2008). Data indicate that one single-sample bacteria analysis exceeded criteria. Geomean bacteria data has not been collected and DO, pH, and temperature meet criteria. Sediment concentrations exceed TMDL targets and phosphorus concentrations may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. It is recommended that this AU be de-listed for DO and unknown, scheduled for development of a sediment TMDL, and listed in Section 4c for flow and habitat alteration in the next Integrated Report. 017_06 This AU includes 6th order Sand Hollow Creek from the intersection with Parma Drain to the boundary of the HUC. The designated uses of the AU are MOD (not yet approved by EPA) and SCR and it is listed in the draft 2008 Integrated Report for sediment, nutrients, DO, and unknown pollutants. This stream is a tributary to the Snake River, but is located in the Lower Boise River subbasin. This AU has TMDL LAs for total phosphorus in the Snake River-Hells Canyon TMDL (IDEQ, ODEQ, 2004). The channel has been straightened and confined to support agricultural land uses and there are at least two flow control structures and three drains delivering agricultural effluent into Sand Hollow Creek in this AU. Some natural sinuosity is preserved and the presence of water in abandoned channels, oxbows, and ponds indicates some hydraulic connection with shallow ground water. ISDA collected water quality data for this AU in 1998, 1999, and 2008. Data from 1998 and 1999 can be used as Tier II data for use attainment decisions. Data indicate that 85% of single-sample bacteria analyses exceed criteria, but geomean bacteria data has not been collected. Sediment concentrations exceed TMDL targets and appear to exceed criteria, and phosphorus concentrations may exceed recommended concentrations of 0.07 mg/L (Snake River-Hells Canyon TMDL, IDEQ, ODEQ, 2004) for the LA to the Boise River. All other criteria are met. This AU should be listed in Section 5 for bacteria and sediment and Section 4c for flow and habitat alteration in the next Integrated Report.

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Section 4. Review of Implementation Plan and Activities Implementation Plan The TMDL implementation plan (plan), published in 2003, addresses the 1999 sediment and bacteria TMDL, approved in 2000, developed for the four mainstem stream segments of the Boise River listed on the 1996 303(d) list. The plan designates pollution control efforts for point sources, urban and suburban storm water, agricultural nonpoint sources, and other nonpoint sources. The plan includes a watershed implementation schedule with milestones and an estimate of the date that WQS are expected to be met. In order to provide information to the public on water quality issues affecting the subbasin, the WAG maintains an internet site with information on WAG activities, cooperative projects, contracted and related studies and general water quality information. This website can be accessed at http://www.lowerboisewatershedcouncil.org/.

Responsible Parties The TMDL implementation plan was developed through resource management agency and stakeholder participation in topic-specific workgroups, facilitated by the WAG. The plan includes monitoring locations and targets for the sediment and bacteria TMDL, urban and suburban stormwater control plans, point source control mechanisms and nonpoint source control plans for the subbasin. The participants included highway districts, water districts, federal land management agencies, cities, counties, industry representatives, private citizens and state agency personnel (Figure 44). All parties share responsibility for implementing the plan.

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Figure 44. Diagram of participants and activities related to the Lower Boise River TMDL (DEQ, 1999), as copied from Figure 12 of the implementation plan (DEQ, 2003) for the Lower Boise River TMDL.

Planned Activities In an effort to identify and prioritize pollutant reduction methods, the WAG commissioned studies to determine proportional sources of bacteria throughout the subbasin, develop an effluent trading program and conduct use attainability analyses on several tributaries in the subbasin. These studies were completed by 2003. Nonpoint source workgroups identified funding as a variable upon which voluntary activities were dependent. The nonpoint source sector representatives stated that, if necessary equipment were replaced as needed and funding remained certain and doubled every 20 years, milestones identified by the group could be achieved and WQS would be attained in 103.1 years. Milestones identified by the group that can be quantified through tracking of BMP implementation and maintenance methods are as follows:  By 2010, 25 percent of all agricultural producers will have BMPs in place to prevent contributing sediment and bacteria pollution to waters in the subbasin.  Complete implementation of water quality plans and/or contracts on the initial agricultural acres within 5 years from contract approval.  Develop water quality plans/contracts and/or other BMP improvements for the next 25 percent of agricultural producers (owners or renters) by Year 20. To accomplish the goals of the TMDL the nonpoint source sector representatives identified specific management practices that contribute to sediment and bacteria

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pollution, and developed a method to prioritize lands and watersheds in the subbasin for BMPs designed to eliminate pollution from nonpoint sources. Orphan sources of nonpoint source pollution were identified and agencies responsible for sector-specific activities (roads, septic systems, water treatment infrastructure, etc.) identified methods for implementing BMPs that apply to regulated point sources to each nonpoint orphan source. Point source sector participants are regulated in accordance with federal laws and are subject to enforcement action if found in noncompliance with permit conditions or water quality regulations. These regulated entities identified specific milestones related to achieving permit requirements for stormwater and WWTP NPDES permits. All highway districts, cities, counties and responsible agencies within the subbasin committed to implementing permit-related BMPs and programs and meeting minimum percent removal requirements, even if permits were not currently in place. The activities identified included developing cooperative partnerships to improve efficiency and share resources, developing adaptive management techniques with measurable goals and integrating plan activities with permit requirements. These activities were planned to be completed and BMPs in place within 6 years (by 2007). The workgroups identified activities that would support the reasonable assurance requirement of the TMDL. A monitoring plan, implementation tracking database, reporting process and schedule were developed to track progress and establish a feedback loop for the WAG as summarized in Table 20.

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Table 20. Roles and responsibilities for reporting on TMDL progress in the Lower Boise River subbasin (as presented in Table 16 of the 2003 implementation plan).

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The WAG planned to voluntarily lead the process of reporting and tracking progress, and if needed, consider whether adjustments/revisions are necessary on behalf of subbasin stakeholders. Some of the milestones identified in the plan are: 

Agriculture



 Report annually on status and results of BMPs installed with public funds on private lands.  Track and report privately funded BMPs.  Develop water quality plans/contracts/BMPs for 25 percent of agricultural producers by 2010 and 50 percent by 2020; and initiate plans as soon as contracts are approved.  Initiate implementation of water quality plans and/or contracts on the initial agricultural acres as soon as contracts are approved.  Complete implementation of water quality plans and/or contracts on the initial agricultural acres within 5 years from contract approval.  Develop water quality plans/contracts and/or other BMP improvements for the next 25 percent of agricultural producers (owners or renters) by Year 20. Highway Districts



 Determine the need for erosion control plans within one year (by 2001).  Train staff to develop erosion control plans by year two (2003).  Develop Cooperative Management Plan for agricultural activities within 3 years (by 2004) and form cooperative agreements with other agencies to implement BMPs required under municipal separate storm water system (MS4) permits (by 2006).  Develop BMP Manual for Road Maintenance Activities. Monitoring Program  Point sources will perform monitoring related to permit requirements  Nonpoint source monitoring will be performed by ISDA and will monitor results of implementation on agricultural lands and report annually on TMDL progress. This will include BMP effectiveness and maintenance monitoring for every BMP project.  Ada County Highway District (ACHD), city of Boise, Drainage District 3, Boise State University, Idaho Transportation Department region 3 will monitor as required by the stormwater NPDES permit.  Smaller stakeholders (Caldwell, Nampa, Nampa Highway District, Canyon Highway District, and Notus-Parma Highway District) may implement monitoring as part of the voluntary implementation of minimum permit requirements.  Stakeholders and agencies will monitor and document their progress and will provide the information annually to DEQ.  DEQ is responsible for long-term monitoring of a jointly funded (USGS, WAG, BOR, and DEQ) monitoring program designed to evaluate the lower Boise River and its tributaries. The WAG and BOR and USGS will direct and fund the program after 2003.

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 ISDA and the USGS will monitor tributaries and mainstem locations after 2002 and DEQ will add priority tributaries to the BURP schedule for 2003.  DEQ will summarize four issues on a 5-year cycle: TMDL implementation effectiveness; point source compliance with NPDES permits; subbasin water quality; and overall status of beneficial use attainment of the subbasin. Data Analysis  Analysis of available monitoring data will be performed every five years by DEQ to determine effectiveness of BMP measures and progress toward TMDL attainment.  Results will be used to recommend or discourage future projects.  Monitoring parameters will be modified to reflect any new or revised standards.  Substrate monitoring will receive DEQ participation if EPA re-initiates the project abandoned in 2000.  Data gaps will be addressed as resources allow.  A tracking database for nonpoint source projects was planned to mirror the existing Soil Conservation Commission (SCC) tracking database.

All of the items identified in the plan are contingent on funding. Activities required to reduce pollutant loads to the lower Boise River require investment on a consistent long term basis in order for TMDL targets to be achieved and maintained. The tracking and reporting method specified in the implementation plan established an annual and a fiveyear reporting process, with regulatory agencies or permitted facilities required to track and report and all other participants committing to voluntarily track and report as described in the plan. In order to assess progress toward TMDL targets, a monitoring plan was to be developed and enacted. Results of the monitoring effort were to be reported to the WAG yearly and the WAG would include those results in its annual report to DEQ.

Accomplished Activities Stormwater is regulated at the federal level and the implementation plan recognizes that when required BMPs are implemented through the federal permit system, stormwater contributions of pollutants to impaired waters in the subbasin will diminish. In order to achieve the goals of the TMDL in an efficient and cost-effective manner, a watershed prioritization approach was developed. The watersheds that best met criteria outlined in the plan by location, load and growth were given higher priority (in alphabetical order) for TMDL implementation projects. At the time the implementation plan was developed those watersheds were: Dixie Slough (AU 001_06), Fifteenmile Creek (AU 007) (including Fivemile (AU 010) and Tenmile (AU 008) Creeks), Indian Creek (AU 002, AU 003) and Mason Creek (AU 006). A BMP projects tracking database was developed to use as a tool to arrive at prioritization decisions. Stormwater dischargers anticipated meeting TMDL targets within 10 years of implementation. Nonpoint sources in the subbasin are primarily from the agricultural industry sector. Presently, the CWA and Idaho WQS specify that irrigated agriculture pollution control is voluntary and return flows from irrigated agriculture are specifically excluded from the

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definition of “point source” in the CWA. However, Idaho has invested in creating several agencies and elected groups to address nonpoint source pollution through industry/activity-specific BMP development. These agencies and organizations developed a component of the TMDL implementation plan to provide guidance and support to members of the agricultural community who choose to voluntarily reduce or prevent pollution from agricultural activities entering subbasin waters. The objectives of the agricultural BMPs are to restore the attainment of beneficial uses of the Lower Boise River through reducing sediment and bacteria pollution from agricultural sources. The implementation plan also includes goals to improve salmonid spawning habitat and educate the agricultural community about water quality and the TMDL process. Some of the projects that the WAG has initiated since the publication of the TMDL include a Use Attainability Analysis (UAA) of tributaries and drains in the subbasin (2002) (http://www.lowerboisewatershedcouncil.org/05_water-quality/sedbacteria/subbasin/UAA/LBR_UAA_RevisedTechMemo.pdf) and a Water Quality Trading Project (2000-2003) which can be accessed at the following internet site: (http://www.deq.state.id.us/water/data_reports/surface_water/tmdls/boise_river_lower/boise_river _lower_effluent_status02.pdf).

Several designated agencies are responsible for development and oversight of sourcespecific TMDL implementation plans. The primary purpose of this report is to review the progress of TMDL implementation and measure progress in attaining beneficial uses and current WQS. Point Sources The lower Boise River subbasin uses watershed-based permitting for stormwater NPDES permits. This allows for an integrated approach to a watershed-wide program. Based on the information provided by permitted point sources within the subbasin, permit holders are in compliance with permit conditions. Based on the information provided by the responsible agencies, stormwater and point source compliance monitoring in the Boise urban area is taking place as anticipated by the TMDL implementation plan. Several agencies and organizations share responsibilities for the Boise area NPDES MS4 permit and information on meetings, responsibilities, budgets and reports is available from the partnership internet site http://www.partnersforcleanwater.org/default.asp. An annual report is published and made available through ACHD’s web site at: http://www.achd.ada.id.us/Departments/TechServices/Drainage.aspx. All of the required stormwater annual and five-year reports have been created and NPDES stormwater copermitees make their reports available through a partnership internet site http://www.partnersforcleanwater.org/Annual%20Report.asp. Other agencies and stakeholders in the subbasin are in the process of applying for stormwater NPDES permits and have yet to develop or implement the voluntary stormwater activities as described in the plan. A multi-agency effort produced the BMP Handbook of Best Management Practices for Idaho Rural Road Maintenance (University of Idaho, 2005) and highway district personnel were trained in the methods through a training program funded with public funds through various agencies.

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Nonpoint Sources ISDA collected water quality data from 11 tributaries and drains in the subbasin from 1997 through 2003 and published a brief report on each subwatershed. An agricultural BMP implementation plan and a guidance document for evaluating effectiveness were developed in 2003. The TMDL implementation plan for agricultural lands identifies critical acres and prioritizes land for BMPs by identifying acres that have the greatest effect on pollutant delivery to the Boise River as Tier I lands. For sediment pollutant reduction, priority acres are surface-irrigated croplands with the steepest slopes or closest to the Boise River, and riparian acres grazed by livestock. The highest priority watersheds for agricultural BMP implementation to reduce sediment pollution are Dixie Slough (AU 001_06), Fifteenmile Creek (AU 007) (including Fivemile (AU 010) and Tenmile (AU 008) Creeks), and Mason Creek (AU 006). For bacteria pollutant reduction, critical acres were identified as irrigated pasture, dairy operations, and feedlots. Many livestock operations in Idaho do not meet the EPA definition of an Animal Feedlot Operation (AFO) or Confined Animal Feedlot Operation (CAFO) but contribute sediment and bacteria pollutants to the Lower Boise River. If a facility meets the definition of an AFO or a CAFO, a federal NPDES permit must be obtained and BMPs to limit pollution must be implemented. Dixie (AU 001_06) and Mason Sloughs (AU 006) were identified by the workgroup as priority watersheds for bacteria related to agricultural uses. Table 21 includes information provided to DEQ by ISDA personnel in response to requests for details regarding TMDL implementation on agricultural lands in the subbasin. A copy of the detailed report is in Appendix D. The percent of producers implementing and maintaining BMPs is unknown at this time. Annual reports to the WAG have not been developed by ISDA, county soil conservation districts, or Idaho Association of Soil Conservation Districts. For the purposes of providing BMP information for this review, the SCC has reported that 74.1 percent of BMPs implemented have been on Tier III (low priority) agricultural lands and 18.6% of BMPs have been applied to Tier I (high priority) agricultural lands (Appendix D). Table 21. Implementation activities in progress and planned for the Lower Boise River subbasin as of May 2008. AU

Year

Target Pollutant

undetermined

2004

Sediment

002_04

2004

Sediment

011a_06

2004

011b_02 011a_06

2005 2004

Sediment, bacteria Sediment, habitat and flow alteration Sediment

undetermined

Sediment, bacteria

Activity Jerry Glen wetland construction Indian Creek, Caldwell low impact development demonstration Downtown Boise gray water recycling demonstration Boise River side channel reconstruction Barber Park Living Roof demonstration Canyon County Soil Conservation District (SCD), 19 BMPs including a total of 13,666 feet of streambank protected and 35 acres treated

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Completion Status Completed Completed Completed Completed Completed

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Lower Boise River 5-year Subbasin Assessment and TMDL Review

AU

Year

Target Pollutant

001

Sediment, bacteria

001

Sediment, bacteria

007

Sediment, bacteria

Activity Canyon SCD, Conway Gulch, 141 BMPs including a total of 99,138 linear feet of streambank protected and 29,462 acres treated Canyon SCD, Dixie Slough, 75 BMPs including a total of 41,219 linear feet of streambank protected and 1,352 acres treated Ada Soil and Water Conservation District (SWCD), Fifteenmile Creek, 34 BMPs including a total of 14,125 linear feet of streambank protected and 983 acres treated

February 2009

Completion Status

Completed

Completed

Completed

In 2004, ISDA planned to provide maintenance and support to 45 water quality projects to support TMDL implementation throughout the state (ISDA, 2004). The ISDA 2003 and 2006 annual report states that the agency plans to “develop BMP effectiveness protocols for agricultural TMDL program” (ISDA, 2003, 2006).

Monitoring The WAG contracted with the USGS to monitor the Lower Boise River for compliance with the TMDL. The data is available through the USGS National Water Information System (NWIS) which is available through the internet at http://waterdata.usgs.gov/nwis/sw. The ISDA and DEQ also collect data in the subbasin and use the data in specific reports and programs. Because annual reports have not been created yet, in an effort to review data from all parties and sources, DEQ requested data for this report from the WAG at its March and May meetings. The data included in this report and appendices includes data retrieved by DEQ and data provided from federal, state and local agencies as indicated in Section 3, Table 12, of this report. The plan specified that monitoring would provide reasonable assurance that pollutant reductions will be achieved. The objectives of the monitoring plan are to determine BMP effectiveness for nonpoint and point sources and to monitor 18 control locations in the subbasin to determine general implementation effectiveness and beneficial use attainment status. Sediment Monitoring The implementation plan incorporates nonpoint source LA locations and loads for sediment at 16 locations downstream of the city of Middleton, and WLAs from 9 point sources throughout the subbasin. Two mainstem monitoring locations, USGS Middleton gage (13210500) and USGS Parma gage (13213000), were selected for sediment target (concentration) monitoring locations, as discussed in Section 3. The critical time period for sediment is February 15 through June 14. Table 22 summarizes the information

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available from those locations and compares the current available data to the 1995 data and the 37 percent needed reduction specified in the TMDL. Data in the Reported Load column of Table 22 was calculated using an average of the most recent data collected during the critical time period. If less than 10 values were available from the critical time period, all data collected in the past five years was averaged to determine a load value. Data is not available from all 18 control locations in the subbasin and is included in Appendix C. Discharge and sediment concentrations were averaged in the same manner as previously described and used in the calculation described in Computation of Fluvial-Sediment Discharge, (Porterfield, 1972) to determine the values in the Reported Load column. Of the 11 locations for which there is data, six have sediment load increases between 10 and 394 (estimated) percent and five have sediment load decreases between 25 and 45 percent. A determination of target achievement cannot be made for the seven remaining locations due to an absence of data. The sediment TMDL target reduction of 37 percent has been met or exceeded at Eagle and Thurman Drains, and Fifteenmile and Willow Creeks. However, based on reported data, Fifteenmile Creek (AU 007_04) sediment concentrations indicate a likely exceedance of turbidity criteria for COLD beneficial uses, and therefore can not be determined to support beneficial uses. Table 22. TMDL locations for tributary, nonpoint, and point source load allocations (LA) and wasteload allocations (WLA) for sediment and reported sediment data compared to TMDL targets. SSC/TSS LA or WLA Location Eagle Drain Thurman Drain Riparian Load #1 (Bubb) Fifteenmile Creek Star Feeder Long Feeder Watts Creek Mill Slough Willow Creek Mason Slough Mason Creek E. & W. Hartley Gulch E. & W. Hartley Gulch Indian Creek Conway Gulch Dixie Drain Riparian Load #2, #3 (Mason-Caitlin) Lander Street

TMDL Target Load (tons/day)

Reported Load, (tons/day) (2000, 2005, 2008)

005_06 005_06

1.61 0.34

1.11 (2000) 0.188 (2008)

31 45

Target Achieved (in percent) 100 100

007_04 005_06 005_06 005_06 005_06 015_03 006_02 006_02

2.45 28.6 2.75 0.56 0.45 7.08 2.28 1.20 21.48

No Data 16.11 (2005) No Data No Data No Data 5.33 (2005) 1.30 (2005) 1.40 (2005) 74.93 (2005)

Unknown 44 Unknown Unknown Unknown 25 43 16 (increase) 248 (increase)

Unknown 100 Unknown Unknown Unknown 67 100 0 0

005_06

5.31

6.27 (2005)

0

005_06 002_04 001_06 001_06

5.31 5.74 7.14 25.91

26.22e (2008) 7.73 (2005) 20.04 (2005) 36.04 (2005)

18 (increase) 394e (increase) 181 (increase) 10 (increase) 39 (increase)

0e 0 0 0

011a_06

4.90 1.7

No data 0.04 (5/2008)

Unknown Not applicable

Unknown 100

AU

100

Percent Reduction

Lower Boise River 5-year Subbasin Assessment and TMDL Review

SSC/TSS LA or WLA Location West Boise Meridian Nampa Caldwell Star Middleton Notus Armour (Swift)

AU 005_06 005_06 005_06 001_06 005_06 005_06 001_06 003a_04

TMDL Target Load (tons/day)

Reported Load, (tons/day) (2000, 2005, 2008)

3.4 0.355 1.5 1.0625 0.0965 0.535 0.0165 0.0625

0.03 (5/2008) 0.04 (5/2008) 0.04 (5/2008) 0.17 (5/2008) 0.011 (5/2008) 0.01 (5/2008) 0.05 (2007) No Data

February 2009

Percent Reduction Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable Unknown

Target Achieved (in percent) 100 100 100 100 100 100 0 Unknown

SSC – Suspended Sediment Concentration; TSS – Total Suspended Sediment; AU – Assessment Unit; e – Estimated value

Bacteria Monitoring The implementation plan details how compliance with the bacteria TMDL will be determined. The WQS for contact recreation uses at the time the TMDL was developed were based on a surrogate measure using fecal coliform concentrations. The target concentration for each location assigned an LA was 50 cfu/100mL during PCR critical times. The revised WQS (2007), not yet approved by EPA, use a surrogate measure of E. coli to determine contact recreation use attainment. The implementation plan explains how the E. coli surrogate measure will be applied as the target for TMDL achievement. WQS apply to calculated geomean concentrations from a minimum of five samples in 30 days, triggered by an exceedance of single sample concentration maximum values, with the standard set at 126 cfu/100mL for PCR/SCR. As geomean data is not available for most LA locations, Table 23 uses an average of the E. coli single sample concentrations reported for the most recent year (2000, 2005, and 2008) to determine achievement of the TMDL geomean bacteria target goal. Stormwater sources must comply with permit limits that cannot exceed WQS, so those sources did not receive a WLA for bacteria in the TMDL. Table 23. Bacteria data at TMDL control locations for tributary and nonpoint sources compared to TMDL Addendum (2007) targets (126 geomean cfu/100mL). SSC / TSS LA or WLA Control Location Eagle Drain Thurman Drain Fifteenmile Creek Mill Slough Willow Creek Mason Slough Mason Creek East & West Hartley Gulch Indian Creek Conway Gulch Dixie Drain

AU 005_06 005_06 007_04 005_06 015_03 006_03 006_03 005_06 002_04 001_06 001_06

1999 geomean Fecal Coliform Concentration (cfu/100mL) 604 758 992 1,282 803 3,507 1,407 2,296 770 723 2,987

Reported E. coli Concentration (cfu/100mL) (2000, 2005, 2008) 255 (2000) i 48 (2008) i 1,238 (2005) i 438 (2005) i 798 (2005) i 3,768 (2000) i 838 (2000) i 767 (2008) i 193 (2005) i 502 (2005) i 3,130 (2005) i

SSC – Suspended Sediment Concentration; TSS – Total Suspended Sediment; AU – Assessment Unit; i – instantaneous: single sample

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The WAG received grant funds to conduct a bacteria DNA-typing study in the subbasin (2000-2003) to facilitate the development of BMPs to achieve reductions in bacteria loads required to meet TMDL targets. These projects are supported by a variety of funding sources, including DEQ, the Idaho Soil Conservation Commission (SCC), the USGS and EPA. The results of that study were intended to guide future implementation efforts in the subbasin and identified that human and domestic pet sources of bacteria are dominant controllable sources upstream of Glenwood Bridge and that human, domestic pets and livestock sources are dominant controllable sources downstream of the Glenwood Bridge; with the highest prevalence of livestock sources at the Dixie Slough and Parma locations. Controllable sources of bacteria (humans, domestic pets and livestock) throughout the subbasin ranged from 27 to 56 percent. The critical time period for bacteria is year-round, so data collected throughout the year can be used to determine achievement of WQS and the TMDL. The implementation plan includes a sampling plan that was developed to address data gaps in the TMDL dataset. Stormwater BMPs and permit WLAs for point sources were believed to be sufficient to meet the TMDL for stormwater and point sources. For nonpoint sources bacteria load reduction needed at control monitoring locations varied from 70 to 99 percent. Near the Thurman Drain sampling location land use has been modified from agricultural to urban uses since the TMDL was developed and it is the only nonpoint source control monitoring location observed to have achieved the TMDL target for bacteria. Wildlife and waterfowl have been observed at the sampling location, but as human population densities increase, population density of wildlife usually decreases.

Future Strategy The status of beneficial use attainment for surface water bodies in the Lower Boise River subbasin is described and summarized in the Executive Summary and Section 3 of this report. Beneficial use attainment was determined by reviewing all of the available pertinent data from the sources identified in Section 3, Table 12. Revising the data collection plan so that data is collected from all control monitoring locations on a regular basis, and creating annual reports as intended in the plan, will facilitate use determination accuracy for future five-year reviews. Based on the data reviewed for this report, bacteria criteria for beneficial uses were exceeded in ten AUs, TMDL sediment targets for beneficial uses were exceeded in nine AUs, and temperature criteria were exceeded in five AUs. Two TMDLs should be scheduled for temperature, two for bacteria, and one for sediment. For the next Integrated Report, nine AUs should be added to Section 3 and seven AUs should be added to Section 5. Thirty AUs should be added to Section 4c for flow/habitat alteration. One AU, 013_03 (Dry Creek) should be added to Section 2 as meeting all presumed uses. DO and pH are within criteria for beneficial uses in all AUs. Sediment LA targets established in the TMDL have been achieved at four of 16 nonpoint source monitoring locations, but three of those four AUs still exceed TMDL sediment targets and/or turbidity criteria, based on results reported at other locations in the AU. There is a need for BMP effectiveness and ambient water quality monitoring throughout the subbasin, but widespread historic flow and habitat modification may be the most prevalent primary cause of water quality impairment in the subbasin.

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Adaptive management appears to be a reasonable strategy for taking steps to encourage voluntary watershed restoration or pollution prevention projects, but not enough data has been collected to determine if that approach will yield significant benefits.

Time Frame The time frame for all regulated sources in the subbasin to achieve WLAs was met only in the Boise urban area. It is not possible to estimate how long it will take the other area stormwater sources to implement BMPs identified in the plan. An absence of effectiveness monitoring and annual reporting for nonpoint sources makes it difficult to determine if milestones have been met for this sector. Due to the nature and scope of flow and habitat modification, restoring water quality to full use attainment may not be possible in all AUs of the subbasin. For example, it is unlikely that aquatic organisms will thrive in a dewatered or unstable stream environment.

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Section 5. Summary of Five Year Review Review Process The process to create this report in a manner compliant with Idaho Statute 39-3611 (7) includes a review of existing TMDLs, SBAs, public databases, current and draft integrated reports and other published reports on the lower Boise River subbasin. A call for data was made at the March 13 and May 13 (2008) WAG meetings. Data and information is reviewed in relationship or comparison to designated, existing, or presumed beneficial uses and applicable WQS. This report compared review data to the TMDL targets, designated or presumed uses and WQS (2007, not yet approved by EPA). In order to determine if the existing use may be different than the designated or presumed use, DEQ searched for fish community data collected in the past 10 years to determine if SS exists in AUs not presently designated for that use. DEQ determined that SS exists in AUs designated for that use, but do not appear to exist in AUs not designated for SS. DEQ also contacted the IDFG to verify the applicable spawning periods for the AUs with SS as a designated use. IDFG confirmed that the SS time periods listed in Table F-1 of the WBAG II (Grafe, et al., 2002) are valid for the lower Boise River subbasin (Jeff Dillon, IDFG, personal communication, January 22, 2009) Data was determined to be relevant if it met the criteria described in detail in the WBAG II (Grafe, et al, 2002). This review used Tier I and Tier II data to make comparisons to targets and standards and to determine existing uses where data was available.

Changes in Subbasin There are some changes in the subbasin that are likely to have an effect on water quality. Approximately 50,000 acres of agricultural land (6 percent of land identified as agricultural in the TMDL) was converted to urban/suburban use between 2000 and 2005 (U of I, 2005). At that rate, approximately 1.2 percent of the subbasin area is added to urban/suburban land use each year. Not all of this converted land has been annexed by cities and much of it is managed as small acreages by private landowners. BMP implementation on transitional land through voluntary compliance with federal and state regulations may be more challenging than working with traditional agricultural producers. As cities annex transitional lands, water use for irrigation may decline and result in less water diverted from the mainstem and less sediment and bacteria pollution delivered to the Boise River. This change is not evident in the data reviewed for this report. Point sources may not have increased in number, but facilities required to operate within the NPDES permit system have increased. Currently, there are 19 municipal and 43 nonmunicipal permitted wastewater dischargers in Canyon and Ada counties listed on EPA’s website (http://oaspub.epa.gov/enviro/ef_home2.water) and four additional facilities are in the process of applying for a permit. This represents a four-fold increase in permitted facilities in the subbasin since the TMDL was developed. Part of this is due to an 105

Lower Boise River 5-year Subbasin Assessment and TMDL Review

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increase in the number of point-source facilities and part of this is due to increased regulation of facilities not regulated when the TMDL was developed. The increase in the number of facilities has reduced the reserve for suspended sediment by 0.522 tons/day, to 3.098 tons/day (IDEQ and LBWC, 2008).

TMDL Analysis The SBA developed with the TMDL applied the WQS for bacteria, sediment, turbidity, nutrients and temperature for comparison with available data, to determine the type and degree of impairment to the lower Boise River. The SBA indicated that some pollutants (DO, Oil & Grease) listed on the 1996 303(d) list were not impairing beneficial uses and those pollutants were delisted in 1998. In reviewing the available pertinent data, that determination is supported. The SBA also identified that bacteria, sediment and temperature were impairing beneficial uses in the lower Boise River. Bacteria and temperature were documented as exceeding numerical WQS criteria. Sediment was determined to be an impairment using empirical methods to synthesize visual observations and fish community and water column data compared to thresholds identified in appropriate literature. Literaturederived numerical targets were selected for 14 and 60-day intervals to protect the most sensitive beneficial uses (COLD and SS) and available data were compared to those targets. Because tributaries were identified as load sources, LAs were assigned to 11 tributaries and two mainstem river locations for bacteria, and 12 tributaries and three mainstem river locations for sediment. Bacteria The targets for bacteria were derived based on the numeric geomean concentration criteria for PCR and SCR (126 E. coli cfu/100mL). The needed reductions at LA and control monitoring locations range from 76 to 99 percent. An E. coli DNA ribo-typing study (LBRWQP, 2003) determined that 27 to 56 percent of sources are controllable. Using numerical WQS criteria for bacteria targets is supported by research and EPA as a valid method for determining attainment of beneficial uses. Sediment Load reductions for sediment were determined based on 1992 (lowest flow year on record) low-flow 90th percentile calculated geomean concentrations at the mainstem river control monitoring locations. A mass-balance analysis was used to determine that a 37 percent reduction was necessary to meet the TMDL targets. A mass-balance approach using low flows during times of year when reported analysis results are the highest to calculate a percent reduction necessary to achieve TMDL targets is a valid approach to establishing targets. Subsequent SBAs for the subbasin tributaries evaluated maximum concentrations of suspended sediment detrimental to fish that may be present for short durations some time of the year. However, those calculated maximum values are likely to exceed turbidity criteria for COLD designated and presumed uses for the tributaries and may not be an acceptable load for those tributaries. The sediment TMDL Addendum (DEQ, 2007) developed a process for allocating loads to permitted sources from the load that is reserved for growth; however, there is no reserve

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for growth that can be allocated to stormwater sources in the TMDL because stormwater was categorized as a nonpoint source pollutant. The TMDL acknowledged the discrepancy between how stormwater was categorized in the Lower Boise River subbasin and other subbasins nationwide, and the EPA recommends that stormwater be categorized as a point source and given a WLA that is then incorporated into the NPDES permit. Given the likely future increases in stormwater from urbanized areas as agricultural lands are converted to suburban and urban land uses, this may be a necessary revision to the sediment TMDL. A phosphorus implementation plan has been developed for the subbasin that addresses the issue of increased WLAs for stormwater as LAs for agricultural sources are decreased, and this may be an appropriate method for revising the sediment TMDL or Addendum. Using the feedback loop to review data collected at control monitoring locations and at ISDA BMP-effectiveness monitoring locations is a critical part of determining whether or not a uniform proportion of reduction will actually achieve beneficial uses as defined by the dual target concentrations. Using numerical literature-derived targets for sediment is supported by research and EPA as a valid method for determining attainment of beneficial uses. Temperature The SBA discusses temperature criteria for SS compared to available data at several locations, including Parma. As Parma was/is not designated for SS, and no data exist to indicate that SS was/is an existing use, this comparison could be misinterpreted as an exceedance of criteria. The SBA also discusses exceedance of SS criteria downstream of Middleton being primarily from natural sources. Data was not collected between Glenwood Bridge and Middleton and only 3 of the 12 identified contributing drains and tributaries were monitored for temperature. Although the SBA explains that mainstem water temperatures closely track air temperatures during the irrigation season, there is no mention of the close correlation between water diversions and drains and increased mainstem water temperatures. Data is insufficient to eliminate drains and tributaries upstream of Middleton from the source inventory. In view of the fact that approximately 80 percent of mainstem river flow is diverted in the Boise area for surface irrigation of approximately 255,000 acres and then returned to the mainstem at numerous locations between Star and Caldwell (IDWR, 2008; BOR, 2007; ACOE, 1995), any temperature assessment should include all diversions and drains in the pollution source inventory. The conclusion that climate conditions control the water temperatures of the lower Boise River may have overlooked the load contributed by return drains. The TMDL developed sediment and bacteria LAs for tributaries known to contribute water to the lower Boise River and assigned locations for control monitoring at the mouths of 12 tributaries and drains and 3 locations in the mainstem river to determine TMDL attainment. The SBA and TMDL suggested that additional analysis or considerations be initiated to address temperature impairment issues. Using numerical WQS and numerical literature-derived targets is supported by research and EPA as a valid method for determining attainment of beneficial uses.

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Review of Beneficial Uses Since the SBA and TMDL were developed Idaho has adopted a method of identifying waters by AU instead of stream-reach-specific geographical descriptions of surface water bodies (DEQ, 2002). Using this method, the lower Boise River subbasin includes 36 AUs, 23 of which were listed as impaired in Table 9 of the 2002 Integrated Report and 24 of which are listed as impaired in the draft 2008 Integrated Report (Figure 1, Table 11). The results of the review are presented in Section 3, Table 19 and the accompanying Summary of Recommendations. There is one AU in the lower Boise River subbasin that fully supports beneficial uses.

Water Quality Criteria In 2001 Idaho WQS were modified to use numeric criteria for E. coli as a surrogate measure for recreational beneficial uses instead of fecal coliform numeric criteria. The implementation plan was developed to accommodate this change and uses the appropriate numeric criteria as the target for recreational beneficial uses. In 2004, EPA approved a UAA submitted by DEQ in 2002 to modify the recreational beneficial use of some AUs in the lower Boise subbasin from PCR to SCR (EPA, 2004). In 2007 Idaho WQS were revised to include site-specific beneficial uses and criteria for some AUs in the Lower Boise River subbasin. Those changes are reflected in Section 3; Table 10, Figure 5 and Table 11, and have not yet been approved by EPA.

Future TMDLs Not all of the water bodies listed as impaired in the draft 2008 Integrated Report will require a TMDL. However, a thorough review of available data was completed before this conclusion was made. This review evaluated appropriateness of WQS to designated uses throughout the subbasin and compared available data to WQS to determine use attainment. The most common impairment to water quality throughout the Lower Boise River subbasin is a result of human occupation and associated exploitation of resources in the subbasin to support the population, and is not subject to allocations through the TMDL process. Flow and habitat alteration coincident with population expansion is documented in numerous reports to have begun as early as the mid-1800s (MacCoy and Blew, 2005; ISHS, 1993). Temperature and sediment pollution is closely linked to flow and habitat alteration, while nutrient, bacteria, DO, pH and other impairment causes are more closely related to effluent contributions from human sources. As mentioned in the implementation plan, AUs that do not meet WQS due to influence of a pollutant for which a TMDL should be written will be recommended for listing in Section 5 of the next integrated report, which will lead to TMDL development for pollutants that can be quantified and for which loads can be allocated. For AUs that have data which indicate the AU is inappropriately listed recommendations will be made to correct the listing status.

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Watershed Advisory Group Consultation In compliance with consultation requirements in Idaho Code § 39-3611, DEQ has met regularly with the Lower Boise Watershed Advisory Group (WAG). A WAG for the Lower Boise River TMDL was appointed by the state from an existing non-profit organization (Lower Boise Water Quality Plan, now the Lower Boise Watershed Council). The group met regularly over the course of the development of the 1999 TMDL and continues to hold regular public meetings in Boise and Caldwell. Minutes from meetings for the previous two years are available on the Council’s web site at: http://www.lowerboisewatershedcouncil.org/05_water-quality/environmentallaws.html#wag. In 2008 the WAG met on January 10, February 14, March 13, April 10, May 13, June 12, August 14, September 11 and November 13. A call for data was made at the March 13 and May 13, 2008, WAG meetings. Data was received from several WAG members and agencies that were contacted by the WAG or referred to DEQ by the WAG. The results of that interaction and consultation are included in the information presented in this report and summarized in Table 24. Table 24. Summary of recommendations and comments from the Lower Boise Watershed Advisory Group. Recommended Action Break out riparian areas in the TMDL and allocate loads by AU

Schedule 2013

Responsibility DEQ

Work with Idaho Department of Fish and Game (IDFG) to develop a salmonid spawning (SS) table for the Lower Boise River AUs with designated use for SS to be included in Idaho’s Water Body Assessment Guidance (WBAG). Develop a revision to the sediment TMDL/Addendum that re-categorizes stormwater from a nonpoint source to a point source. Recalculate sediment load allocations to stormwater sources and determine WLAs for those point sources. Add discharge and water temperature data from a 2005 report (developed by the city of Boise) to this review.

Immediate

DEQ

Add average daily temperature to data tables of temperature data provided by the city of Boise.

Justification To update the pollutant LAs for sediment to reflect the change from stream segments to AUs and facilitate determination of attaining TMDL targets. To better define the time periods that SS temperature criteria would apply in the AUs designated for SS beneficial uses. (Communication with Jeff Dillon of IDFG, January 22, 2009 confirms that common core periods identified in Table F-1 of WBAG II (2001) are applicable to the Lower Boise River.) To enable a revision or creation of a WLA to stormwater sources as land use changes in the subbasin from agricultural to sub urban/urban uses. Categorizing stormwater sources as point sources is supported in EPA guidance for TMDL development.

Immediate

Immediate

City of Boise and DEQ

DEQ

Water temperature data was collected from several drains and tributaries in the subbasin in 2004. Even though that data was not provided in response to the call for data in March and May, it is believed to be a useful data set and should be included in this report. Data provided by Johanna Bell, City of Boise, on January 22,2009 is included in an abridged format in Appendix C. Provides better information to readers. Daily Average data was added to Appendix C.

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Recommended Action Add information about the new Multi Sector General Permit (MSGP) for stormwater.

Schedule Immediate

Responsibility DEQ

February 2009

Justification The permit information provided in the Pollution Source Review section of the review would be helpful and a link to the permit web page would benefit industries and operators required to comply with the permit.

General Comments and Response 

















De-listing AU 003_04 for sediment and listing AU 003_04 for sediment seems counter-productive. o DEQ understands that recommendations to de-list and list adjoining AUs for sediment may appear contradictory; however, the recommendations are based on a review of available data and any future TMDL development will consider and evaluate the contribution of sediment loads from unlisted but adjoining AUs. Current data serve to identify specific locations where criteria are exceeded and are not intended to exclude locations or sources not yet identified. The use of the word “effluent” in Figure 10 should be clarified that the effluent is not from a Wastewater Treatment Plant (WWTP), but is waste material from multiple sources discharged to the Boise River. o The definition in the Glossary has been modified as suggested and the document has been modified to clarify that effluent plumes identified in Figure 10 are not from WWTPs. Recognize that the sediment concentration targets in t he TMDL are for the mainstem and that different targets were identified for the tributaries in the 2001 tributary Subbasin Assessments (SBAs). o DEQ understands that the sediment targets in the TMDL are to be evaluated in terms of dual concentration targets in the mainstem river and by percent load reduction at identified tributaries. While suspended sediment loads were evaluated in the 2001 SBAs in comparison to published salmonid sensitivity, Idaho WQS (Figure 11) apply to waterbodies designated or presumed to support COLD uses. This review identifies water bodies and AUs for which reported data indicate exceedance of WQS criteria and recommends listing and TMDL development for sediment based on criteria exceedance and/or use support. Add some explanation for pollution sources to Fifteenmile Creek for sediment (including Fivemile, Tenmile and Blacks Creeks). o DEQ has modified Section 3 of this report to include some discussion of potential sources of sediment impairment to Fifteenmile Creek. Make sure that the sediment data from tributaries is compared to the appropriate WQS criteria and targets. o DEQ has reviewed the data for suspended sediment, compared the data to the TMDL targets (concentration for mainstem, load reduction for tributaries) and other observations to verify that the recommendations are appropriate at this time. Check with IDFG to verify spawning time frames. o DEQ has communicated with Jeff Dillon, of the IDFG, to confirm that the general time frame identified in the WBAG II (Grafe et al., 2001) is the time frame that is appropriate for the Lower Boise River given the current body of published research. Bacteria reduction goals are difficult to quantify because of the change in surrogate measures from fecal coliform to E. coli. How are we evaluating progress on the bacteria TMDL? o DEQ agrees that comparing current E. coli concentration data with historical fecal coliform concentration data is not a useful measure to determine TMDL progress. Table 23 has been revised to present current bacteria concentration data and provide information regarding the current WQS. The next review will provide a better opportunity to evaluate trends and progress toward bacteria TMDL attainment. Because of the relative permanent locations and associated activities, Multi-Sector General Permits (MSGPs) for Industrial Stormwater facilities should be listed. By February 12th, 2009 the MSGP ENOI database will be up and running for Idaho. o Annotation of “available for online query in the future” will be added in reference the MSGPs, but as the number of facilities is in constant flux for many industries, the information is available to the public through paperless media, the database won’t be functional until after this report is final and the MSGP identifies entities prohibited from contributing pollutants to the system, information for interested parties to compile a list for the subbasin from that source will be included. In general, compiling a list of entities excluded from contributing pollutants to the system is less useful than compiling a list of entities permitted (NPDES) to contribute pollutants to the system. Even though the Construction General Permits (CGPs) are transient in nature, an estimated number of permits and associated number of acres could probably be queried and presented for the 5-year period. o As the CGP facilities are required to keep all stormwater onsite and/or treat all runoff, this is not a potential source of pollutants to waters of the subbasin.

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In response to the general comments offered by the WAG, in consultation with DEQ to create this report, DEQ has taken action on some items, revised the document and contacted other agencies to confirm information in this report. The results of these actions and reviews are included in Table 24.

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References Cited Ada County Drainage District 3. NPDES Annual Report, Permit Year 2006-2007. Boise, ID. Retrieved from http://www.partnersforcleanwater.org/Annual%20Report.asp. August 2008. Ada County Highway District. 2002-2007. NPDES Municipal Separate Stormwater System Annual Report. Boise, ID. Retrieved from http://www.achd.ada.id.us/Departments/TechServices/Drainage.aspx. August 2008. American Geological Institute. 1962. Dictionary of geological terms. Doubleday and Company. Garden City, NY. 545 p. Armantrout, N.B., compiler. 1998. Glossary of aquatic habitat inventory terminology. American Fisheries Society. Bethesda, MD. 136 p. Batt, P.E. 1996. Governor Philip E. Batt’s Idaho bull trout conservation plan. State of Idaho, Office of the Governor. Boise, ID. 20 p, plus appendices. Boise State University. 2006-2007. Stormwater Management Plan Annual Report. Boise, ID. Retrieved from http://www.partnersforcleanwater.org/Annual%20Report.asp. August 2008. City of Boise. 2006-2007. NPDES Municipal Separate Stormwater System Annual Report. Boise, ID. Retrieved from http://www.partnersforcleanwater.org/Annual%20Report.asp. August 2008. -----2005. Lower Boise River Mainstem Tributary Temperature Analysis: Data Summary and Technical Report. Boise City Public Works. 17p. City of Garden City. 2006-2007. NPDES Municipal Separate Stormwater System Annual Report. Boise, ID. Retrieved from http://www.partnersforcleanwater.org/Annual%20Report.asp. August 2008. Clean Water Act (Federal water pollution control act), 33 U.S.C. § 1251-1387. 1972. Cosgrove, D.M., Taylor, J. 2007. Preliminary Assessment of Hydrogeology and Water Quality in Ground Water in Canyon County, Idaho. Idaho Water Resources Research Institute. Technical Report 07-001 for the Idaho Department of Environmental Quality. 29 p. Downing, John. 2005. Turbidity Monitoring. Chapter 24 in: Environmental Instrumentation and Analysis Handbook. John Wiley & Sons, Pages: 511-546. 2005. Environmental Protection Agency (EPA). 2008. TMDLs to Stormwater Permits Handbook, Draft. US EPA, Office of Water. 211 p. -----2007. Options for Expressing Daily Loads in TMDLs, Draft. US EPA, Office of Wetlands, Oceans and Watersheds. 62p. ----- 2004. Final Decision on Use Attainability Analysis of Lower Boise River Tributaries, Docket 58-0102-0101. Retrieved on July 7, 2008 from http://www.deq.idaho.gov/water/data_reports/surface_water/monitoring/standards.cfm#use. ----- 1996. Biological criteria: technical guidance for streams and small rivers. EPA 822-B-96001. U.S. Environmental Protection Agency, Office of Water. Washington, DC. 162 p. Franson, M.A.H., L.S. Clesceri, A.E. Greenberg, and A.D. Eaton, editors. 1998. Standard methods for the examination of water and wastewater, twentieth edition. American Public Health Association. Washington, DC. 1,191 p.

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Grafe, C.S., C.A. Mebane, M.J. McIntyre, D.A. Essig, D.H. Brandt, and D.T. Mosier. 2002. The Idaho Department of Environmental Quality Water Body Assessment Guidance, second edition (WBAG II). Department of Environmental Quality. Boise, ID. 114 p. Hughes, R.M. 1995. Defining acceptable biological status by comparing with reference condition. In: Davis, W.S. and T.P. Simon, editors. Biological assessment and criteria: tools for water resource planning and decision making. CRC Press. Boca Raton, FL. p 31-48. Idaho Association of Soil Conservation Districts (IASCD). 2005. Lower Boise River Watershed Ag Land Inventory-2005. PowerPoint presentation by Scott Koberg. Idaho Code § 39.3611. Development and implementation of total maximum daily load or equivalent processes. Idaho Code § 39.3615. Creation of watershed advisory groups. Idaho Legislature. Treasure Valley Working Group Final Report. 2004. Interim Legislative Committee on Natural Resources. 17p. IDAPA 58.01.02. Idaho water quality standards and wastewater treatment requirements. Idaho Department of Environmental Quality (IDEQ). 2008. Department of Environmental Quality Working Principals and Policies for the 2008 Integrated (303(d)/305(b)) ReportDraft. State of Idaho. Boise, ID. 439 p. ----- 2005. Principals and Policies for the Integrated (303(d)/305(b)) Report. State of Idaho. Boise, ID. 338 p. ----- 1999. Lower Boise River TMDL Subbasin Assessment, Total Maximum Daily Loads. IDEQ, Boise Region. Boise, ID. 472 p. IDEQ, et al. 2003. Implementation Plan for the Lower Boise River Total Maximum Daily Load. Boise, ID. 462 p. IDEQ and Oregon Department of Environmental Quality. 2004. Snake River-Hells Canyon Total Maximum Daily Load. 710p. IDEQ and Lower Boise Watershed Council. 2008. Sediment and Bacteria Allocations Addendum to the Lower Boise River TMDL. Boise, ID. 12 p. IDEQ and Oregon Department of Environmental Quality. 2004. Snake River-Hells Canyon Total Maximum Daily Load. 710p. Idaho Museum of Natural History. 2008. Digital Atlas of Idaho. Retrieved from http://imnh.isu.edu/digitalatlas/index.htm August 2008. Idaho State Department of Agriculture (IDA). 2006. Annual Report. Retrieved from http://www.agri.idaho.gov/Categories/AboutISDA/Documents/annual_reports/annual_report _2006.pdf November 2008. ----- 2004. Retrieved from http://www.agri.idaho.gov/Categories/AboutISDA/Documents/annual_reports/annual_report _2004.pdf November 2008. ----- 2003. Annual Report. Retrieved from http://www.agri.idaho.gov/Categories/AboutISDA/Documents/annual_reports/annual_report _2003.pdf November 2008. ----- 2003. Mill Slough Water Quality Monitoring Report, April through August 2003. IDA Technical Report Summary W-9. 3 p.

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----- 2002. Ground and Surface Water Interaction Related to Nutrients within Mason Creek Agricultural Drain Canyon County, Idaho. 120 p. Idaho State Historical Society (ISHS). 2001. Oregon Trail in Idaho (Fort Boise). Retrieved on August 8, 2008 from http://www.idahohistory.net/OTftboise.html. -----2001. Oregon Trail in Idaho (Canyon Hill). Retrieved on August 8, 2008 from http://www.idahohistory.net/OTcanyon.html. -----1993. Boise River Fisheries. Idaho State Historical Society Reference Series Number 1022. Retrieved on July 15, 2008 from http://www.idahohistory.net/Reference%20Series/1022.pdf. ----- 1993. Fur Trade Activity in Boise Valley. Idaho State Historical Society Reference Series Number 1025. Retrieved on August 8, 2008 from http://www.idahohistory.net/Reference%20Series/1025.pdf. ----- No Date. Trees in Early Boise. Idaho State Historical Society Reference Series Number 31. Retrieved on August 8, 2008 from http://www.idahohistory.net/Reference%20Series/0031.pdf Idaho Transportation Department, District 3. 2006-2007. The Municipal Separate Stormwater Sewer System (MS4) NPDES Permit Annual Report. Retrieved from http://www.partnersforcleanwater.org/Annual%20Report.asp. August 2008. Idaho Water Resources Research Institute (IWWRI). 2004. Treasure Valley Hydrologic Report Executive Summary. IWWRI Research Report IWRRI-2004-04. Prepared for Idaho Department of Water Resources (IDWR). 38p. Karr, J.R. 1991. Biological integrity: a long-neglected aspect of water resource management. Ecological Applications 1:66-84. Koberg, Scott. 2008. Lower Boise TMDL PowerPoint Presentations (CD). Ada Soil and Water Conservation District. Boise, Idaho. Lewis, Jack. 1996. Turbidity -Controlled Suspended Sediment Sampling for Runoff-Event Load Estimation. Water Resources Research Volume 32, No. 7, pp. 2299-2310. Long, Roger B., Zhang, Jinghua. 1996. Economic Causes of Non-Point Pollution in the Boise River. University of Idaho, College of Agriculture. Cooperative Extension System, Bulletin 783. 12 p. Lower Boise River Water Quality Plan (LBRWQP). 2003. Lower Boise River Coliform Bacteria DNA Testing: Final Summary Report. Prepared by CH2MHill, Boise, Idaho. 27 p. MacCoy, D., Blew, D. 2005. Impacts of Land-Use Changes and Hydrologic Modification on the Lower Boise River, Idaho, USA. American Fisheries Society symposium 47:133-156, 2005. 24p. Mullins, William. 1998. Water Quality Conditions of the Lower Boise River, Ada and Canyon Counties, Idaho, May 1994 through February 1997. USGS Water-Resources Investigations Report 98–4111. Boise, ID. 32 p. Newcombe, C.P. and J.O.T. Jensen. 1996. Channel suspended sediment and fisheries: a synthesis for quantitative assessment of risk and impact. North American Journal of Fisheries Management. Volume 16(4): 693-727. Porterfield, George. Computation of fluvial-sediment discharge.1972. USGS TWRI-3-C3. 66 p. Rand, G.W., editor. 1995. Fundamentals of aquatic toxicology: effects, environmental fate, and risk assessment, second edition. Taylor and Francis. Washington, DC. 1,125 p.

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Schmidt, R. D., et. al. 2008. Economic/Hydrologic Externalities and Spatial Water Allocation modeling. Symposium Presentation. Boise Valley Water Use Planning Study. Bureau of Reclamation, University of Idaho, and Idaho Water Resources Research Institute. Boise Idaho. Strahler, A.N. 1957. Quantitative analysis of watershed geomorphology. Transactions American Geophysical Union 38:913-920. United States Army Corps of Engineers (USACE). Lower Boise River and Tributaries, Idaho: Reconnaissance Study. 1995. USACE, Walla Walla District. 283 p. United States Bureau of Reclamation (BOR). 1997. The Boise Project, Second Draft. Bureau of Reclamation History Program. Denver Colorado. ----- 2008. Economic/Hydrologic Externalities of Spatial Water Allocation Modeling (Presentation). The Boise Valley Water Use Planning Study. BOR, IWWRI, and University of Idaho. United States Census Bureau. State and County QuickFacts. 2008. Retrieved May 1, 2008 from http://quickfacts.census.gov/qfd/states/16/16001.html. United States Department of Agriculture (USDA). 1999. A procedure to estimate the response of aquatic systems to changes in phosphorus and nitrogen inputs. National Water and Climate Center, Natural Resources Conservation Service. Portland, OR. United States Department of the Interior (DOI). 2004. Final Environmental Assessment Lucky Peak Water Service Contracts Renewal or Conversion. Bureau of Reclamation (BOR). Pacific Northwest Region, Snake River Area Office. Boise, Idaho. 188p. United States Geological Survey (USGS). Phosphorus and Suspended Sediment Load Estimates for the Lower Boise River, Idaho, 1994 – 2002. 2005. Scientific Investigations Report 20045235. Version 2. 39p. -----2004. Water-Quality and Biological Conditions in the Lower Boise River, Ada and Canyon Counties, Idaho, 1994–2002. Scientific Investigation Report 2004-5128. 90p. ----- 2001. Summary of the U.S. Geological Survey On-line Instantaneous Fluvial Sediment and Ancillary Data. Proceedings of the 7th Federal Interagency Sedimentation Conference, Reno, NV. -----1999. Biological Assessment of the Lower Boise River, October 1995 through January 1998, Ada and Canyon Counties, Idaho. Water Resource Investigations Report 99-4178. 43p. ----- 1987. Hydrologic unit maps. Water supply paper 2294. United States Geological Survey. Denver, CO. 63 p. University of Idaho (U of I). 2005. BMP Handbook Best Management Practices for Idaho

Rural Road Maintenance. Compiled by Stacy Smith. Idaho Technology Transfer (T2) Center. Engineering Physics Building. Moscow, ID. 108p. ----- 2005. The American Dream: Living on the Land—Stewardship for Small Acreages in Idaho! Extension Article 25-05sjensen-land.doc. 2p. Retrieved on December 2, 2008 from http://www.extension.uidaho.edu/impacts/Pdf_05/25-05sjensen-land.pdf. Water Environment Federation. 1987. The Clean Water Act of 1987. Water Environment Federation. Alexandria, VA. 318 p. Water Quality Act of 1987, Public Law 100-4. 1987.

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Water quality planning and management, 40 CFR Part 130. Wetzel, R.G. 1983. Limnology. Saunders College Publishing. New York, NY.

GIS Coverages Restriction of liability: Neither the state of Idaho nor the Department of Environmental Quality, nor any of their employees make any warranty, express or implied, or assume any legal liability or responsibility for the accuracy, completeness or usefulness of any information or data provided. Metadata is provided for all data sets, and no data should be used without first reading and understanding its limitations. The data could include technical inaccuracies or typographical errors. The Department of Environmental Quality may update, modify, or revise the data used at any time, without notice.

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Glossary §303(d) Refers to section 303 subsection “d” of the Clean Water Act. 303(d) requires states to develop a list of water bodies that do not meet water quality standards. This section also requires total maximum daily loads (TMDLs) be prepared for listed waters. Both the list and the TMDLs are subject to U.S. Environmental Protection Agency approval. Anthropogenic Relating to, or resulting from, the influence of human beings on nature. Aquatic Occurring, growing, or living in water. Assemblage (aquatic) An association of interacting populations of organisms in a given water body; for example, a fish assemblage or a benthic macroinvertebrate assemblage (also see Community) (EPA 1996). Assessment Database (ADB) The ADB is a relational database application designed for the U.S. Environmental Protection Agency for tracking water quality assessment data, such as use attainment and causes and sources of impairment. States need to track this information and many other types of assessment data for thousands of water bodies and integrate it into meaningful reports. The ADB is designed to make this process accurate, straightforward, and user-friendly for participating states, territories, tribes, and basin commissions. Assessment Unit (AU) A segment of a water body that is treated as a homogenous unit, meaning that any designated uses, the rating of these uses, and any associated causes and sources must be applied to the entirety of the unit. Beneficial Use Any of the various uses of water, including, but not limited to, aquatic life, recreation, water supply, wildlife habitat, and aesthetics, which are recognized in water quality standards. Beneficial Use Reconnaissance Program (BURP) A program for conducting systematic biological and physical habitat surveys of water bodies in Idaho. BURP protocols address lakes, reservoirs, and wadeable streams and rivers Benthic Pertaining to or living on or in the bottom sediments of a water body Benthic Organic Matter. The organic matter on the bottom of a water body. Best Management Practices (BMPs) Structural, nonstructural, and managerial techniques that are effective and practical means to control nonpoint source pollutants. Biomass

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Biota The animal and plant life of a given region. Biotic A term applied to the living components of an area. Clean Water Act (CWA) The Federal Water Pollution Control Act (commonly known as the Clean Water Act), as last reauthorized by the Water Quality Act of 1987, establishes a process for states to use to develop information on, and control the quality of, the nation’s water resources. Coliform Bacteria A group of bacteria predominantly inhabiting the intestines of humans and animals but also found in soil. Coliform bacteria are commonly used as indicators of the possible presence of pathogenic organisms (also see Fecal Coliform Bacteria, E. coli, and Pathogens). Community A group of interacting organisms living together in a given place. Conductivity The ability of an aqueous solution to carry electric current, expressed in micro (μ) mhos/centimeter at 25 °C. Conductivity is affected by dissolved solids and is used as an indirect measure of total dissolved solids in a water sample. Criteria In the context of water quality, numeric or descriptive factors taken into account in setting standards for various pollutants. These factors are used to determine limits on allowable concentration levels, and to limit the number of violations per year. The U.S. Environmental Protection Agency develops criteria guidance; states establish criteria. Cubic Feet per Second A unit of measure for the rate of flow or discharge of water. One cubic foot per second is the rate of flow of a stream with a cross-section of one square foot flowing at a mean velocity of one foot per second. At a steady rate, once cubic foot per second is equal to 448.8 gallons per minute and 10,984 acre-feet per day. Decomposition The breakdown of organic molecules (e.g., sugar) to inorganic molecules (e.g., carbon dioxide and water) through biological and nonbiological processes. Designated Uses Those water uses identified in state water quality standards that must be achieved and maintained as required under the Clean Water Act. Discharge The amount of water flowing in the stream channel at the time of measurement. Usually expressed as cubic feet per second (cfs). Dissolved Oxygen (DO) The oxygen dissolved in water. Adequate DO is vital to fish and other aquatic life.

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Disturbance Any event or series of events that disrupts ecosystem, community, or population structure and alters the physical environment. E. coli Short for Escherichia coli, E. coli are a group of bacteria that are a subspecies of coliform bacteria. Most E. coli are essential to the healthy life of all warm-blooded animals, including humans, but their presence in water is often indicative of fecal contamination. E. coli are used by the state of Idaho as the indicator for the presence of pathogenic microorganisms. Ecology The scientific study of relationships between organisms and their environment; also defined as the study of the structure and function of nature. Ecological Indicator A characteristic of an ecosystem that is related to, or derived from, a measure of a biotic or abiotic variable that can provide quantitative information on ecological structure and function. An indicator can contribute to a measure of integrity and sustainability. Ecological indicators are often used within the multimetric index framework. Ecological Integrity The condition of an unimpaired ecosystem as measured by combined chemical, physical (including habitat), and biological attributes (EPA 1996). Ecosystem The interacting system of a biological community and its non-living (abiotic) environmental surroundings. Effluent A discharge of untreated, partially treated, or treated wastewater into a receiving water body; or a discharge of water mixed with waste material into a stream. Endangered Species Animals, birds, fish, plants, or other living organisms threatened with imminent extinction. Requirements for declaring a species as endangered are contained in the Endangered Species Act. Environment The complete range of external conditions, physical and biological, that affect a particular organism or community. Ephemeral Stream A stream or portion of a stream that flows only in direct response to precipitation. It receives little or no water from springs and no long continued supply from melting snow or other sources. Its channel is at all times above the water table (American Geological Institute 1962). Erosion The wearing away of areas of the earth’s surface by water, wind, ice, and other forces. Exceedance A violation (according to DEQ policy) of the pollutant levels permitted by water quality criteria.

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Existing Beneficial Use or Existing Use A beneficial use actually attained in waters on or after November 28, 1975, whether or not the use is designated for the waters in Idaho’s Water Quality Standards and Wastewater Treatment Requirements (IDAPA 58.01.02). Exotic Species A species that is not native (indigenous) to a region. Extrapolation Estimation of unknown values by extending or projecting from known values. Fauna Animal life, especially the animals characteristic of a region, period, or special environment. Fecal Coliform Bacteria Bacteria found in the intestinal tracts of all warm-blooded animals or mammals. Their presence in water is an indicator of pollution and possible contamination by pathogens (also see Coliform Bacteria, E. coli, and Pathogens). Feedback Loop In the context of watershed management planning, a feedback loop is a process that provides for tracking progress toward goals and revising actions according to that progress. Flow See Discharge. Fluvial In fisheries, this describes fish whose life history takes place entirely in streams but migrate to smaller streams for spawning. Focal Critical areas supporting a mosaic of high quality habitats that sustain a diverse or unusually productive complement of native species. Fully Supporting In compliance with water quality standards and within the range of biological reference conditions for all designated and exiting beneficial uses as determined through the Water Body Assessment Guidance (Grafe et al. 2002). Fully Supporting Cold Water Reliable data indicate functioning, sustainable cold water biological assemblages (e.g., fish, macroinvertebrates, or algae), none of which have been modified significantly beyond the natural range of reference conditions. Fully Supporting but Threatened An intermediate assessment category describing water bodies that fully support beneficial uses, but have a declining trend in water quality conditions, which if not addressed, will lead to a “not fully supporting” status. Geographical Information Systems (GIS) A georeferenced database.

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Geometric Mean A back-transformed mean of the logarithmically transformed numbers often used to describe highly variable, right-skewed data (a few large values), such as bacterial data. Grab Sample A single sample collected at a particular time and place. It may represent the composition of the water in that water column. Gradient The slope of the land, water, or streambed surface. Ground Water Water found beneath the soil surface saturating the layer in which it is located. Most ground water originates as rainfall, is free to move under the influence of gravity, and usually emerges again as stream flow. Habitat The living place of an organism or community. Headwater The origin or beginning of a stream. Hydrologic Basin The area of land drained by a river system, a reach of a river and its tributaries in that reach, a closed basin, or a group of streams forming a drainage area (also see Watershed). Hydrologic Cycle The cycling of water from the atmosphere to the earth (precipitation) and back to the atmosphere (evaporation and plant transpiration). Atmospheric moisture, clouds, rainfall, runoff, surface water, ground water, and water infiltrated in soils are all part of the hydrologic cycle. Hydrologic Unit One of a nested series of numbered and named watersheds arising from a national standardization of watershed delineation. The initial 1974 effort (USGS 1987) described four levels (region, subregion, accounting unit, and cataloging unit) of watersheds throughout the United States. The fourth level is uniquely identified by an eight-digit code built of two-digit fields for each level in the classification. Originally termed a cataloging unit, fourth field hydrologic units have been more commonly called subbasins. Fifth and sixth field hydrologic units have since been delineated for much of the country and are known as watershed and subwatersheds, respectively. Hydrologic Unit Code (HUC) The number assigned to a hydrologic unit. Often used to refer to fourth field hydrologic units. Hydrology The science dealing with the properties, distribution, and circulation of water. Influent A tributary stream. Inorganic Materials not derived from biological sources.

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Instantaneous A condition or measurement at a moment (instant) in time. Intergravel Dissolved Oxygen The concentration of dissolved oxygen within spawning gravel. Consideration for determining spawning gravel includes species, water depth, velocity, and substrate. Intermittent Stream 1) A stream that flows only part of the year, such as when the ground water table is high or when the stream receives water from springs or from surface sources such as melting snow in mountainous areas. The stream ceases to flow above the streambed when losses from evaporation or seepage exceed the available stream flow. 2) A stream that has a period of zero flow for at least one week during most years. Irrigation Return Flow Surface (and subsurface) water that leaves a field following the application of irrigation water and eventually flows into streams. Load Allocation (LA) A portion of a water body’s load capacity for a given pollutant that is given to a particular nonpoint source (by class, type, or geographic area). Load(ing) The quantity of a substance entering a receiving stream, usually expressed in pounds or kilograms per day or tons per year. Loading is the product of flow (discharge) and concentration. Load(ing) Capacity (LC) A determination of how much pollutant a water body can receive over a given period without causing violations of state water quality standards. Upon allocation to various sources, and a margin of safety, it becomes a total maximum daily load. Macroinvertebrate An invertebrate animal (without a backbone) large enough to be seen without magnification and retained by a 500μm mesh (U.S. #30) screen. Macrophytes Rooted and floating vascular aquatic plants commonly referred to as water weeds. These plants usually flower and bear seeds. Some forms, such as duckweed and coontail (Ceratophyllum sp.), are free-floating forms not rooted in sediment. Margin of Safety (MOS) An implicit or explicit portion of a water body’s loading capacity set aside to allow the uncertainly about the relationship between the pollutant loads and the quality of the receiving water body. This is a required component of a total maximum daily load (TMDL) and is often incorporated into conservative assumptions used to develop the TMDL (generally within the calculations and/or models). The MOS is not allocated to any sources of pollution.

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Mean Describes the central tendency of a set of numbers. The arithmetic mean (calculated by adding all items in a list, then dividing by the number of items) is the statistic most familiar to most people. Median The middle number in a sequence of numbers. If there is an even number of numbers, the median is the average of the two middle numbers. For example, 4 is the median of 1, 2, 4, 14, and 16; 6 is the median of 1, 2, 5, 7, 9, and 11. Metric 1) A discrete measure of something, such as an ecological indicator (e.g., number of distinct taxon). 2) The metric system of measurement. Milligrams per Liter (mg/L) A unit of measure for concentration. In water, it is essentially equivalent to parts per million (ppm). Million Gallons per Day (MGD) A unit of measure for the rate of discharge of water often used to measure flow at wastewater treatment plants. One MGD is equal to 1.547 cubic feet per second. Monitoring A periodic or continuous measurement of the properties or conditions of some medium of interest, such as monitoring a water body. Mouth The location where flowing water enters into a larger water body. National Pollution Discharge Elimination System (NPDES) A national program established by the Clean Water Act for permitting point sources of pollution. Discharge of pollution from point sources is not allowed without a permit. Natural Condition The condition that exists with little or no anthropogenic influence. Nitrogen An element essential to plant growth, and thus is considered a nutrient. Nonpoint Source A dispersed source of pollutants, generated from a geographical area when pollutants are dissolved or suspended in runoff and then delivered into waters of the state. Nonpoint sources are without a discernable point or origin. They include, but are not limited to, irrigated and nonirrigated lands used for grazing, crop production, and silviculture; rural roads; construction and mining sites; log storage or rafting; and recreation sites. Not Assessed (NA) A concept and an assessment category describing water bodies that have been studied, but are missing critical information needed to complete an assessment. Not Attainable A concept and an assessment category describing water bodies that demonstrate characteristics that make it unlikely that a beneficial use

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can be attained (e.g., a stream that is dry but designated for salmonid spawning). Not Fully Supporting Not in compliance with water quality standards or not within the range of biological reference conditions for any beneficial use as determined through the Water Body Assessment Guidance (Grafe et al. 2002). Not Fully Supporting Cold Water At least one biological assemblage has been significantly modified beyond the natural range of its reference condition. Nuisance Anything that is injurious to the public health or an obstruction to the free use, in the customary manner, of any waters of the state. Nutrient Any substance required by living things to grow. An element or its chemical forms essential to life, such as carbon, oxygen, nitrogen, and phosphorus. Commonly refers to those elements in short supply, such as nitrogen and phosphorus, which usually limit growth. Orthophosphate A form of soluble inorganic phosphorus most readily used for algal growth. Parameter A variable, measurable property whose value is a determinant of the characteristics of a system, such as temperature, dissolved oxygen, and fish populations are parameters of a stream or lake. Pathogens A small subset of microorganisms (e.g., certain bacteria, viruses, and protozoa) that can cause sickness or death. Direct measurement of pathogen levels in surface water is difficult. Consequently, indicator bacteria that are often associated with pathogens are assessed. E. coli, a type of fecal coliform bacteria, is used by the state of Idaho as the indicator for the presence of pathogenic microorganisms. Perennial Stream A stream that flows year-around in most years. Periphyton Attached microflora (algae and diatoms) growing on the bottom of a water body or on submerged substrates, including larger plants. Pesticide Substances or mixtures of substances intended for preventing, destroying, repelling, or mitigating any pest. Also, any substance or mixture intended for use as a plant regulator, defoliant, or desiccant. pH The negative log10 of the concentration of hydrogen ions, a measure which in water ranges from very acid (pH=1) to very alkaline (pH=14). A pH of 7 is neutral. Surface waters usually measure between pH 6 and 9. Phased TMDL A total maximum daily load (TMDL) that identifies interim load allocations and details further monitoring to gauge the success of

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management actions in achieving load reduction goals and the effect of actual load reductions on the water quality of a water body. Under a phased TMDL, a refinement of load allocations, wasteload allocations, and the margin of safety is planned at the outset. Phosphorus An element essential to plant growth, often in limited supply, and thus considered a nutrient. Physiochemical In the context of bioassessment, the term is commonly used to mean the physical and chemical factors of the water column that relate to aquatic biota. Examples in bioassessment usage include saturation of dissolved gases, temperature, pH, conductivity, dissolved or suspended solids, forms of nitrogen, and phosphorus. This term is used interchangeable with the term “physical/chemical.” Point Source A source of pollutants characterized by having a discrete conveyance, such as a pipe, ditch, or other identifiable “point” of discharge into receiving water. Common point sources of pollution are industrial and municipal wastewater. Pollutant Generally, any substance introduced into the environment that adversely affects the usefulness of a resource or the health of humans, animals, or ecosystems. Pollution A very broad concept that encompasses human-caused changes in the environment which alter the functioning of natural processes and produce undesirable environmental and health effects. This includes human-induced alteration of the physical, biological, chemical, and radiological integrity of water and other media. Population A group of interbreeding organisms occupying a particular space; the number of humans or other living creatures in a designated area. Protocol A series of formal steps for conducting a test or survey. Qualitative Descriptive of kind, type, or direction. Quality Assurance (QA) A program organized and designed to provide accurate and precise results. Included are the selection of proper technical methods, tests, or laboratory procedures; sample collection and preservation; the selection of limits; data evaluation; quality control; and personnel qualifications and training (Rand 1995). The goal of QA is to assure the data provided are of the quality needed and claimed (EPA 1996). Quality Control (QC) Routine application of specific actions required to provide information for the quality assurance program. Included are standardization, calibration, and replicate samples (Rand 1995). QC is implemented at the field or bench level (EPA 1996).

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Quantitative Descriptive of size, magnitude, or degree. Reach A stream section with fairly homogenous physical characteristics. Reconnaissance An exploratory or preliminary survey of an area. Reference A physical or chemical quantity whose value is known and thus is used to calibrate or standardize instruments. Reference Condition 1) A condition that fully supports applicable beneficial uses with little affects from human activity and represents the highest level of support attainable. 2) A benchmark for populations of aquatic ecosystems used to describe desired conditions in a biological assessment and acceptable or unacceptable departures from them. The reference condition can be determined through examining regional reference sites, historical conditions, quantitative models, and expert judgment (Hughes 1995). Riparian Associated with aquatic (stream, river, lake) habitats. Living or located on the bank of a water body. River A large, natural, or human-modified stream that flows in a defined course or channel or in a series of diverging and converging channels. Runoff The portion of rainfall, melted snow, or irrigation water that flows across the surface, through shallow underground zones (interflow), and through ground water to creates streams. Sediments Deposits of fragmented materials from weathered rocks and organic material that were suspended in, transported by, and eventually deposited by water or air. Settleable Solids The volume of material that settles out of one liter of water in one hour. Species 1) A reproductively isolated aggregate of interbreeding organisms having common attributes and usually designated by a common name. 2) An organism belonging to such a category. Spring Ground water seeping out of the earth where the water table intersects the ground surface. Stenothermal Unable to tolerate a wide temperature range. Stratification A Department of Environmental Quality classification method used to characterize comparable units (also called classes or strata).

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Stream A natural water course containing flowing water, at least part of the year. Together with dissolved and suspended materials, a stream normally supports communities of plants and animals within the channel and the riparian vegetation zone. Stream Order Hierarchical ordering of streams based on the degree of branching. A first-order stream is an unforked or unbranched stream. Under Strahler’s (1957) system, higher order streams result from the joining of two streams of the same order. Storm Water Runoff Rainfall that quickly runs off the land after a storm. In developed watersheds the water flows off roofs and pavement into storm drains that may feed quickly and directly into the stream. The water often carries pollutants picked up from these surfaces. Stressors Physical, chemical, or biological entities that can induce adverse effects on ecosystems or human health. Subbasin A large watershed of several hundred thousand acres. This is the name commonly given to 4th field hydrologic units (also see Hydrologic Unit). Subbasin Assessment (SBA) A watershed-based problem assessment that is the first step in developing a total maximum daily load in Idaho. Subwatershed A smaller watershed area delineated within a larger watershed, often for purposes of describing and managing localized conditions. Also proposed for adoption as the formal name for 6th field hydrologic units. Surface Fines Sediments of small size deposited on the surface of a streambed or lake bottom. The upper size threshold for fine sediment for fisheries purposes varies from 0.8 to 605 millimeters depending on the observer and methodology used. Results are typically expressed as a percentage of observation points with fine sediment. Surface Runoff Precipitation, snow melt, or irrigation water in excess of what can infiltrate the soil surface and be stored in small surface depressions; a major transporter of nonpoint source pollutants in rivers, streams, and lakes. Surface runoff is also called overland flow. Surface Water All water naturally open to the atmosphere (rivers, lakes, reservoirs, streams, impoundments, seas, estuaries, etc.) and all springs, wells, or other collectors that are directly influenced by surface water. Suspended Sediments Fine material (usually sand size or smaller) that remains suspended by turbulence in the water column until deposited in areas of weaker current. These sediments cause turbidity and, when deposited, reduce

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living space within streambed gravels and can cover fish eggs or alevins. Taxon Any formal taxonomic unit or category of organisms (e.g., species, genus, family, order). The plural of taxon is taxa (Armantrout 1998). Threatened Species Species, determined by the U.S. Fish and Wildlife Service, which are likely to become endangered within the foreseeable future throughout all or a significant portion of their range. Total Maximum Daily Load (TMDL) A TMDL is a water body’s load capacity after it has been allocated among pollutant sources. It can be expressed on a time basis other than daily if appropriate. Sediment loads, for example, are often calculated on an annual basis. A TMDL is equal to the load capacity, such that load capacity = margin of safety + natural background + load allocation + wasteload allocation = TMDL. In common usage, a TMDL also refers to the written document that contains the statement of loads and supporting analyses, often incorporating TMDLs for several water bodies and/or pollutants within a given watershed. Total Dissolved Solids Dry weight of all material in solution in a water sample as determined by evaporating and drying filtrate. Total Suspended Solids (TSS) The dry weight of material retained on a filter after filtration. Filter pore size and drying temperature can vary. American Public Health Association Standard Methods (Franson et al. 1998) call for using a filter of 2.0 microns or smaller; a 0.45 micron filter is also often used. This method calls for drying at a temperature of 103-105 °C. Toxic Pollutants Materials that cause death, disease, or birth defects in organisms that ingest or absorb them. The quantities and exposures necessary to cause these effects can vary widely. Tributary A stream feeding into a larger stream or lake. Total Dissolved Solids Dry weight of all material in solution in a water sample as determined by evaporating and drying filtrate. Total Suspended Solids (TSS) The dry weight of material retained on a filter after filtration. Filter pore size and drying temperature can vary. American Public Health Association Standard Methods (Franson et al. 1998) call for using a filter of 2.0 micron or smaller; a 0.45 micron filter is also often used. This method calls for drying at a temperature of 103-105 °C. Tributary A stream feeding into a larger stream or lake. Turbidity A measure of the extent to which light passing through water is scattered by fine suspended materials. The effect of turbidity depends

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on the size of the particles (the finer the particles, the greater the effect per unit weight) and the color of the particles. Wasteload Allocation (WLA) The portion of receiving water’s loading capacity that is allocated to one of its existing or future point sources of pollution. Wasteload allocations specify how much pollutant each point source may release to a water body. Water Body A stream, river, lake, estuary, coastline, or other water feature, or portion thereof. Water Column Water between the interface with the air at the surface and the interface with the sediment layer at the bottom. The idea derives from a vertical series of measurements (oxygen, temperature, phosphorus) used to characterize water. Water Pollution Any alteration of the physical, thermal, chemical, biological, or radioactive properties of any waters of the state, or the discharge of any pollutant into the waters of the state, which will or is likely to create a nuisance or to render such waters harmful, detrimental, or injurious to public health, safety, or welfare; to fish and wildlife; or to domestic, commercial, industrial, recreational, aesthetic, or other beneficial uses. Water Quality A term used to describe the biological, chemical, and physical characteristics of water with respect to its suitability for a beneficial use. Water Quality Criteria Levels of water quality expected to render a body of water suitable for its designated uses. Criteria are based on specific levels of pollutants that would make the water harmful if used for drinking, swimming, farming, or industrial processes. Water Quality Management Plan A state or area-wide waste treatment management plan developed and updated in accordance with the provisions of the Clean Water Act. Water Quality Modeling The prediction of the response of some characteristics of lake or stream water based on mathematical relations of input variables such as climate, stream flow, and inflow water quality. Water Quality Standards State-adopted and U.S. Environmental Protection Agency-approved ambient standards for water bodies. The standards prescribe the use of the water body and establish the water quality criteria that must be met to protect designated uses. Water Table The upper surface of ground water; below this point, the soil is saturated with water. Watershed 1) All the land which contributes runoff to a common point in a drainage network, or to a lake outlet. Watersheds are infinitely nested,

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and any large watershed is composed of smaller “subwatersheds.” 2) The whole geographic region which contributes water to a point of interest in a water body. Water Body Identification Number (WBID) A number that uniquely identifies a water body in Idaho and ties in to the Idaho water quality standards and GIS information. Wetland An area that is at least some of the time saturated by surface or ground water so as to support with vegetation adapted to saturated soil conditions. Examples include swamps, bogs, fens, and marshes.

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Appendix A. Unit Conversion Chart

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Table A-1. Metric - English unit conversions. Distance Length

Area

Volume

Flow Rate

English Units

Metric Units

Miles (mi)

Kilometers (km)

To Convert

Cubic Feet per Second (cfs)a

Cubic Meters per Second (m3/sec)

1 1 Inches (in) Centimeters (cm) 1 Feet (ft) Meters (m) 1 1 1 Acres (ac) Hectares (ha) 1 2 2 Square Feet (ft ) Square Meters (m ) 1 Square Miles (mi2) Square Kilometers (km2) 1 1 1 1 Gallons (gal) Liters (L) 1 Cubic Feet (ft3) Cubic Meters (m3) 1 1 1

Concentration Parts per Million Milligrams per Liter Weight

(ppm) Pounds (lbs)

(mg/L) Kilograms (kg)

Temperature

Fahrenheit (°F)

Celsius (°C)

a b

1 cfs = 0.65 million gallons per day; 1 million gallons per day is equal to 1.55 cfs. The ratio of 1 ppm = 1 mg/L is approximate and is only accurate for water.

132

mi = 1.61 km km = 0.62 mi in = 2.54 cm cm = 0.39 in ft = 0.30 m m = 3.28 ft ac = 0.40 ha ha = 2.47 ac ft2 = 0.09 m2 m2 = 10.76 ft2 mi2 = 2.59 km2 km2 = 0.39 mi2 gal = 3.78 L L= 0.26 gal ft3 = 0.03 m3 m3 = 35.32 ft3

1 cfs = 0.03 m3/sec 1 m3/sec = 35.31 cfs 1 ppm = 1 mg/Lb 1 lb 1 kg °C = 32) °F = + 32

Example

3 mi = 4.83 km 3 km = 1.86 mi 3 in = 7.62 cm 3 cm = 1.18 in 3 ft = 0.91 m 3 m = 9.84 ft 3 ac = 1.20 ha 3 ha = 7.41 ac 3 ft2 = 0.28 m2 3 m2 = 32.29 ft2 3 mi2 = 7.77 km2 3 km2 = 1.16 mi2 3 gal = 11.35 L 3 L = 0.79 gal 3 ft3 = 0.09 m3 3 m3 = 105.94 ft3 3 ft3/sec = 0.09 m3/sec 3 m3/sec = 105.94 ft3/sec 3 ppm = 3 mg/L

= 0.45 kg 3 lb = = 2.20 lbs 3 kg = 0.55 (F - 3 °F = °C (C x 1.8) 3 °C =

1.36 kg 6.61 lb -15.95 37.4 °F

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Appendix B. State and Site-Specific Standards and Criteria

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IDAPA 58 TITLE 01 CHAPTER 02 58.01.02 - WATER QUALITY STANDARDS 056.SPECIAL RESOURCE WATERS. 01. Designations. Waters of the state may be designated as special resource waters. Designation as a special resource water recognizes at least one (1) of the following characteristics: (7-1-93) a. The water is of outstanding high quality, exceeding both criteria for primary contact recreation and cold water aquatic life; (4-5-00) b. The water is of unique ecological significance; (7-1-93) c. The water possesses outstanding recreational or aesthetic qualities; (7-1-93) d. Intensive protection of the quality of the water is in paramount interest of the people of Idaho; (7-1-93) e. The water is a part of the National Wild and Scenic River System, is within a State or National Park or wildlife refuge and is of prime or major importance to that park or refuge; or (4-5-00) f. Intensive protection of the quality of the water is necessary to maintain an existing, but jeopardized beneficial use. (4-5-00) 02. Designated Waters. Those waters of the state determined to be special resource waters are listed in Sections 110 through 160. (4-5-00) 03. Restrictions of Point Source Discharges to Special Resource Waters and Their Tributaries. Point source discharges to special resource waters and their tributaries shall be restricted as specified in Subsection 400.01.b. 100.SURFACE WATER USE DESIGNATIONS. Waterbodies are designated in Idaho to protect water quality for existing or designated uses. The designated use of a waterbody does not imply any rights to access or ability to conduct any activity related to the use designation, nor does it imply that an activity is safe. For example, a designation of primary or secondary contact recreation may occur in areas where it is unsafe to enter the water due to water flows, depth or other hazardous conditions. Another example is that aquatic life uses may be designated in areas that are closed to fishing or access is not allowed by property owners. Wherever attainable, the designated beneficial uses for which the surface waters of the state are to be protected include: (3-15-02) 01. Aquatic Life. (7-1-93) a. Cold water (COLD): water quality appropriate for the protection and maintenance of a viable aquatic life community for cold water species. (4-5-00) b. Salmonid spawning (SS): waters which provide or could provide a habitat for active self-propagating populations of salmonid fishes. (3-30-07) c. Seasonal cold water (SC): water quality appropriate for the protection and maintenance of a viable aquatic life community of cool and cold water species, where cold water aquatic life may be absent during, or tolerant of, seasonally warm temperatures. (4-5-00) d. Warm water (WARM): water quality appropriate for the protection and maintenance of a viable aquatic life community for warm water species. (4-5-00) e. Modified (MOD): water quality appropriate for an aquatic life community that is limited due to one (1) or more conditions set forth in 40 CFR 131.10(g) which preclude attainment of reference streams or conditions. (4-5-00)

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02. Recreation. (7-1-93) a. Primary contact recreation (PCR): water quality appropriate for prolonged and intimate contact by humans or for recreational activities when the ingestion of small quantities of water is likely to occur. Such activities include, but are not restricted to, those used for swimming, water skiing, or skin diving. (4-5-00) b. Secondary contact recreation (SCR): water quality appropriate for recreational uses on or about the water and which are not included in the primary contact category. These activities may include fishing, boating, wading, infrequent swimming, and other activities where ingestion of raw water is not likely to occur. (4-5-00) 03. Water Supply. (7-1-93) a. Domestic: water quality appropriate for drinking water supplies. (4-5-00) b. Agricultural: water quality appropriate for the irrigation of crops or as drinking water for livestock. This use applies to all surface waters of the state. (4-5-00) c. Industrial: water quality appropriate for industrial water supplies. This use applies to all surface waters of the state. 101.NONDESIGNATED SURFACE WATERS. 01. Undesignated Surface Waters. Surface waters not designated in Sections 110 through 160 shall be designated according to Section 39-3604, Idaho Code, taking into consideration the use of the surface water and such physical, geological, chemical, and biological measures as may affect the surface water. Prior to designation, undesignated waters shall be protected for beneficial uses, which includes all recreational use in and on the water and the protection and propagation of fish, shellfish, and wildlife, wherever attainable. (3-23-98) a. Because the Department presumes most waters in the state will support cold water aquatic life and primary or secondary contact recreation beneficial uses, the Department will apply cold water aquatic life and primary or secondary contact recreation criteria to undesignated waters unless Sections 101.01.b and 101.01c. are followed. (4-5-00) b. During the review of any new or existing activity on an undesignated water, the Department may examine all relevant data or may require the gathering of relevant data on beneficial uses; pending determination in Section 101.01.c. existing activities will be allowed to continue. (3-23-98) c. If, after review and public notice of relevant data, it is determined that beneficial uses in addition to or other than cold water aquatic life and primary or secondary contact recreation are appropriate, then the Department will: (4-5-00) i. Complete the review and compliance determination of the activity in context with the new information on beneficial uses, and (3-23-98) ii. Initiate rulemaking necessary to designate the undesignated water, including providing all necessary data and information to support the proposed designation. 109.HUC INDEX AND ABBREVIATIONS FOR SECTIONS 110, 120, 130, 140, 150, AND 160. 03. Abbreviations. (4-5-00) a. COLD -- Cold Water Communities. (4-5-00) b. SS -- Salmonid Spawning. (4-5-00) c. SC -- Seasonal Cold Water Communities. (4-5-00) d. WARM -- Warm Water Communities. (4-5-00) e. MOD -- Modified Communities. (4-5-00) f. PCR -- Primary Contact Recreation. (4-5-00) g. SCR -- Secondary Contact Recreation. (4-5-00) h. DWS -- Domestic Water Supply. (4-5-00) i. SRW -- Special Resource Water. (4-5-00) j. NONE -- Use Unattainable. (4-5-00) k. No entry in the Aquatic Life or Recreation columns -- nondesignated waters for those uses. (3-15-02)

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140.SOUTHWEST IDAHO BASIN. Surface waters found within the Southwest basin total nineteen (19) subbasins and are designated as follows: (4-5-00)

12. LOWER BOISE RIVER SUBBASIN, HUC 17050114 . Assessment Waters Unit

Recreation Aquatic Other Life

SW-1 SW-2

PCR SCR

COLD COLD

SCR

SS

SW-3a

SW-3b SW-3c SW-3d SW-5 SW-6 SW-7 SW-8 SW-9 SW-10 SW-11a SW-11b SW-12 SW-13 SW-14 SW-15 SW-16 SW-17

Boise River - to mouth Indian Creek Indian Creek - Sugar Ave. (T03N, R02W, Sec. 15) to mouth Split between New York Canal and historic creek bed to Sugar Ave. (T03N, R02W, Sec. 15) COLD Indian Creek Reservoir to split between New York Canal and historic creek bed MOD Indian Creek Reservoir Indian Creek - source to Indian Creek Reservoir Boise River - river mile 50 (T04N, R02W, Sec. 32) to Indian Creek Mason Creek - New York Canal to mouth Fifteenmile Creek - Miller Canal to mouth Tenmile Creek - Blacks Creek Reservoir Dam to Miller Canal Blacks Creek - source to and including Blacks Creek Reservoir Fivemile Creek - source to Miller Canal Boise River - Diversion Dam to river mile 50 (T04N, R02W, Sec. 32) Boise River - Lucky Peak Dam to Diversion Dam Stewart Gulch, Cottonwood and Crane Creeks source to mouth Dry Creek - source to mouth Big/Little Gulch Creek complex Willow Creek - source to mouth Langley/Graveyard Gulch complex Sand Hollow Creek - source to mouth

SCR PCR SCR PCR

WARM SC COLD, SS

SCR SCR SCR

MOD MOD MOD

SCR PCR

MOD COLD, SS

PCR

COLD

SCR

MOD

DWS SRW DWS SRW

200.GENERAL SURFACE WATER QUALITY CRITERIA. The following general water quality criteria apply to all surface waters of the state, in addition to the water quality criteria set forth for specifically designated waters. (4-5-00)

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01. Hazardous Materials. Surface waters of the state shall be free from hazardous materials in concentrations found to be of public health significance or to impair designated beneficial uses. These materials do not include suspended sediment produced as a result of nonpoint source activities. (8-24-94) 02. Toxic Substances. Surface waters of the state shall be free from toxic substances in concentrations that impair designated beneficial uses. These substances do not include suspended sediment produced as a result of nonpoint source activities. (8-24-94) 03. Deleterious Materials. Surface waters of the state shall be free from deleterious materials in concentrations that impair designated beneficial uses. These materials do not include suspended sediment produced as a result of nonpoint source activities. (8-24-94) 04. Radioactive Materials. (7-1-93) a. Radioactive materials or radioactivity shall not exceed the values listed in the Code of Federal Regulations, Title 10, Chapter 1, Part 20, Appendix B, Table 2, Effluent Concentrations, Column 2. (8-24-94) b. Radioactive materials or radioactivity shall not exceed concentrations required to meet the standards set forth in Title 10, Chapter 1, Part 20, of the Code of Federal Regulations for maximum exposure of critical human organs in the case of foodstuffs harvested from these waters for human consumption. (7-1-93) 05. Floating, Suspended or Submerged Matter. Surface waters of the state shall be free from floating, suspended, or submerged matter of any kind in concentrations causing nuisance or objectionable conditions or that may impair designated beneficial uses. This matter does not include suspended sediment produced as a result of nonpoint source activities. (8-24-94) 06. Excess Nutrients. Surface waters of the state shall be free from excess nutrients that can cause visible slime growths or other nuisance aquatic growths impairing designated beneficial uses. (8-24-94) 07. Oxygen-Demanding Materials. Surface waters of the state shall be free from oxygen-demanding materials in concentrations that would result in an anaerobic water condition. (7-1-93) 08. Sediment. Sediment shall not exceed quantities specified in Sections 250 and 252, or, in the absence of specific sediment criteria, quantities which impair designated beneficial uses. Determinations of impairment shall be based on water quality monitoring and surveillance and the information utilized as described in Section 350. (4-5-00) 09. Natural Background Conditions as Criteria. When natural background conditions exceed any applicable water quality criteria set forth in Sections 210, 250, 251, 252, or 253, the applicable water quality criteria shall not apply; instead, there shall be no lowering of water quality from natural background conditions. Provided, however, that temperature may be increased above natural background conditions when allowed under Section 401. (3-30-07) 250.SURFACE WATER QUALITY CRITERIA FOR AQUATIC LIFE USE DESIGNATIONS. 01. General Criteria. The following criteria apply to all aquatic life use designations. Surface waters are not to vary from the following characteristics due to human activities: (3-15-02) a. Hydrogen Ion Concentration (pH) values within the range of six point five (6.5) to nine point zero (9.0); (3-30-01) b. The total concentration of dissolved gas not exceeding one hundred and ten percent (110%) of saturation at atmospheric pressure at the point of sample collection; (7-1-93) 02. Cold Water. Waters designated for cold water aquatic life are not to vary from the following characteristics due to human activities: (3-15-02) a. Dissolved Oxygen Concentrations exceeding six (6) mg/l at all times. In lakes and reservoirs this standard does not apply to: (7-1-93) i. The bottom twenty percent (20%) of water depth in natural lakes and reservoirs where depths are thirty-five (35) meters or less. (7-1-93) ii. The bottom seven (7) meters of water depth in natural lakes and reservoirs where depths are greater than thirty-five (35) meters. (7-1-93) iii. Those waters of the hypolimnion in stratified lakes and reservoirs. (7-1-93) b. Water temperatures of twenty-two (22) degrees C or less with a maximum daily average of no greater than nineteen (19) degrees C. (8-24-94) c. Temperature in lakes shall have no measurable change from natural background conditions. Reservoirs with mean detention times of greater than fifteen (15) days are considered lakes for this purpose.(3-15-02) d. Ammonia. The following criteria are not to be exceeded dependent upon the temperature, T (degrees C), and pH of the water body: (3-15-02)

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i. Acute Criterion (Criterion Maximum Concentration (CMC)). The one (1) hour average concentration of total ammonia nitrogen (in mg N/L) is not to exceed, more than once every three (3) years, the value calculated using the following equation: (3-15-02)

ii. Chronic Criterion (Criterion Continuous Concentration (CCC)). (3-15-02) (1) The thirty (30) day average concentration of total ammonia nitrogen (in mg N/L) is not to exceed, more than once every three (3) years, the value calculated using the following equations: (3-15-02) (a) When fish early life stages are likely present:

(b) When fish early life stages are likely absent:

(2) The highest four-day (4) average within the thirty-day (30) period should not exceed two point five (2.5) times the CCC. (3-15-02) (3) Because the Department presumes that many waters in the state may have both spring-spawning and fall-spawning species of fish present, early life stages of fish may be present throughout much of the year. Accordingly, the Department will apply the CCC for when fish early life stages are present at all times of the year unless: (3-15-02) (a) Time frames during the year are identified when early life stages are unlikely to be present, and (3-15-02) (b) The Department is provided all readily available information supporting this finding such as the fish species distributions, spawning periods, nursery periods, and the duration of early life stages found in the water body; and (3-15-02) (c) The Department determines early life stages are likely absent. (3-15-02) e. Turbidity, below any applicable mixing zone set by the Department, shall not exceed background turbidity by more than fifty (50) NTU instantaneously or more than twenty-five (25) NTU for more than ten (10) consecutive days. (8-24-94)

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f. Salmonid Spawning. The Department shall determine spawning periods on a waterbody specific basis taking into account knowledge of local fisheries biologists, published literature, records of the Idaho Department of Fish and Game, and other appropriate records of spawning and incubation, as further described in the current version of the “Water Body Assessment Guidance” published by the Idaho Department of Environmental Quality. Waters designated for salmonid spawning, in areas used for spawning and during the time spawning and incubation occurs, are not to vary from the following characteristics due to human activities: (3-30-07) i. Dissolved Oxygen. (8-24-94) (1) Intergravel Dissolved Oxygen. (8-24-94) (a) One (1) day minimum of not less than five point zero (5.0) mg/l. (8-24-94) (b) Seven (7) day average mean of not less than six point zero (6.0) mg/l. (8-24-94) (2) Water-Column Dissolved Oxygen. (8-24-94) (a) One (1) day minimum of not less than six point zero (6.0) mg/l or ninety percent (90%) of saturation, whichever is greater. (8-24-94) ii. Water temperatures of thirteen (13) degrees C or less with a maximum daily average no greater than nine (9) degrees C. (8-24-94) g. Bull Trout Temperature Criteria. Water temperatures for the waters identified under Subsection 250.02.g.i. shall not exceed thirteen degrees Celsius (13C) maximum weekly maximum temperature (MWMT) during June, July and August for juvenile bull trout rearing, and nine degrees Celsius (9C) daily average during September and October for bull trout spawning. For the purposes of measuring these criteria, the values shall be generated from a recording device with a minimum of six (6) evenly spaced measurements in a twenty-four (24) hour period. The MWMT is the mean of daily maximum water temperatures measured over the annual warmest consecutive seven (7) day period occurring during a given year. (3-30-01) i The bull trout temperature criteria shall apply to all tributary waters, not including fifth order main stem rivers, located within areas above fourteen hundred (1400) meters elevation south of the Salmon River basin- Clearwater River basin divide, and above six hundred (600) meters elevation north of the Salmon River basin- Clearwater River basin divide, in the fifty-nine (59) Key Watersheds listed in Table 6, Appendix F of Governor Batt’s State of Idaho Bull Trout Conservation Plan, 1996, or as designated under Sections 110 through 160 of this rule. (3-23-98) ii. No thermal discharges will be permitted to the waters described under Subsection 250.02.g.i. unless socially and economically justified as determined by the Department, and then only if the resultant increase in stream temperature is less than five-tenths degrees Celsius (0.5C). 03. Seasonal Cold Water. Between the summer solstice and autumn equinox, waters designated for seasonal cold water aquatic life are not to vary from the following characteristics due to human activities. For the period from autumn equinox to summer solstice the cold water criteria will apply: (3-15-02) a. Dissolved Oxygen Concentrations exceeding six (6) mg/l at all times. In lakes and reservoirs this standard does not apply to: (4-5-00) i. The bottom twenty percent (20%) of water depth in natural lakes and reservoirs where depths are thirty-five (35) meters or less. (4-5-00) ii. The bottom seven (7) meters of water depth in natural lakes and reservoirs where depths are greater than thirty-five (35) meters. (4-5-00) iii. Those waters of the hypolimnion in stratified lakes and reservoirs. (4-5-00) b. Water temperatures of twenty-six (26) degrees C or less as a daily maximum with a daily average of no greater than twenty-three (23) degrees C. (330-01)

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c. Temperature in lakes shall have no measurable change from natural background conditions. Reservoirs with mean detention times of greater than fifteen (15) days are considered lakes for this purpose.(3-15-02) d. Ammonia. Concentration of ammonia are not to exceed the criteria defined at Subsection 250.02.d. (3-15-02) 04. Warm Water. Waters designated for warm water aquatic life are not to vary from the following characteristics due to human activities: (3-30-07) a. Dissolved oxygen concentrations exceeding five (5) mg/l at all times. In lakes and reservoirs this standard does not apply to: (7-1-93) i. The bottom twenty percent (20%) of the water depth in natural lakes and reservoirs where depths are thirty-five (35) meters or less. (7-1-93) ii. The bottom seven (7) meters of water depth in natural lakes and reservoirs where depths are greater than thirty-five (35) meters. (7-1-93) iii. Those waters of the hypolimnion in stratified lakes and reservoirs. (7-1-93) b. Water temperatures of thirty-three (33) degrees C or less with a maximum daily average not greater than twenty-nine (29) degrees C. (8-24-94) c. Temperature in lakes shall have no measurable change from natural background conditions. Reservoirs with mean detention times of greater than fifteen (15) days are considered lakes for this purpose.(3-15-02) d. Ammonia. The following criteria are to be met dependent upon the temperature, T (degrees C), and pH of the water body: (3-15-02) i. Acute Criterion (Criterion Maximum Concentration (CMC)). The one (1) hour average concentration of total ammonia nitrogen (in mg N/L) is not to exceed, more than once every three (3) years, the value calculated using the following equation:

ii. Chronic Criterion (Criterion Continuous Concentration (CCC)). Concentrations of ammonia are not to exceed the criteria defined at Subsection 250.02.d.ii. (3-15-02) 05. Modified. Water quality criteria for modified aquatic life will be determined on a case-by-case basis reflecting the chemical, physical, and biological levels necessary to attain the existing aquatic life community. These criteria, when determined, will be adopted into these rules. (3-15-02) 251.SURFACE WATER QUALITY CRITERIA FOR RECREATION USE DESIGNATIONS. 01. E. Coli Bacteria. Waters designated for recreation are not to contain E. coli bacteria, used as indicators of human pathogens, in concentrations exceeding: (411-06) a. Geometric Mean Criterion. Waters designated for primary or secondary contact recreation are not to contain E. coli bacteria in concentrations exceeding a geometric mean of one hundred twenty-six (126) E. coli organisms per one hundred (100) ml based on a minimum of five (5) samples taken every three (3) to seven (7) days over a thirty (30) day period. (4-11-06) b. Use of Single Sample Values. A water sample exceeding the E. coli single sample maximums below indicates likely exceedance of the geometric mean criterion, but is not alone a violation of water quality standards. If a single sample exceeds the maximums set forth in Subsections 251.01.b.i., 251.01.b.ii., and 251.01.b.iii., then additional samples must be taken as specified in Subsection 251.01.c.: (4-11-06) i. For waters designated as secondary contact recreation, a single sample maximum of five hundred seventy-six (576) E. coli organisms per one hundred (100) ml; or (4-11-06) ii. For waters designated as primary contact recreation, a single sample maximum of four hundred six (406) E. coli organisms per one hundred (100) ml; or (4-11-06)

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iii. For areas within waters designated for primary contact recreation that are additionally specified as public swimming beaches, a single sample maximum of two hundred thirty-five (235) E. coli organisms per one hundred (100) ml. Single sample counts above this value should be used in considering beach closures. (4-11-06) c. Additional Sampling. When a single sample maximum, as set forth in Subsections 251.01.b.i., 251.01.b.ii., and 251.01.b.iii., is exceeded, additional samples should be taken to assess compliance with the geometric mean E. coli criteria in Subsection 251.01.a. Sufficient additional samples should be taken by the Department to calculate a geometric mean in accordance with Subsection 251.01.a. This provision does not require additional ambient monitoring responsibilities for dischargers. (4-11-06) 252.SURFACE WATER QUALITY CRITERIA FOR WATER SUPPLY USE DESIGNATION. 01. Domestic. Waters designated for domestic water supplies are to exhibit the following characteristics: (4-5-00) a. Radioactive materials or radioactivity not to exceed concentrations specified in Idaho Department of Environmental Quality Rules, IDAPA 58.01.08, “Rules Governing Public Drinking Water Systems.” (8-24-94) b. Small public water supplies (Surface Water). (8-24-94) i. The following Table identifies waters, including their watersheds above the public water supply intake (except where noted), which are designated as small public water supplies. 278. SUBSECTION 150.12. 01. Boise River, SW-1 and SW-5 -- Salmonid Spawning and Dissolved Oxygen. The waters of the Boise River from Veterans State Park to its mouth will have dissolved oxygen concentrations of six (6) mg/l or seventy-five percent (75%) of saturation, whichever is greater, during the spawning period of salmonid fishes inhabiting those waters. (3-15-02) 02. Indian Creek, SW-3b, Mason Creek, SW-6, and Sand Hollow Creek, SW-17 -- Modified Aquatic Life Use. All numeric criteria applicable to the seasonal cold water aquatic life use apply with the exception of dissolved oxygen. Dissolved oxygen concentrations are to exceed four (4) mg/l at all times. (315-02) 03. Fifteenmile Creek, SW-7; Tenmile Creek, SW-8, and Five Mile Creek, SW-10 – Modified Aquatic Life Use. All numeric criteria applicable to the seasonal cold water aquatic life use apply. (3-15-02) 04. Boise River, SW-5 and SW-11a -- Copper and Lead Aquatic Life Criteria. The water-effect ratio (WER) values used in the equations in Subsection 210.02 for calculating copper and lead CMC and CCC values shall be two and five hundred seventy-eight thousandths (2.578) for dissolved copper and two and forty-nine thousandths (2.049) for lead. These site-specific criteria shall apply to the Boise River from the Lander St. wastewater outfall to where the channels of the Boise River become fully mixed downstream of Eagle Island.(5-3-03)

141

Lower Boise River 5-year Subbasin Assessment and TMDL Review

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142

February 2009

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Appendix C. Data Tables and Graphs

143

February 2009

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table C-1. USGS data from Lower Boise River subbasin locations between 2003 and 2008. USGS Reported Data, Lower Boise River Locations, 2003-2007

Site ID

Date

DO WT AT Q SpC DO (% AmmDis. TP OPDis. SSC SSQ E. coli Time (*C) (*C) (cfs) (uS/cm3) (mg/L) sat.) pH (N mg/L) (mg/L) (mg/L) (cfu/100mL) (mg/L) (tons/day)

Boise River below Diversion 13203510 13203510 2/18/2003 12:35 3.5 7 242 13203510 4/15/2003 12:28 6.1 5.5 1200 13203510 5/13/2003 10:48 7.7 12 1570 13203510 6/17/2003 10:30 11.1 25 2110 13203510 7/15/2003 10:32 13.3 25 2030 13203510 8/12/2003 10:34 17 21.5 1960 13203510 9/16/2003 10:02 17.2 16 1360 13203510 10/21/2003 11:27 12.5 20 290 13203510 12/16/2003 10:39 4.6 1.5 240 13203510 2/18/2004 10:32 1.8 11.5 367 13203510 4/14/2004 12:23 5.7 15 1440 13203510 5/12/2004 11:11 8.4 12 1810 13203510 6/15/2004 10:10 10.8 12 1750 13203510 7/20/2004 11:48 13.7 28 2050 13203510 8/24/2004 10:18 16.6 17 1530 13203510 9/21/2004 10:53 16.9 8 1300 13203510 11/7/2005 9:45 10.6 9.5 252 13203510 12/20/2005 14:30 2.4 250 13203510 2/14/2006 12:45 2 4000 13203510 4/18/2006 9:00 5.8 6580 13203510 5/16/2006 8:15 9 8140 13203510 6/13/2006 8:15 9.5 5770

93 92 81 69 51 67 81 92 92 97 96 76 67 70 70 78 90 89 91 73 66 54

12.6 13.1 11.7 11.8 10.3 10 9.3 11.6 13.3 13 13.6 12.5 10.7 9.1 7.5 8.2 10.9 14.2 13.7 17 12.9 12.5

105 117 108 119 109 115 109 119 113 104 121 119 106 97 86 93 110 114 110 148 124 122

144

7.5 7.9 7.8 7.6 7.4 7.5 7.4 7.7 8 7.6 7.6 7.5 7.3 7.2 7 7.3 7.8 7.5 7.1

0.039 0.039 0.039 0.039 0.039 0.039 0.039 0.039 0.039 0.039 0.039 0.039 0.039 0.039 0.03 0.039 0.039

0.02 0.03 0.039 0.039 0.039 0.039 0.02 0.06 0.03 0.03 0.03 0.02 0.039 0.039 0.039 0.02 0.02 0.03 0.02 0.06 0.01 0.02

0.019 0.019 0.019 0.019 0.019 0.019 0.01 0.01 0.01 0.01 0.01 0.01 0.019 0.019 0.019 0.019

0.9 0.9 0.9 4 1 1 2 1 0.9 0.9 0.9 0.9 1 1 4 1 1 2 0.9 6 0.9 0.9

2 10 3 3 4 2 10 45 6 2 10 4 2 3 3 4 3 3 3 18 4 7

1.3 32 13 17 22 11 37 35 3.9 2 39 20 9.5 17 12 14 2 2 32 320 88 109

Lower Boise River 5-year Subbasin Assessment and TMDL Review

DO WT AT Q SpC DO (% (*C) (*C) (cfs) (uS/cm3) (mg/L) sat.) 11.5 2130 51 11.7 120 15.2 2120 59 9.4 104 16.6 1480 60 7 80 12.6 364 66 8.5 88 2.9 250 79 14.3 116 1.5 255 83 14.3 113 5.1 1260 81 10.6 92 7.6 1820 81 10.4 97 11.3 2180 66 9.7 98

Site ID Date Time 13203510 7/11/2006 7:40 13203510 8/22/2006 10:05 13203510 9/12/2006 14:30 13203510 10/18/2006 9:30 13203510 12/20/2006 11:00 13203510 2/21/2007 9:40 13203510 4/11/2007 10:20 13203510 5/16/2007 9:00 13203510 6/20/2007 7:50 13203510 6/26/2007 10:00 13203510 7/18/2007 7:50 13.7 13203510 8/8/2007 9:50 15.4 13203510 9/19/2007 10:00 16.4 13203510 11/19/2007 12:45 8.7 13203510 1/8/2008 9:40 1.8 13203510 3/18/2008 8:45 3

4360 1930 740 245 250 252

72 70 78 88 85 93

9.3 8.9 7.9 11.6 11.9 12.8

101 98 90 111 95 91

February 2009

AmmDis. TP OPDis. SSC SSQ E. coli pH (N mg/L) (mg/L) (mg/L) (cfu/100mL) (mg/L) (tons/day) 0.01 1 3 17 0.01 0.9 3 17 0.01 0.9 2 8 0.01 1 0.02 0.9 0.019 0.9 7.7 0.02 1 9 35 6.8 0.019 0.9 2 9.8 6.5 0.01 1 4 24 0.019 0.007 0.019 1 2 24 6 0.01 1 2 10 7.1 0.02 0.9 1 2 7.2 0.02 0.9 7 0.02 0.9 7.2 0.019 0.9

Sewer outflow at Boise 13205643 13205643

6/27/2007 17:00

13206000 13206000 13206000 13206000 13206000 13206000 13206000

2/18/2003 4/15/2003 5/13/2003 6/17/2003 7/15/2003 8/12/2003 9/16/2003

0.394

5.26

Boise River at Glenwood Bridge 13206000 16:00 16:36 14:33 14:25 14:32 14:15 14:00

6.6 9.5 298 10.2 15 818 11.2 19.5 882 14.6 32 1270 16.6 34 1290 19 29 1300 17.9 19 700

152 114 102 85 68 85 110

13.4 13.4 13.5 13.1 10.9 11.6 10.3

120 132 134 143 123 137 121

145

8.4 8.9 9.1 9 8.6 8.8 8.2

0.039 0.07 0.039 0.039 0.039 0.039 0.039

0.31 0.08 0.12 0.08 0.12 0.11 0.17

0.24 0.05 0.1 0.07 0.1 0.09 0.15

12 19 6 25 11 18 19

5 11 3 6 5 3 8

4 24 7.1 21 17 11 15

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Site ID 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000 13206000

Date 10/21/2003 12/16/2003 2/18/2004 4/14/2004 5/12/2004 6/15/2004 7/20/2004 8/24/2004 9/21/2004 11/7/2005 12/20/2005 2/14/2006 4/18/2006 5/16/2006 6/13/2006 7/11/2006 8/22/2006 9/13/2006 10/17/2006 12/19/2006 2/20/2007 4/10/2007 5/15/2007 6/19/2007 6/26/2007 7/17/2007 8/7/2007 9/18/2007

WT (*C) 15.1 5.2 5.7 8.5 10.9 14.3 17.5 17.6 17.2 10.7 3.2 1.7 6.3 9.4 10.2 12.3 14.8 18 12.2 1.8 4.3 6.7 9.9 13

Time 14:34 14:07 14:26 15:46 15:08 14:34 15:27 14:28 14:49 12:25 12:50 10:15 11:35 10:30 10:35 9:40 8:10 15:15 12:30 13:30 13:00 13:10 12:40 12:30 11:45 12:00 15.6 12:50 16.8 13:00 15.5

DO AT Q SpC DO (% (*C) (cfs) (uS/cm3) (mg/L) sat.) 24 315 159 12.2 132 7 263 169 14.3 123 9.5 385 166 13 114 16 908 120 14.6 138 15 908 100 13.6 136 23 895 91 12.6 135 31 1220 87 10.4 119 21 769 96 10.6 123 16.5 615 108 10.4 118 10.5 282 145 11 111 258 165 14.2 115 4070 97 13.4 105 10 5800 79 14.3 125 6900 70 11.6 111 4330 59 11.7 115 1300 65 10.8 112 1210 70 9.7 106 652 91 11.5 135 344 125 10.2 105 261 158 14 109 269 151 16 137 940 109 13.1 117 947 96 13.4 130 1240 87 11.2 117 1400 1060 545

83 85 106

10.2 10.7 9.5

February 2009

AmmDis. TP OPDis. SSC SSQ E. coli pH (N mg/L) (mg/L) (mg/L) (cfu/100mL) (mg/L) (tons/day) 8.4 0.039 0.25 0.22 48 12 10 8.2 0.039 0.31 0.22 22 5 3.6 7.9 0.039 0.35 0.26 44 10 10 8.8 0.03 0.15 0.1 24 10 25 8.8 0.039 0.18 0.15 11 7 17 8.7 0.039 0.17 0.15 25 5 12 8.2 0.039 0.11 0.09 130 6 20 8.4 0.09 0.18 0.16 34 4 8.3 8.4 0.04 0.24 0.2 36 5 8.3 7.9 0.43 77 3 2.3 7 0.52 52 3 2.1 6.8 0.05 10 18 198 0.09 20 35 548 0.04 11 18 335 0.05 58 20 234 0.12 42 4 14 0.07 57 3 9.8 0.24 490 3 5.3 0.63 130 4 3.7 0.64 26 4 2.8 0.47 19 4 2.9 8.1 0.17 14 4 10 8.1 0.12 20 3 7.7 7.3 0.11 18 5 17 0.019 0.076 114 7.2 0.11 30 5 19 122 7.7 0.09 45 5 14 104 7 0.24 S 43 2 2.9

146

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Site ID Date 13206000 10/23/2007 13206000 11/20/2007 13206000 1/8/2008 13206000 3/18/2008

WT AT Time (*C) (*C) 12:00 12:20 8 11:20 2.1 10:20 6.2

February 2009

DO Q SpC DO (% AmmDis. TP OPDis. SSC SSQ E. coli (cfs) (uS/cm3) (mg/L) sat.) pH (N mg/L) (mg/L) (mg/L) (cfu/100mL) (mg/L) (tons/day) 271 242 270

148 143 135

11.5 12.7 11.9

106 102 105

7.1 7.1 7.2

0.44 0.39 0.04

120 43 23

Sewer outflow near Eagle 13206303 13206303

6/27/2007 17:30

13210007 13210007 13210007 13210007

2/15/2006 4/18/2006 5/16/2006 6/13/2006

0.212

6.12

Boise River at Star Bridge 13210007 10:15 1.7 13:30 7.1 12:20 10.6 12:20 11.7

4050 11 5830 6960 4450

105 87 76 68

13.1 13.8 11.8 10.9

103 6.8 123 116 111

0.07 0.12 0.04 0.07

11 23 56 88

15 35 14 18

164 551 263 216

Fivemile Creek 13210795 13210795

5/2/2005

9:00 10.8

14

31

199

13210795

6/6/2005

8:32 12.3 11.5

73

186

13210795

7/5/2005

8:50 15.8

19

603

241

13210795

8/8/2005

8:00 17.8 20.5

50

264

13210660 13210660 13210660 13210660

5/2/2005 10:15 9.9 14 6/6/2005 10:10 12.2 11.5 7/5/2005 10:40 15.1 19 8/8/2005 9:30 17.5 20.5

56 70 75 70

7.8

77 7.8

0.12

0.47

0.33

490

129

11

7.7

0.04

0.26

0.17

690

53

10

9

99 7.4

0.33

0.56

0.39

2900

71

116

6.1

70 7.3

0.04

0.39

0.28

360

72

9.7

0.07 0.02 0.06 0.02

0.22 0.16 0.33 0.35

0.15 0.1 0.15 0.17

280 490 680 990

65 66 164 162

9.9 13 33 31

Tenmile Creek 13210660 181 202 218 276

7.6 8.7 7.1

73 7.7 7.8 95 7.6 81 7.5

147

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Site ID

Date

February 2009

DO WT AT Q SpC DO (% AmmDis. TP OPDis. SSC SSQ E. coli Time (*C) (*C) (cfs) (uS/cm3) (mg/L) sat.) pH (N mg/L) (mg/L) (mg/L) (cfu/100mL) (mg/L) (tons/day)

Fifteenmile Creek 13210815 13210815 13210815 13210815 13210815

5/2/2005 6/6/2005 7/5/2005 8/8/2005

12:55 11:45 12:10 11:00

14.1 21 13.8 15 17.3 28.5 17.8 30

61 102 85 79

259 228 254 280

7.7 8.7 7.7

82 7.8 7.9 99 7.7 89 7.7

0.06 0.04 0.08 0.02

0.39 0.23 0.38 0.37

0.28 0.16 0.24 0.23

1900 650 1200 1200

69 54 72 97

11 15 17 21

0.4 0.14 0.14 0.12 0.12 0.12 0.16 0.33 0.47 0.37 0.16 0.16 0.16 0.12 0.15 0.22

7 33 200 99 54 60 34 20 7 71 83 260 80 72 78 36 16 23 100 56 43

9 13 4 10 5 5 8 5 5 29 11 7 5 6 5 4 4 6 8 8 5

8.8 22 4.3 13 7.8 9 7.8 3.9 4.1 43 11 5 3.9 9.2 5.1 3.9 3.1 4.5 12 15 4.2

Boise River above Middleton 13210050 13210050 2/19/2003 12:35 6 5.5 13210050 4/16/2003 11:30 10.3 11.5 13210050 5/14/2003 11:05 13.2 16 13210050 6/18/2003 10:50 16.3 26 13210050 7/16/2003 10:36 17.9 25.5 13210050 8/13/2003 10:40 18.9 23 13210050 9/17/2003 15:28 17.2 18 13210050 10/22/2003 14:32 15 20 13210050 12/17/2003 14:23 5.8 8 13210050 2/19/2004 11:00 5.4 6 13210050 4/13/2004 14:48 12.6 23 13210050 5/11/2004 16:00 13 16 13210050 6/16/2004 14:02 17.3 22 13210050 7/21/2004 14:27 19.9 31.5 13210050 8/25/2004 15:10 19.1 24 13210050 9/22/2004 15:36 16.9 17.5 13210050 11/8/2005 13:12 9.8 11 13210050 12/20/2005 11:20 2.6 13210050 7/11/2006 11:40 17.4 13210050 8/21/2006 10:40 17.1 13210050 9/13/2006 12:35 15.5

364 634 395 487 578 664 361 288 302 544 363 265 292 565 377 361 291 277 536 680 310

229 153 152 128 107 125 165 221 247 221 162 158 139 125 144 165 235 232 108 118 381

15.7 13.1 13.5 10.8 9.7 8.8 12 12.6 14.6 12.7 15.3 13.2 13.3 11.2 10.7 11.8 12.2 13.3 9.9 8.8 9.3

138 127 140 121 112 103 135 136 126 109 158 138 150 134 127 133 117 105 114 100 102

148

8.5 8.5 8.7 8.1 7.6 7.5 8.6 8.5 8.6 7.6 8.8 8.4 8.8 8 8.1 8.4 8.2 7.2

0.039 0.039 0.039 0.039 0.039 0.039 0.039 0.039 0.039 0.09 0.039 0.039 0.039 0.039 0.039 0.039

0.49 0.19 0.18 0.16 0.17 0.16 0.2 0.38 0.57 0.5 0.22 0.2 0.18 0.16 0.19 0.27 0.59 0.68 0.19 0.22 0.38

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Site ID Date Time 13210050 10/17/2006 11:00 13210050 12/19/2006 12:00 13210050 2/20/2007 11:30 13210050 4/10/2007 11:00 13210050 5/15/2007 10:50 13210050 6/19/2007 10:40 13210050 7/17/2007 10:15 13210050 8/7/2007 11:00 13210050 9/18/2007 11:30 13210050 11/20/2007 10:50 13210050 1/8/2008 12:50 13210050 3/18/2008 11:55

DO WT AT Q SpC DO (% (*C) (*C) (cfs) (uS/cm3) (mg/L) sat.) 10.8 348 204 9.9 98 0.8 325 240 14.1 106 7.8 350 253 12.7 117 8 560 151 11.1 102 13.4 280 161 11.4 119 15.3 886 127 9.2 100 18 700 119 8.3 97 18.3 450 132 9.1 106 15.6 291 165 9 99 8 296 220 10 91 2.6 295 247 13.4 108 8.2 342 235 12.2 112

February 2009

AmmDis. TP OPDis. SSC SSQ E. coli pH (N mg/L) (mg/L) (mg/L) (cfu/100mL) (mg/L) (tons/day) 0.62 27 0.71 33 0.69 41 7.7 0.29 66 8 12 7.6 0.22 130 9 6.8 6.8 0.21 100 14 33 6.8 0.18 100 9 17 6.9 0.21 50 7 8.5 7.5 0.35 S 41 3 2.4 7.1 0.51 20 7.8 0.58 12 8.1 0.06 150

Mill Slough 132108247 132108247 132108247 132108247 132108247

5/4/2005 6/8/2005 7/7/2005 8/10/2005

12:00 13.3 18 12:00 14 16.5 11:05 18.1 28 11:30 18.4 30.5

80 121 92 117

310 209 269 255

8 8.1 7.6

83 7.6 7.7 94 7.4 88 7.6

0.04 0.039 0.039 0.039

0.26 0.18 0.22 0.23

0.18 0.13 0.17 0.18

840 390 240 280

35 15 15 12

7.6 4.9 3.7 3.8

0.039 0.06 0.039 0.039

0.17 0.16 0.17 0.12

0.13 0.1 0.1 0.08

1000 770 920 500

16 22 24 12

0.91 1.7 1.9 0.78

0.47 0.03

0.69 0.32

0.45 0.21

1400 840

227 140

52 56

Willow Creek 13210835 13210835 13210835 13210835 13210835

5/4/2005 10:15 13.4 13.5 6/8/2005 10:00 17.5 7/7/2005 9:10 19.3 23.5 8/10/2005 9:25 20.2 26

21 29 30 24

148 139 149 122

7.2 7.2 8.3

75 7.8 7.6 85 7.5 101 7.6

Mason Creek 13210985 13210985 13210985

5/4/2005 6/8/2005

8:05 12.8 12.5 8:00 12 11.5

84 148

385 361

6.6

68 7.8 7.8

149

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Site ID 13210985 13210985

February 2009

DO WT AT Q SpC DO (% AmmDis. TP OPDis. SSC SSQ E. coli Date Time (*C) (*C) (cfs) (uS/cm3) (mg/L) sat.) pH (N mg/L) (mg/L) (mg/L) (cfu/100mL) (mg/L) (tons/day) 7/7/2005 7:15 17.3 19 127 401 7.3 83 7.6 0.21 0.65 0.32 770 330 113 8/10/2005 7:40 18.3 18 123 404 7.2 84 7.5 0.02 0.51 0.25 340 235 78

Indian Creek 13211445 13211445 13211445 13211445 13211445 13211445

5/3/2005 6/7/2005 7/6/2005 8/9/2005 6/27/2007

12:05 11:35 11:25 11:45 12:30

14.8 19.5 13.8 16 18.2 29 19.6 34 17.3 26

23 72 71 79

13212550 13212550 13212550 13212550

5/3/2005 10:10 13.7 17 6/7/2005 10:00 13.1 13.5 7/6/2005 9:50 17.2 27 8/9/2005 10:05 17.8 29.5

25 39 29 34

13212890 13212890 13212890 13212890

5/3/2005 6/7/2005 7/6/2005 8/9/2005

8:00 8:05 7:55 8:10

13213000 13213000 13213000 13213000 13213000

2/19/2003 4/16/2003 5/14/2003 6/18/2003 7/16/2003

16:10 14:45 14:42 14:10 14:09

404 411 376 7.6 350 8.2 363 8.9

8.1 8 7.8 7.9 8.2

88 98 102

0.09 0.02 0.06 0.03 0.016

0.63 0.45 0.5 0.51

0.55 0.39 0.39 0.41 0.467

630 310 520 550

51 52 70 68

3.1 10 13 15

0.039 0.039 0.04 0.03

0.26 0.25 0.95 0.69

0.1 0.09 0.11 0.12

230 480 690 610

125 165 739 496

8.5 17 58 46

0.05 0.0396 0.03 0.04

0.52 0.37 0.39 0.46

0.36 0.3 0.29 0.34

7700 1300 2900 620

108 55 58 50

50 33 30 27

0.44 0.31 0.25 0.29 0.31

0.35 0.17 0.19 0.23 0.23

31 280 290 24 9

22 63 36 28 30

47 155 93 59 58

Conway Gulch 13212550 577 461 514 551

7.8 7.9

8.2 8 89 8 91 8

Dixie Slough 13212890 13.5 13.5 13.6 11.5 18.9 21 19.7 24

171 223 190 199

7.5 13.4 17.3 21.7 23.3

795 910 961 778 722

431 423 420 412

7.1 6.2

7.7 7.8 83 7.3 74 7.4

Boise River near Parma 13213000 10.5 16 22.5 31.5 32.5

473 278 315 344 336

13.3 10.9 11.1 8.7 9.7

121 113 125 109 123

150

8.3 8.2 8.3 8.1 8.2

0.039 0.039 0.039 0.039 0.039

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Site ID 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000 13213000

Date 8/13/2003 9/17/2003 10/22/2003 12/17/2003 2/19/2004 4/13/2004 5/11/2004 6/16/2004 7/21/2004 8/25/2004 9/22/2004 10/19/2004 12/14/2004 2/15/2005 4/6/2005 5/2/2005 5/16/2005 5/31/2005 6/13/2005 7/18/2005 7/31/2005 8/15/2005 8/29/2005 9/12/2005 11/8/2005 12/20/2005 2/15/2006 4/19/2006

Time 14:12 11:00 11:07 11:00 14:23 11:20 11:28 10:28 10:44 11:05 11:14 11:54 11:10 12:08 11:40 13:00 13:30 12:42 11:43 12:30 10:48 11:37 9:30 13:30 10:16 9:00 12:45 11:30

WT (*C) 21.9 14.6 13.4 5.9 8.2 13.3 12.2 16.1 21.4 18 13.7 11.5 7.8 5.6 10.8 15.9 14.3 18.5 16.3 20.7 21.9 19 18.9 5.9 9.5 3.2 2.7 7.8

DO AT Q SpC DO (% (*C) (cfs) (uS/cm3) (mg/L) sat.) 29 772 342 10 123 13 910 395 9.5 101 11 885 501 9.9 103 3 812 518 11.9 103 10 1190 442 12.1 111 17 588 360 10 104 15 891 369 9.6 98 17 560 399 9.2 101 25 891 346 6.8 84 21 848 374 7.7 89 12.5 968 375 9.4 98 11.5 795 452 11.9 120 6.5 801 498 10.8 98 1 755 13.6 14.5 432 468 11.5 112 18 376 434 10.3 112 12 1360 297 8.3 90 22 555 371 9.3 107 20.5 579 390 9.8 108 29.5 628 351 8.7 106 28 505 383 7.6 94 23 330 8.7 102 23.5 830 335 7.5 89 17 801 376 11.6 100 7 848 489 10.6 100 744 482 12.5 100 4430 187 12.5 100 6610 126 10.6 96

151

February 2009

AmmDis. TP OPDis. SSC SSQ E. coli pH (N mg/L) (mg/L) (mg/L) (cfu/100mL) (mg/L) (tons/day) 8.2 0.039 0.3 0.21 16 33 69 8 0.039 0.28 0.22 140 22 54 8.1 0.039 0.31 0.27 50 20 48 8.2 0.039 0.5 0.41 79 14 31 8.1 0.07 0.48 0.29 93 85 273 7.8 0.09 0.38 0.26 980 61 97 7.9 0.04 0.41 0.26 1300 84 202 7.9 0.039 0.29 0.23 200 29 44 7.4 0.03 0.4 0.26 64 77 185 7.6 0.039 0.3 0.22 78 46 105 7.8 0.039 0.28 0.22 120 26 68 7.9 0.039 0.33 0.28 68 10 21 8 0.039 0.42 0.41 76 12 26 8.2 0.039 0.47 0.4 61 21 43 8.1 0.039 0.45 0.38 240 21 24 7.7 0.41 520 7.5 0.03 0.35 0.21 580 119 437 7.7 0.36 190 53 79 7.9 0.039 0.36 0.27 99 43 67 7.8 0.03 0.42 0.32 100 65 110 8 0.37 51 39 53 7.9 0.36 130 72 7.8 0.32 100 56 125 8.3 0.039 0.28 0.23 54 26 56 8.1 0.4 70 14 32 7.5 0.46 140 56 112 7.2 0.14 44 24 287 0.17 82 53 946

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Site ID Date Time 13213000 5/17/2006 11:00 13213000 6/14/2006 9:10 13213000 7/12/2006 7:45 13213000 8/21/2006 8:30 13213000 9/13/2006 9:30 13213000 10/17/2006 9:10 13213000 12/19/2006 10:00 13213000 2/20/2007 9:20 13213000 4/10/2007 9:00 13213000 5/15/2007 8:40 13213000 6/19/2007 8:15 13213000 7/17/2007 8:00 13213000 8/7/2007 8:45 13213000 9/18/2007 9:00 13213000 11/20/2007 8:45 13213000 1/9/2008 11:00 13213000 3/19/2008 9:10

DO WT AT Q SpC DO (% (*C) (*C) (cfs) (uS/cm3) (mg/L) sat.) 13.2 7080 119 12 124 13 4940 135 10.9 112 20.1 1020 308 7.8 94 17.8 1100 311 8.3 95 19 873 381 9.3 109 10.1 848 455 8.8 85 1.3 796 503 12.8 97 5.9 785 511 11.3 99 8.8 658 332 9.8 91 14.8 548 380 8.3 89 17.1 967 303 7.9 88 20.5 931 319 6.9 84 18.6 712 373 7.6 89 15.4 680 418 7.6 83 8.9 774 480 9.6 88 3.3 753 505 11.5 93 9.2 812 469 8.8 83

February 2009

AmmDis. TP OPDis. SSC SSQ E. coli pH (N mg/L) (mg/L) (mg/L) (cfu/100mL) (mg/L) (tons/day) 0.12 330 36 688 0.19 610 243 3240 0.34 300 80 220 0.27 230 46 137 0.31 130 22 52 0.44 150 13 30 0.47 100 14 30 0.49 99 19 40 8 0.41 770 57 101 7.7 0.36 1400 66 98 7.3 0.3 110 59 154 7.2 0.3 410 48 121 6.9 0.28 120 22 42 7.6 0.34 280 37 68 7.4 0.45 68 7.8 0.4 91 7.9 0.13 76

WT = Water Temperature; *C = degrees Celsius; AT = air Temperature; Q = discharge; cfs = cubic feet per second; SpC = Specific Conductance; uS/cm3 = microSiemens per cubic centimeter; DO = Dissolved Oxygen; mg/L = milligrams per liter; % sat = percent saturation; Amm Dis. = Dissolved Ammonia; TP = Total Phosphorus; OP Dis. = Dissolved Ortho-Phosphorus; cfu = colony-forming units; SSC = Suspended Sediment Concentration; SSQ = Suspended Sediment Discharge

152

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table C-2. Data provided by the Idaho State Department of Agriculture from locations in the Lower Boise River subbasin between 1998 and 2007. ISDA Water Quality Analysis Date 5/6/1998 5/27/1998 6/10/1998 6/24/1998 7/8/1998 7/23/1998 8/5/1998 9/2/1998 9/16/1998 9/30/1998 water off 10/15/1998 10/29/1998 11/18/1998 12/10/1998 1/14/1999 2/10/1999 3/9/1999 4/6/1999 4/24/2008 5/8/2008 5/22/2008 6/5/2008 6/19/2008 7/2/2008 7/17/2008 7/31/2008 8/14/2008

DO SpC TSS Nitrate/ TP FC E. coli DO WT (% (uS/ (mg/ Nitrite (mg/ OP Dis. (cfu/100 (cfu/100 (mg/L) (*C) sat.) cm3) TDS pH Q (cfs) L) TVS (mg/L) L) (mg/L) mL) mL) Sand Hollow 7.3 15.5 73.3 400 275 7.99 111 220 22 1.7 0.52 0.17 3200 1500 8.0 10.9 72.5 389 268 8.6 na 36 4 1.5 0.27 0.18 3600* 3500* 7.2 15.3 72 352 243 7.87 134.5 140 13 1.4 0.4 0.15 3600 3600 8.0 16.2 80.6 414 202 8.43 111.6 130 18 2.1 0.41 0.18 2600 <33 6.9 20.3 76.2 440 215 7.93 122.2 200 19 1.8 0.45 0.19 4000 470 6.7 20.9 75.3 453 221 8.13 116.3 380 26 2.2 0.56 0.22 4300 650 6.5 20.7 72.9 471 230 7.99 120.4 170 16 1.9 0.45 0.21 4300 3800 7.9 18.8 84.8 431 211 7.74 121.1 97 10 1.9 0.37 0.21 1800 1300 7.3 18.3 77.6 509 248 8.1 125.41 64 8 2.3 0.3 0.2 1300 400 8.1 15.1 80.1 479 234 8.18 128.5 54 6 2.2 0.27 0.17 400 250

9.7 10.2 10.4 13.1 11.4 11.8 10.8 9.5 10.2 8.6 9.4 8.6 8.0 7.3 7.4 7.9 7.4

10.9 9.2 8.2 3.1 5.3 2.8 5.8 7.6 8.9 11.5 10.5 12.5 16.5 19.7 19.1 17.8 19.0

87.8 88.5 88.0 97.9 89.7 87.5 86.3 79.2 88.9 79.3 84.1 81.6 81.8 80.1 80.4 82.8 80.0

556 680 674 704 450 787 731

270 335 327 343 365 385 424

477 525 406 438 494 489 427 442 470

234 257 199 215 242 240 209 217 231

8.24 8.24 8.44 8.3 8.26 8.31 8.38 8.02 8.35 8.12 7.64 8.12 7.61 8.02 7.84 8.12 8.22

93.5 65.2 63 53.9 44.1 51 41.8 51.2 106.3 98.3 166.3 187.7 114.2 115.1 204.2 152.5 150.2

47 29 35 54 57 92 40 89 113 76.3 127 66.5 103 112 180 117 118

4 4 5 7 7 10 6 10

2.7 3.9 3.6 4.9 4.4 4.9 4.1 3.3

153

0.28 0.31 0.33 0.39 0.35 0.33 0.22 0.3 0.481 0.421 0.456 0.346 0.438 0.538 0.49 0.42 0.437

0.19 0.23 0.26 0.26 0.23 0.22 0.12 0.14 0.268 0.224 0.2 0.174 0.221 0.273 0.219 0.196 0.236

350 400 1200 570 500 300 230 700

300 360 180 270 500 300 230 200 >2400 730 1000 730 580 1100 1000 1000 730

Lower Boise River 5-year Subbasin Assessment and TMDL Review

DO Date (mg/L) 8/28/2008 7.9 9/11/2008 8.9 9/25/2008 8.6

February 2009

DO SpC TSS Nitrate/ TP FC E. coli WT (% (uS/c (mg/ Nitrite (mg/ OP Dis. (cfu/100 (cfu/100 (*C) sat.) m3) TDS pH Q (cfs) L) TVS (mg/L) L) (mg/L) mL) mL) 16.2 80.8 449 220 7.98 168.8 62.1 0.368 0.219 870 14.1 86.1 514 252 8.02 162.7 34 0.271 0.183 250 14.1 83.3 540 265 7.93 176 30.9 0.241 0.186 190

4/4/2000 4/18/2000 5/3/2000 5/16/2000 5/31/2000 6/14/2000 6/27/2000 7/11/2000 7/25/2000 8/3/2000 8/22/2000 9/6/2000 9/19/2000 10/3/2000 10/18/2000 11/14/2000 12/14/2000 1/30/2001 2/21/2001 3/19/2001

10.3 8.2 8.3 7.8 10.4 10.2 8.5 8.7 7.1 6.0 6.8 7.5 6.9 8.1 8.7 11.2 10.7 11.8 9.8 11.3

8.6 268 136 8.29 11.8 76.1 373 186 7.81 13.2 79.4 395 198 7.52 14.1 76.1 345 174 7.96 12.8 98.1 555 276 7.94 16.7 104.5 393 197 7.73 18.0 89.5 434 217 7.64 19.3 94.5 390 197 7.41 19.7 77.9 395 199 7.34 20 65.2 401 201 7.76 17.0 69.9 402 201 7.83 15.0 74.1 405 201 7.86 17.7 72.8 431 223 7.83 13.2 77.3 447 216 7.94 12.5 81.8 555 268 7.98 6.9 91.8 755 366 8.27 6.5 86.7 752 376 8.38 3.3 88.2 792 386 8.36 6.9 80.6 673 333 8.14 11.4 103.6 731 367 8.41

4/24/2008 5/8/2008 5/22/2008 6/5/2008 6/19/2008 7/2/2008 7/17/2008

10.9 9.8 10.1 9.3 8.9 8.6 8.7

9.8 10.7 10.3 12.2 14.4 16.7 16.4

96.2 88.8 90.7 86.8 86.8 89.2 88.7

608 475 473 464 573 538 509

298 233 232 227 281 264 249

Dixie Slough 47 26 37 146 80 74 241 80 250 63 209 43 201 60 250 59 250 48 297 53 297 24 347 18 269 20 290 20 245 13 76 9 38 7 20 19 68 142 22 15

4 18 7 8 <2 6 7 4 6 9 <2 3 6 3 <2 2 <2 5 22 4

0.28 1.91 1.26 1.75 2.06 2.01 1.55 1.56 1.42 1.58 1.84 2.19 2.11 2.4 3.41 4.6 4.53 5.66 4.2 4.36

Conway Gulch 8.32 22.62 54 8.28 43.4 272 8.21 41.9 256 8.21 48.2 116 8.15 35.4 336 8.16 40.9 669 8.13 37.3 390 154

0.32 0.39 0.32 0.36 0.38 0.36 0.33 0.47 0.45 0.36 0.29 0.33 0.32 0.29 0.34 0.2 0.21 0.19 1.09 0.21

0.25 0.24 0.23 0.24 0.29 0.28 0.3 0.32 0.35 0.32 0.29 0.32 0.31 0.29 0.33 0.15 0.16 0.11 0.81 0.13

0.256 0.73 0.625 0.35 0.665 0.94 0.855

0.15 0.181 0.166 0.119 0.156 0.187 0.191

820 na 3400 1700 2500 630 870 1100 2200 730 1000 3200 1200 1600 100 66 130 210 240 1100

300 na 3300 1600 1200 530 530 400 2200 730 770 670 930 770 100 33 100 150 21 210

59 390 1200 240 340 310 240

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date 7/31/2008 8/14/2008 8/28/2008 9/11/2008 9/25/2008 10/9/2008 4/24/2008 5/8/2008

DO (mg/L) 8.6 8.5 9.0 9.1 8.8 9.7 10.9 9.8

DO SpC WT (% (uS/ (*C) sat.) cm3) TDS 15.5 87.0 533 261 16.4 86.2 558 273 14.7 88.2 544 267 13.5 87.5 526 258 14.1 85.4 500 245 11.1 88.3 566 277 9.8 96.2 608 298 10.7 88.8 475 233

pH Q (cfs) 8.22 46 8.27 41.4 8.19 41.5 7.87 53.6 7.87 56 7.98 40.6 8.32 22.62 8.28 43.4

TSS Nitrate/ TP FC E. coli (mg/ Nitrite (mg/ OP Dis. (cfu/100 (cfu/100 L) TVS (mg/L) L) (mg/L) mL) mL) 197 0.476 0.15 370 142 0.333 0.157 180 58 0.249 0.146 120 37 0.221 0.121 260 57 0.208 0.134 72 34 0.189 0.121 110 54 0.256 0.15 59 272 0.73 0.181 390

Indian Creek Location: I-1 4/27/1998 no sample - extreme depth and velocity 5/4/1998 no sample - extreme depth and velocity 5/18/1998 no sample - extreme depth and velocity 5/26/1998 8.6 12.6 81.0 485 334 8.02 na 48 5 6/9/1998 8.4 14.5 82.4 676 466 8.29 na 33 5 6/23/1998 8.3 15.2 82.3 638 311 7.42 171.1 27 4 7/7/1998 8.1 17.0 84.0 590 287 7.78 na 50 2 7/21/1998 8.0 17.8 83.9 591 288 7.75 na 76 9 8/4/1998 7.7 18.3 82.4 593 290 7.89 na 53 6 8/31/1998 8.9 17.2 92.8 557 272 7.89 na 40 6 9/15/1998 8.1 16.9 83.8 534 260 8.33 na 42 5 9/28/1998 8.4 15.6 84.2 588 286 8.18 na 31 <4 10/7/1998 327.5 water off 10/14/1998 10/28/1998 11/17/1998 12/8/1997 1/12/1999 2/9/1999 3/8/1999 4/5/1999

9.0 9.0 na 10 9.6 na 9.5

13.5 13.7 na 10.2 10.4 9.2 9.7 10.1

86.3 86.9 na 88.8 85.6 na 83.6

688 733 734 741 733 698 778 609

337 357 358 362 355 344 445 350

8.13 8.1 na 8.48 8.02 na 8.1 8.25 na 8.24 217.4 7.97 224

February 2009

27 29 35 21 58 89 60 86

8 4 4 4 7 10 7 11

3.9 6.4 5.9 5.2 4.7 4.8 4.1 4.3 4.1

0.44 1.3 0.89 0.54 0.66 0.69 0.67 0.54 0.54

0.35 0.65 0.86 0.45 0.58 0.64 0.61 0.52 0.47

1600* 900 470 1900 1600 2700 800 2100 600

1000* 830 400 500 750 2300 700 700 200

5 5.6 6 13 6.6 7.4 7.3 5.2

0.61 0.45 0.62 1.9 0.63 0.7 0.54 0.59

0.56 0.39 0.57 1.6 0.52 0.52 0.41 0.47

300 480 420 430 470 550 230 230

100 140 280 170 130 550 230 130

155

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

DO SpC TSS Nitrate/ TP FC E. coli DO WT (% (uS/c (mg/ Nitrite (mg/ OP Dis. (cfu/100 (cfu/100 mL) mL) Date (mg/L) (*C) sat.) m3) TDS pH Q (cfs) L) TVS (mg/L) L) (mg/L) East Hartley Drain 4/5/2001 10.9 10.5 97.7 609 312 8.34 14.6 8 0.29 0.25 23 23 4/17/2001 9.5 13.2 91.0 479 246 8.17 18.9 61 0.28 0.21 460 1100 5/1/2001 9.8 12.3 91.3 318 159 8.16 51.5 150 0.38 0.24 >2400 1100 5/15/2001 8.8 13.4 83.9 302 153 7.84 83.3 140 0.47 0.28 11000 11000 5/30/2001 8.8 14.0 85.3 268 137 7.99 78.3 76 0.27 0.19 >24000 >24000 6/12/2001 8.2 14.2 80.0 307 153 7.99 73.2 52 0.28 0.2 1500 1500 6/27/2001 6.3 18.3 66.9 342 175 7.77 63 75 0.34 0.3 2400 2400 7/10/2001 19.3 345 181 7.86 67.1 123 0.35 0.25 4600 750 7/31/2001 16.3 348 174 7.92 71.2 52 0.3 0.24 500 500 8/9/2001 7.2 18.0 75.5 403 202 7.93 69.1 43 0.38 0.32 >25000 >25000 8/20/2001 8.1 16.5 83.4 370 186 8.05 73.5 36 0.28 0.26 700 2900 9/6/2001 8.9 15.0 88.6 381 191 na 80.7 19 0.33 0.28 1100 2800 9/24/2001 8.6 14.8 84.8 482 245 8.05 45.2 70 0.31 0.26 200 6200 10/2/2001 9.2 14.2 89.6 502 255 7.98 42.3 7 0.27 0.27 250 250 10/16/2001 10.2 12.5 93.6 500 248 8.29 37.1 15 0.24 0.24 100 100 11/13/2001 11.0 12.4 98.1 591 295 8.08 17.3 8 0.26 0.26 330 330 12/11/2001 no samples collected 1/29/2002 11.1 6.0 89.5 618 318 8.01 17.5 66 0.21 0.21 130 230 2/26/2002 13.3 5.2 104.3 637 311 8.1 15.1 46 0.24 0.21 170 70 3/20/2002 13.9 10.5 125.2 597 299 8.4 14.6 17 0.23 0.23 100 180 11/1/2006 10.1 10.5 90.15 570 280 7.9 14.6 0.32 0.24 1/25/2007 10.1 9.5 87.95 596 288 8.2 9.5 0.28 0.25 11/29/2007 8.6 10.9 77.7 640 8.0 10.3 0.32 0.27

4/5/2001 4/17/2001 5/1/2001 5/15/2001 5/30/2001 6/12/2001 6/27/2001

10.2 9.1 9.3 8.1 7.7 8.0 6.0

9.0 12.2 11.4 13.9 15.1 15.0 19.4

88.3 84.6 85.3 78.9 76.1 79.1 65.2

499 253 294 145 212 108 176 88 146 73 167 82 184 92

West Hartley Drain 8.04 3.1 9 7.87 6.7 15 7.9 25.3 67 7.74 45.3 95 7.77 43 48 7.71 31.3 36 7.71 24.3 30

0.4 0.28 0.24 0.19 0.17 0.2 0.17

156

0.32 0.24 0.18 0.14 0.12 0.13 0.16

23 1100 460 930 11000 150 2400

23 >2400 460 930 11000 90 2400

Lower Boise River 5-year Subbasin Assessment and TMDL Review

DO DO WT (% Date (mg/L) (*C) sat.) 7/10/2001 20.3 7/31/2001 17.3 8/9/2001 7.2 19.5 78.5 8/20/2001 8.2 17.6 86.2 9/6/2001 8.5 16.4 87.2 9/24/2001 8.5 14.9 84.4 10/2/2001 9.0 13.9 87.3 10/16/2001 9.4 12.9 89.0 11/13/2001 9.6 12.5 90.6 12/11/2001 no samples collected 1/29/2002 11.6 6.3 94.1 2/26/2002 13.1 5.8 105.1 3/20/2002 11.7 10.4 104.9 11/1/2006 7.4 9.1 64.3 1/25/2007 10.1 7.0 84.3 11/29/2007 7.8 9.7 68.7

10/14/1998

TSS Nitrate/ TP FC E. coli (mg/ Nitrite (mg/ OP Dis. (cfu/100 (cfu/100 mL) mL) Q (cfs) L) TVS (mg/L) L) (mg/L) 25 38 0.2 0.17 1500 1500 42.1 23 0.23 0.19 <100 700 26.1 22 0.21 0.18 1600 1600 33.1 25 0.23 0.17 1400 1400 35.6 11 0.15 0.12 700 400 9.0 8 0.3 0.3 1700 100 7.4 4 0.33 0.33 200 200 5.9 6 0.37 0.36 500 900 6.0 2 0.37 0.37 170 170 3.8 3.1 2.8 5.7 3.4 4.0

14 7 14

0.4 0.32 0.35 0.75 0.55 0.64

0.34 0.32 0.35 0.47 0.37 0.51

280 80 140

340 70 240

0.27 0.36 0.47 0.45 0.44 0.43 0.35 0.28

0.13 0.2 0.29 0.25 0.3 0.28 0.28 0.22

1900* 1600 3100 2500 4700 25000 6700 1300

1400* 870 2500 600 1400 2700 6700 200

0.28

0.21

300

200

5.00 0.22

0.19

600

200

8.5 15.4 85.6

Mason Creek-mouth Location M-1 540 270 540 270 312 216 na 85 8 2.1 365 250 8.5 st.2.8' 130 12 3 363 175 8.05 na 160 12 3.1 379 186 7.92 na 150 10 3.2 409 199 7.95 na 140 12 3.7 414 201 7.82 na 120 11 3.4 392 191 8.01 na 61 6 2.8 400 195 7.98 na 47 5 2.8 too 397 193 7.91 deep 33 5 2.3

9.5 12.3 88.4

too deep

4/27/1998 no samples collected 5/4/1998 no samples collected 5/26/1998 9.3 10.8 83.9 6/9/1998 8.9 13.8 85.9 6/23/1998 8.9 15.4 89.5 7/7/1998 8.1 17.4 84.8 7/21/1998 7.5 18.4 80.2 8/4/1998 7.4 18.4 79.4 8/31/1998 8.7 18.8 93.5 9/15/1998 7.9 16.8 81.1 9/28/1998 water off

SpC (uS/ cm3) TDS pH 199 102 7.73 204 103 7.73 223 113 7.76 222 113 7.93 185 92 na 384 193 7.98 412 211 7.97 428 213 8.16 507 254 8 540 270 588 280 8.09 564 269 8.05 493 250 8.13 406 196 7.40 405 192 7.90 434 7.42

673 328 8.21

February 2009

25

7

157

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date 10/28/1998 11/17/1998 12/8/1998 1/12/1999 2/9/1999 3/8/1999 4/5/1999 4/24/2008 5/8/2008 5/22/2008 6/5/2008 6/19/2008 7/2/2008 7/17/2008 7/31/2008 8/14/2008 8/28/2008 9/11/2008 9/25/2008 10/9/2008

4/4/2000 4/18/2000 5/3/2000 5/16/2000 5/31/2000 6/14/2000 6/27/2000 7/11/2000 7/25/2000 8/3/2000

DO SpC (% (uS/c sat.) m3) TDS pH Q (cfs) too 12.4 93.6 671 327 8.2 deep 11.7 91.3 664 324 8.23 74.5 8.0 96.6 664 324 8.43 69.5 7.9 90.5 663 323 8.45 65.5 8.2 86.8 640 312 8.32 74.5 7.5 96.9 700 398 8.57 62.3 8.9 100.3 686 389 8.31 52.5 9.2 93.7 362 178 8.31 138.4 11.0 89.2 462 226 8.14 108 9.6 89.7 385 189 8.2 295 12.3 88.1 422 207 8.18 282 15.0 88.8 505 248 8.18 141.4 17.1 84.8 381 187 8.36 151.6 17.0 84.8 373 183 8.09 154.6 16.6 87.8 389 190 8.24 146.2 17.4 84.6 406 199 8.08 139.6 15.5 84.8 399 196 8.23 155 14.1 90.3 412 202 7.9 136.2 14.7 85.5 412 202 7.91 141.6 11.0 92.6 522 256 7.88 114.7

DO WT (mg/L) (*C) 10.0 9.9 11.5 10.8 10.2 11.6 11.6 10.8 9.8 10.2 9.4 9.0 8.2 8.2 8.6 8.1 8.5 9.3 8.7 10.2

11.0 8.8 8.7 8.6 10.7 10.4 10.1 10.7 9.4 8.3

14.6 12.5 14.0 13.1 12.8 16.1 16.7 18.3 18.4 18.9

108.9 82.7 84.3 81.9 101.3 106.0 103.8 114.4 99.8 89.0

293 150 132 65.3 107 53 102 52 243 112 157 79 160 80 157 79 180 91 174 88

February 2009

TSS Nitrate/ TP FC E. coli (mg/ Nitrite (mg/ OP Dis. (cfu/100 (cfu/100 L) TVS (mg/L) L) (mg/L) mL) mL) 12 9 24 35 120 77 27 136 71.2 88.9 71.5 136 106 71.6 87.4 51.6 39.2 32.3 26.1 21.5

Willow Creek 8.91 0 1 7.65 36.5 49 7.88 38.7 25 7.79 54.5 27 7.78 40.8 14 7.44 48.6 27 7.65 11.5 7 7.26 17.2 10 7.76 4.0 2 7.62 27.6 15

<4 <4 <4 5 14 10 <4

5.3 4.9 5.5 4.6 5.1 5.6 4.7

0.24 0.2 0.2 0.24 0.38 0.26 0.23 0.412 0.61 0.407 0.363 0.442 0.415 0.325 0.344 0.324 0.292 0.248 0.216 0.262

0.18 0.15 0.19 0.17 0.18 0.14 0.16 0.241 0.313 0.239 0.22 0.269 0.278 0.22 0.212 0.237 0.23 0.192 0.193 0.206

280 220 130 400 2700 170 130

280 200 130 270 330 170 50 140 690 730 820 730 520 690 310 240 170 410 180 170

<2 8 3 4 <2 4 2 2 <2 3

0.14 0.05 0.08 0.07 0.07 0.11 0.19 0.21 0.21 0.16

0.01 0.44 0.28 0.36 0.41 0.01 0.7 0.5 0.67 0.53

0.17 0.14 0.17 0.22 0.12 0.17 0.22 0.22 0.21 0.21

10 300 780 560 480 770 570 1700 1900 3300

10 240 780 560 300 430 570 1700 1300 3300

158

Lower Boise River 5-year Subbasin Assessment and TMDL Review

DO SpC DO WT (% (uS/c Date (mg/L) (*C) sat.) m3) TDS pH Q (cfs) 8/22/2000 8.9 16.1 90.5 181 91 7.67 4.0 9/6/2000 9.2 14.1 89.7 102 51 8 38.5 9/19/2000 8.3 18.1 87.6 128 64 7.8 15.1 10/3/2000 9.8 11.0 88.3 156 78.3 7.64 4.9 10/18/2000 9.4 11.3 85.9 314 154 7.99 4.8 11/14/2000 11.9 4.1 91.0 419 207 8.22 1.1 12/14/2000 12.4 3.2 92.8 436 217 8.4 0.9 1/30/2001 Just a trickle, too shallow, no data 2/21/2001 12.6 1.7 89.9 199 96 8.01 7.8 3/19/2001 9.6 10.1 84.9 374 191 8.06 0.7 4/24/2008 10.7 10.0 95.2 132 65 8.07 44.2 5/8/2008 10.3 12.1 95.2 158 77 8.07 35.7 5/22/2008 10.2 11.1 92.4 128 63 8.23 73.6 6/5/2008 9.6 13.7 92.3 129 63 8 83.5 6/19/2008 8.9 17.4 93.4 148 73 8.11 36.2 7/2/2008 8.0 20.4 88.3 211 103 7.8 12.9 7/17/2008 8.5 19.8 92.8 130 64 7.8 27.2 7/31/2008 8.6 19.0 93.2 136 67 8.15 42.5 8/14/2008 7.9 20.0 87.4 139 68 8.04 44.6 8/28/2008 9.3 16.9 96.2 128 62 8.05 27.1 9/11/2008 9.4 15.7 95.0 136 67 7.8 40.0 9/25/2008 9.4 15.1 92.9 112 55 7.82 39.2 10/9/2008 10.6 10.9 96.0 132 65 7.93 36.8

4/17/2008 5/1/2008 5/15/2008 5/29/2008 6/12/2008 6/26/2008 7/10/2008

12.0 11.9 8.7 8.3 7.7 7.2 9.3

5.4 5.9 12.3 12.8 12.3 16.2 15.6

95.6 95.2 81.8 78.2 72.1

176 291 497 486 601 701 93.5 742

86 143 243 238 295 343 364

7.95 7.73 7.5 7.54 7.48 7.66 7.74

February 2009

TSS Nitrate/ TP FC E. coli (mg/ Nitrite (mg/ OP Dis. (cfu/100 (cfu/100 L) TVS (mg/L) L) (mg/L) mL) mL) 1 3 0.19 0.66 0.19 >8300 800 7 2 0.07 0.22 0.1 370 330 6 3 0.1 0.42 0.11 2000 1900 6 3 0.12 0.54 0.12 670 230 2 <2 0.22 2.08 0.23 230 130 4 <2 0.21 2.29 0.23 100 100 8 <2 0.25 2.68 0.31 33 <33 196 4 30.4 25 70.3 22.2 21.3 14.4 27.1 27.4 15 15.3 13.9 30.9 10.6

36 2

Dry Creek 24.5 27.8 22.1 31.5 9.9 210 4.1 19.7 3.6 3.5 1.5 1.8 0.6 1.5

159

0.26 0.81 0.23 1.87 0.161 0.151 0.241 0.142 0.146 0.248 0.144 0.145 0.147 0.136 0.115 0.086 0.08

0.69 0.31 0.075 0.089 0.083 0.074 0.104 0.204 0.091 0.098 0.109 0.096 0.07 0.046 0.042

0.179 0.133 0.499 0.162 0.122 0.119 0.12

0.071 0.055 0.088 0.099 0.098 0.109 0.12

240 93

240 93 57 170 1300 370 650 1100 290 770 180 330 160 86 79

96 93 260 66 130 150 68

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date 4/23/2003 5/7/2003 5/21/2003 6/3/2003 6/18/2003 7/1/2003 7/15/2003 7/30/2003 8/26/2003

February 2009

DO SpC TSS Nitrate/ TP FC E. coli DO WT (% (uS/ (mg/ Nitrite (mg/ OP Dis. (cfu/100 (cfu/100 mL) mL) (mg/L) (*C) sat.) cm3) TDS pH Q (cfs) L) TVS (mg/L) L) (mg/L) Mill Slough near mouth-Location MS-1 8.5 11.6 82.3 259 141 7.65 12.4 22 0.23 0.19 10.6 12.3 99.1 210 113 7.62 46.8 29 0.17 0.13 10.5 13.0 100.0 237 122 7.43 24 15 0.18 0.17 9.2 14.1 84.4 233 119 7.22 29 15 0.19 0.17 7.7 16.6 79.4 271 141 7.31 15.7 12 0.28 0.28 7.9 17.5 82.3 271 140 7.1 18 3 0.26 0.26 7.6 17.5 79.8 261 136 na 17.7 9 0.23 0.21 6.4 18.8 69.3 253 132 na 21.2 8 0.24 0.26 6.1 18.0 64.3 243 128 29.2 7 0.18 0.18

4/29/1998 5/6/1998 5/27/1998 6/10/1998 6/24/1998 7/8/1998 7/23/1998 8/5/1998 9/2/1998

8.3 8.4 8.9 8.4 8.4 7.6 7.4 7.4 8.8

11.0 12.9 10.5 13.4 14.6 17.4 18.2 18.3 19.6

75.5 79.8 88.0 80.4 82.8 79.9 78.9 79.3 95.9

256 250 196 213 251 282 270 301 251

9/16/1998

7.6

17.7

79.6 288

9/29/1998 4/24/2008 5/8/2008 5/22/2008 6/5/2008 6/19/2008 7/2/2008 7/17/2008 7/31/2008 8/14/2008

8.8 11.4 12.1 10.9 10.0 9.6 8.8 9.1 9.7 9.4

15.2 87.6 278 8.1 96.3 189 10.5 108.5 269 9.6 95.8 191 11.7 91.8 198 15.0 94.9 273 16.7 90.9 284 16.4 92.5 252 17.0 100.9 261 17.6 98.5 278

Fifteenmile Creek 176 na 142.4 83 6 173 7.66 153.1 100 10 134 7.64 na 32 4 147 8.03 na 61 10 122 8.48 na 110 12 137 8.18 na 130 13 132 8.02 na 140 12 146 7.67 na 110 11 122 8.02 na 51 5 too 141 7.95 deep 30 5 too 135 8.06 deep 29 5 93 8.24 187.4 70.4 132 8.35 70.1 56.5 94 8.25 191.1 66 97 8 309.8 37.1 134 8.17 112.7 76.4 139 7.92 98.7 91.4 123 8.05 85.8 85 128 8.29 93.7 80.7 136 8.15 98.3 40.8

1.4 1.5 1.1 1.6 2.1 2.2 2.2 2.4 1.7

0.43 0.48 0.3 0.28 0.4 0.41 0.39 0.39 0.28

0.33 0.3 0.2 0.18 0.24 0.26 0.26 0.26 0.22

2200 1700 6600* 1200 1800 2300 11000 14000 4700

67 6400* 870 500 400 1100 2600 <100

2

0.24

0.19

600

600

0.24 0.349 0.379 0.312 0.308 0.326 0.378 0.33 0.312 0.341

0.17 0.228 0.279 0.18 0.187 0.231 0.229 0.213 0.218 0.263

150

100 39 170 980 980 1400 1400 580 290 490

1.6

160

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

DO SpC TSS Nitrate/ TP FC E. coli DO WT (% (uS/ (mg/ Nitrite (mg/ OP Dis. (cfu/100 (cfu/100 mL) mL) Date (mg/L) (*C) sat.) cm3) TDS pH Q (cfs) L) TVS (mg/L) L) (mg/L) 8/28/2008 9.7 15.3 97.0 282 138 8.23 104.2 29.7 0.357 0.286 370 9/11/2008 10.4 14.2 101.7 261 128 7.96 108.6 18.2 0.276 0.224 240 9/25/2008 9.2 14.7 91.0 255 125 7.93 111.8 27.8 0.277 0.219 180 water off 10/15/1998 10.5 10.9 94.6 527 258 8.2 49.6 4 <4 3.7 0.19 0.18 300 150 10/29/1998 12.4 9.7 109.6 630 308 8.32 31.3 2 <4 4.7 0.33 0.27 300 140 11/18/1998 11.8 8.1 99.7 612 299 8.5 28.3 2 <4 4.1 0.25 0.21 800 260 12/10/1998 13.9 2.7 102.5 616 300 7.99 23.6 10 <4 4.7 0.15 0.15 270 230 1/14/1999 11.5 4.8 89.6 614 299 8.24 22.6 17 4 3.9 0.26 0.21 570 430 2/10/1999 12.2 2.7 89.5 603 295 8.2 27.6 33 7 4.8 0.3 0.22 530 530 3/9/1999 no samples collected, location backed-up by Boise River 4/6/1999 no samples collected, location backed-up by Boise River

4/29/1998 5/6/1998 5/27/1998 6/10/1998 6/24/1998 7/8/1998 7/23/1998 8/5/1998 9/2/1998 9/16/1998 9/29/1998 water off 10/15/1998 10/29/1998 11/18/1998 12/10/1998 1/14/1999 2/10/1999

9.2 9.1 9.7 9.3 8.8 8.3 7.7 7.6 9.1 7.9 9.2

10.5 13.6 10.9 13.7 14.7 17.7 18.4 18.1 20.5 17.4 15.2

82.0 87.6 86.8 90.6 87.0 87.3 82.6 80.6 100.7 82.0 91.5

215 222 161 181 243 310 250 291 252 297 303

148 153 110 125 117 154 122 142 123 146 148

11.1 11.2 14.1 10.2 13.6 8.6 16.9 3.5 11.4 5.2 12.3 3.8

101.7 125.2 116.6 127.1 89.9 93.6

493 564 565 574 596 392

240 276 275 280 290 289

Tenmile Creek na 51.4 55 7.99 66.8 92 8.12 na 34 8.41 67.4 49 8.59 71.1 65 8.32 63.5 86 7.79 69.8 130 7.68 60.5 73 7.32 56.4 28 7.9 57.4 22 8.01 51.1 17

8.08 8.47 8.27 8.43

18.2 10.9 9.01 6.52 4.98 8.33 6.03

2 2 2 2 2 4

<4 13 5 <4 11 10 13 7 5 4 5

1.2 1.3 0.86 1.3 1.9 2.4 2.1 2.3 2 2.2 2.1

0.25 0.38 0.18 0.17 0.27 0.31 0.31 0.28 0.22 0.23 0.21

0.14 0.25 0.1 0.099 0.18 0.2 0.2 0.18 0.18 0.18 0.18

900 1000 2200* 330 2500 1900 1700 2600 3200 1100 300

600 2000* 300 570 370 1000 2000 100 600 250

<4 <4 <4 <4 <4 <4

4.3 4.8 4.6 6.2 5 6.1

0.18 0.25 0.23 0.24 0.25 0.25

0.18 0.21 0.19 0.2 0.24 0.24

100 60 <20 67 1300 100

50 20 <20 33 1300 67

161

Lower Boise River 5-year Subbasin Assessment and TMDL Review

DO (mg/L WT ) (*C) Date 3/9/1999 11.7 5.2 4/6/1999 10.4 6.2

4/29/1998 5/6/1998 5/27/1998 6/10/1998 6/24/1998 7/8/1998 7/23/1998 8/5/1998

8.9 9.0 9.3 9.0 8.4 7.6 7.3 7.2

10.6 13.9 11.2 14.6 15.5 17.4 19.1 18.7

9/2/1998

7.7

20.8

9/16/1998 9/29/1998

7.4 7.7

17.9 15.8

water off 10/15/1998 10/29/1998 11/18/1998 12/10/1998 1/14/1999 2/10/1999 3/9/1999 4/6/1999

11.3 13.7 13.0 13.9 11.9 12.4 11.8 10.5

11.2 9.8 8.2 3.0 5.3 3.3 6.2 7.3

DO (% sat.) 91.6 84.5

SpC TSS Nitrate/ TP FC E. coli (uS/ Q (mg/L Nitrite (mg/ OP Dis. (cfu/100 (cfu/100 cm3) TDS pH (cfs) ) mL) mL) TVS (mg/L) L) (mg/L) 382 216 8.62 13.3 11 <4 3.4 0.14 0.11 67 67 8.12 72.7 82 12 0.62 0.15 0.044 200 200

Fivemile Creek 137 na 57.8 88 132 7.74 57.3 80 141 8.52 na 40 151 8.16 74.1 45 120 7.45 82.4 170 128 7.65 97.3 110 129 7.93 84 180 145 7.65 101.4 97 too 86.5 240 117 7.72 deep 37 too 77.8 269 131 8.57 deep 30 78.3 273 133 7.88 >4.0' 31

80.3 87.3 84.6 89.2 84.4 79.9 78.5 77.2

102.6 121.3 110.7 103.2 94.0 93.0 86.0 87.5

February 2009

200 193 205 220 247 263 265 298

553 613 594 594 600 na 606

269 8.3 299 8.5 290 8.46 290 8.36 292 8.32 na 8.38 344 8.42 8.23

41.2 26 18.8 14.7 13.4 17.7 16.4 30

13 2 2 41 45 61 29 110

9 10 7 7 19 9 15 10

1.1 1.1 1.3 1.7 2 2.1 2.3 2.7

0.47 0.42 0.31 0.28 0.48 0.41 0.48 0.45

0.32 0.28 0.19 0.21 0.27 0.26 0.3 0.3

310 570 5400* 900 1800 2900 8200 8800

300 4800* 700 130 670 1500 8200

6

1.5

0.29

0.22

300

100

5 7

1.6 1.6

0.22 0.26

0.13 0.2

1800 400

300 250

<4 <4 <4 8 7 9 5 16

3.8 4 3.6 4.2 3.4 4.5 4.4 2

0.2 0.26 0.23 0.28 0.28 0.32 0.26 0.32

0.18 0.22 0.19 0.19 0.19 0.2 0.19 0.11

50 100 200 100 500 930 170 500

<50 20 100 67 500 800 170 500

DO = Dissolved Oxygen; mg/L = milligrams per liter; WT = Water Temperature; *C = degrees Celsius; % sat = percent saturation; SpC Specific Conductance; uS/cm3 = microSiemens per cubic centimeter; TDS = Total Dissolved Solids; Q = discharge; cfs = cubic feet per second; TSS = Total Suspended Sediment; TVS = Total Volatile Sediments; TP = Total Phosphorus; OP Dis. = Dissolved Ortho-Phosphorus; FC = Fecal Coliform; cfu = colony-forming units; mlfx = malfunction; * = estimated value

162

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table C-3. Data collected by City of Nampa near Indian Creek Wastewater Treatment Plant between 2003 and 2008. City of Nampa Indian Creek Wastewater Treatment Plant (WWTP)

E. coli (cfu/100 mL)

Date 3/28/2006 4/4/2006 5/7/2008 5/13/2008

Down Upstream stream WWTP WWTP 39.9 34.1 127.4 313 290.9

Indian Creek Water Quality Analysis Results Upstream and Downstream of WWTP 2003-2007 Upstream

Date 1/6/2003 1/14/2003 1/21/2003 1/28/2003 2/4/2003 2/11/2003 2/18/2003 2/25/2003 3/4/2003 3/11/2008 3/18/2003 3/25/2003 4/1/2003 4/8/2003 4/15/2003 4/22/2003 4/29/2003 5/6/2003

Downstream

FC Amm Q TSS DO WT (cfu/100 Dis. N TP (cfs) (mg/L) pH (mg/L) (*C) mL) (mg/L) (mg/L) 19.0 20 8.0 220 0.38 0.70 18.0 14 8.0 40 0.15 17.0 18 8.0 160 0.09 26.0 22 8.2 10.0 13 120 0.10 19.0 25 8.1 120 0.06 0.96 24.0 30 8.0 200 0.07 23.0 28 8.0 10.9 12.5 80 0.04 22.0 29 8.0 220 0.05 22.5 19 8.0 11.2 12.5 140 0.05 0.92 17.0 21 8.0 20 0.05 14.0 23 8.1 300 0.05 23.0 24 8.0 14.8 12.5 180 0.06 18.0 8 7.9 12.6 14.5 580 0.05 0.80 77.0 26 7.9 13.2 11.5 <33 0.05 67.0 22 7.9 14.4 11.5 100 0.07 70.0 24 7.9 11.5 12.5 240 0.06 43.0 13 8.0 13.0 13 120 0.05 70.0 15 7.8 10.4 13 80 0.05 0.46

163

Date 1/6/2003 1/14/2003 1/21/2003 1/28/2003 2/4/2003 2/11/2003 2/18/2003 2/25/2003 3/4/2003 3/11/2008 3/18/2003 3/25/2003 4/1/2003 4/8/2003 4/15/2003 4/22/2003 4/29/2003 5/6/2003

TSS (mg/L) 19 14 17 24 20 17 16 27 37 16 25 19 10 24 20 19 13 14

FC Amm DO WT (cfu/100 Dis. N TP pH (mg/L) (*C) mL) (mg/L) (mg/L) 7.7 100 0.28 2.05 7.3 20 0.18 7.7 160 0.09 7.8 9.4 14 140 0.14 7.5 100 0.06 3.25 7.6 160 0.06 7.7 10.0 13.5 40 0.05 7.5 120 0.06 7.7 10.2 14 60 0.06 3.00 7.6 40 0.05 7.7 180 0.05 7.8 12.8 14 120 0.06 7.6 12.8 16 120 0.06 3.35 7.6 13.0 12 167 0.06 7.8 13.2 13 160 0.07 7.6 11.1 14 240 0.07 7.6 12.0 15 140 0.06 7.5 10.3 14 120 0.05 1.75

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Q TSS DO Date (cfs) (mg/L) pH (mg/L) 5/13/2003 68.0 15 7.9 5/20/2003 22.5 11 7.9 5/27/2003 38.5 10 7.7 6/3/2003 49.5 27 7.9 9.4 6/10/2003 23.0 12 7.7 8.1 6/17/2003 22.5 6 7.8 9.0 6/24/2003 30.3 10 7.8 9.6 7/1/2003 24.0 9 7.8 9.4 7/8/2003 30.3 5 7.8 7/15/2003 27.0 3 7.8 10.0 7/22/2003 62.0 2 7.7 7/29/2003 67.0 3 7.4 8/5/2003 78.0 2 7.7 8/12/2003 77.0 1 7.6 8/19/2003 103.0 1 7.8 8/26/2003 100.0 3 7.7 7.7 9/2/2003 92.0 3 7.7 9/9/2003 95.0 3 7.8 8.4 9/16/2003 78.0 2 7.7 8.8 9/23/2003 99.0 5 7.8 9.5 9/30/2003 78.0 14 7.8 9.2 10/7/2003 75.0 2 7.8 10/14/2003 66.0 2 7.9 10/20/2003 44.0 5 7.9 10/28/2003 47.5 <1.0 7.9 9.3 11/4/2003 3.0 14 7.9 9.3 11/12/2003 41.0 2 7.9 11/18/2003 38.5 2 8.0 11/25/2003 11.5 2 8.0 12/2/2003 29.5 2 7.8 12/9/2003 22.5 3 8.0 12/16/2003 26.0 9 8.0 9.8

WT (*C)

17.5 21 20.5 18 20.5 21

24.5 16 17 17 17

16 12

11

FC Amm (cfu/100 Dis. N TP mL) (mg/L) (mg/L) 560 0.13 1020 1.44 860 0.07 680 0.06 0.62 900 1.03 660 0.06 1460 1.93 1240 3.26 660 0.17 0.96 780 0.05 440 0.05 860 0.06 940 0.05 0.702 500 0.04 280 0.07 620 0.07 440 0.04 220 0.05 0.62 360 0.05 480 0.05 1020 0.07 767 0.04 0.70 240 0.08 400 0.06 220 0.05 280 0.06 0.78 60 0.05 60 0.07 160 0.09 160 0.11 0.86 100 0.10 220 0.09

164

Date 5/13/2003 5/20/2003 5/27/2003 6/3/2003 6/10/2003 6/17/2003 6/24/2003 7/1/2003 7/8/2003 7/15/2003 7/22/2003 7/29/2003 8/5/2003 8/12/2003 8/19/2003 8/26/2003 9/2/2003 9/9/2003 9/16/2003 9/23/2003 9/30/2003 10/7/2003 10/14/2003 10/20/2003 10/28/2003 11/4/2003 11/12/2003 11/18/2003 11/25/2003 12/2/2003 12/9/2003 12/16/2003

February 2009

TSS (mg/L) 13 8 11 18 11 10 10 9 6 3 3 6 5 4 3 5 4 7 7 7 5 5 5 1 3 6 5 5 7 8 5 13

FC Amm DO WT (cfu/100 Dis. N TP mL) (mg/L) (mg/L) pH (mg/L) (*C) 7.6 300 0.11 7.6 820 0.77 7.5 540 0.08 7.6 9.3 18.5 560 0.07 2.15 7.5 7.8 20.5 500 0.63 7.6 10.0 21 400 0.06 7.6 8.6 19 1060 1.25 7.6 9.0 21 780 2.09 7.7 320 0.11 1.85 7.6 9.8 22 460 0.05 7.6 500 0.06 7.4 800 0.09 7.6 540 0.07 2.90 7.6 160 0.05 7.6 320 0.07 7.5 6.0 21.5 580 0.07 7.6 340 0.04 7.6 6.8 18 340 0.06 2.40 7.5 8.5 18 260 0.07 7.6 7.8 18.5 440 0.07 7.6 9.1 19 720 0.10 7.6 200 0.06 2.30 7.7 240 0.09 7.8 500 0.06 7.7 8.6 18 380 0.07 7.7 9.0 14 80 0.07 2.55 7.7 140 0.08 7.7 20 0.07 7.6 140 0.08 7.6 380 0.09 2.50 7.7 60 0.12 7.6 9.0 12.5 240 0.10

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date 12/22/2003 12/29/2003 1/6/2004 1/13/2004 1/20/2004 1/27/2004 2/3/2004 2/10/2004 2/17/2004 2/24/2004 3/2/2004 3/9/2004 3/16/2004 3/23/2004 3/30/2004 4/6/2004 4/13/2004 4/20/2004 4/27/2004 5/4/2004 5/11/2004 5/18/2004 5/25/2004 6/1/2004 6/8/2004 6/15/2004 6/22/2004 7/6/2004 7/13/2004 7/20/2004 7/27/2004 8/3/2004

Q TSS (cfs) (mg/L) 25.5 3 25.5 6 22.0 22 21.5 22 21.5 25 20.8 28 23.0 19 23.0 24 27.0 32 23.5 21 24 18 18.0 34 18.0 20 20.0 27 24.8 20 68.0 22 18.0 7 52.5 22 25.5 13 54.0 20 41.0 16 35.0 8 69.0 13 28.0 5 28.8 10 23.0 6 79.0 6 61.0 3 50.3 5 64.0 5 46.5 3

FC Amm DO WT (cfu/100 Dis. N TP mL) (mg/L) (mg/L) pH (mg/L) (*C) 8.0 20 0.07 8.0 220 0.09 8.0 9.5 9 180 0.07 0.66 8.0 360 0.07 8.0 260 0.07 8.0 380 0.08 8 160 0.08 0.52 8.0 320 0.09 7.9 420 0.15 8.0 760 0.11 8.0 220 0.08 0.81 8.0 60 0.05 8.1 10.4 16 80 0.09 8.1 11.0 17 260 0.06 8.1 10.6 16 220 0.05 8.1 280 0.10 0.89 7.9 8.0 13 40 0.05 7.9 9.8 15 <20 0.16 8.0 340 0.07 7.9 9.6 18.5 980 0.09 0.84 7.9 9.6 13 800 0.10 7.9 400 0.10 8.0 580 0.15 7.9 460 0.07 8.0 660 0.06 0.76 8.0 9.8 19 800 0.14 8.0 10.2 20.5 640 0.12 7.9 1133 0.08 0.46 7.9 10.2 20 880 0.06 7.8 9.5 21.5 0.27 7.8 800 0.05 7.8 980 0.06 0.52

165

Date 12/22/2003 12/29/2003 1/6/2004 1/13/2004 1/20/2004 1/27/2004 2/3/2004 2/10/2004 2/17/2004 2/24/2004 3/2/2004 3/9/2004 3/16/2004 3/23/2004 3/30/2004 4/6/2004 4/13/2004 4/20/2004 4/27/2004 5/4/2004 5/11/2004 5/18/2004 5/25/2004 6/1/2004 6/8/2004 6/15/2004 6/22/2004 7/6/2004 7/13/2004 7/20/2004 7/27/2004 8/3/2004

February 2009

TSS (mg/L) 9 12 24 19 21 24 18 17 22 16 17 17 22 19 19 11 21 7 19 8 13 12 13 11 7 11 10 5 4 6 4 4

FC Amm DO WT (cfu/100 Dis. N TP mL) (mg/L) (mg/L) pH (mg/L) (*C) 7.7 80 0.15 7.7 80 0.08 7.8 9.0 10 20 0.08 1.85 7.5 340 0.11 7.7 240 0.07 7.6 720 0.09 7.6 40 0.08 2.95 7.5 80 0.16 7.6 280 0.08 7.6 220 0.17 7.6 220 0.05 2.80 7.7 80 0.05 7.6 9.4 16 140 0.09 7.8 10.1 18 400 0.11 7.9 9.5 16.5 300 0.05 7.7 200 0.09 2.70 7.7 9.3 15 <20 0.07 7.7 9.0 16 140 0.08 7.8 380 0.07 7.8 9.5 19.5 380 0.08 2.90 7.7 9.0 14.5 540 0.10 7.7 540 0.09 7.7 320 0.15 7.7 480 0.07 7.7 120 0.07 2.65 7.8 9.0 19 780 0.13 7.7 9.5 21 460 0.11 7.7 833 0.09 1.30 7.8 9.6 21 460 0.07 7.6 8.8 22 0.20 7.7 560 0.05 7.7 840 0.06 2.45

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date 8/10/2004 8/17/2004 8/24/2004 8/31/2004 9/7/2004 9/14/2004 9/21/2004 9/28/2004 10/5/2004 10/12/2004 10/19/2004 10/26/2004 11/2/2004 11/9/2004 11/16/2004 11/23/2004 11/30/2004 12/7/2004 12/14/2004 12/21/2004 12/28/2004 1/4/2005 1/11/2005 1/18/2005 1/25/2005 2/1/2005 2/8/2005 2/15/2005 2/22/2005 3/1/2005 3/8/2005 3/15/2005

FC Amm Q TSS DO WT (cfu/100 Dis. N TP mL) (mg/L) (mg/L) (cfs) (mg/L) pH (mg/L) (*C) 60.0 4 7.7 1500 1.18 72.0 3 7.7 833 0.11 89.0 3 7.8 767 0.07 57.0 3 7.8 1220 0.12 77.0 1 7.8 433 0.06 0.54 74.0 1 7.8 500 0.04 95.0 2 7.8 9.1 16 200 0.28 79.0 2 7.8 9.1 17.5 367 0.22 75.0 2 7.8 580 0.05 0.52 70.0 1 7.9 9.7 14 280 0.06 51.0 <1 7.9 780 0.12 50.3 1 7.9 280 0.11 45.0 2 8.0 300 0.04 0.70 46.5 <1 7.9 1200 0.87 43.0 2 7.9 280 0.06 39.5 <1 8.0 120 0.06 38.5 3 8.0 10.2 11 280 0.08 38.5 4 8.0 340 0.10 0.87 36.3 7 7.9 4467 1.47 32.0 4 8.0 200 0.32 30.3 9 8.0 340 0.23 26.0 8 8.0 TNTC 0.24 0.90 25.5 8 8.0 9.6 12 700 0.11 22.5 10 7.7 200 0.11 21.5 9 8.0 400 0.22 20.8 11 8.0 380 0.09 1.00 20.8 10 8.1 160 0.09 20.0 21 8.1 300 0.07 18.0 21 8.1 300 0.32 17.0 17 8.1 260 0.39 0.59 15.0 17 8.1 1560 0.07 15.0 20 8.1 11.2 14 200 0.14

166

Date 8/10/2004 8/17/2004 8/24/2004 8/31/2004 9/7/2004 9/14/2004 9/21/2004 9/28/2004 10/5/2004 10/12/2004 10/19/2004 10/26/2004 11/2/2004 11/9/2004 11/16/2004 11/23/2004 11/30/2004 12/7/2004 12/14/2004 12/21/2004 12/28/2004 1/4/2005 1/11/2005 1/18/2005 1/25/2005 2/1/2005 2/8/2005 2/15/2005 2/22/2005 3/1/2005 3/8/2005 3/15/2005

February 2009

TSS (mg/L) 5 4 <1 4 4 6 6 5 5 2 4 4 5 4 9 6 8 12 16 10 13 12 11 11 14 13 13 16 12 14 15 22

FC Amm DO WT (cfu/100 Dis. N TP mL) (mg/L) (mg/L) pH (mg/L) (*C) 7.6 633 0.86 7.6 633 0.11 7.6 333 0.08 7.6 640 0.14 7.7 233 0.05 2.25 7.7 233 0.05 7.7 9.2 16.5 167 0.30 7.7 9.1 18.5 133 0.20 7.7 400 0.06 2.15 7.8 8.8 16 220 0.06 7.7 420 0.14 7.8 120 0.17 7.8 140 0.16 2.80 7.7 820 0.52 7.8 260 0.16 7.8 120 0.09 7.7 8.6 12 280 0.09 7.7 220 0.10 3.55 7.7 2433 0.59 7.7 <33 0.20 7.9 300 0.09 7.8 TNTC 0.24 2.18 7.8 9.0 12.5 700 0.09 7.4 167 0.31 7.7 80 0.23 7.6 220 0.39 3.75 7.7 280 0.13 7.7 520 0.25 7.8 67 0.22 7.8 300 0.23 3.15 7.8 1020 0.08 7.8 9.9 15 67 0.09

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date 3/22/2005 3/29/2005 4/5/2005 4/12/2005 4/19/2005 4/26/2005 5/3/2005 5/10/2005 5/17/2005 5/24/2005 5/31/2005 6/7/2005 6/14/2005 6/21/2005 6/28/2005 7/5/2005 7/12/2005 7/19/2005 7/26/2005 8/2/2005 8/9/2005 8/16/2005 8/23/2005 8/30/2005 9/6/2005 9/13/2005 9/20/2005 9/27/2005 10/3/2005 10/11/2005 10/18/2005 10/25/2005

FC Amm Q TSS DO WT (cfu/100 Dis. N TP mL) (mg/L) (mg/L) (cfs) (mg/L) pH (mg/L) (*C) 15.5 14 8.0 260 0.11 17.0 40 7.9 700 0.28 14.0 18 8.0 367 0.30 0.62 18.0 22 7.9 367 0.13 22.0 17 7.9 8.9 11 320 0.10 20.0 10 7.8 200 0.18 7.5 2 7.8 260 0.83 0.38 19.0 11 7.8 8.7 13.5 600 0.39 19.0 12 7.8 9.2 16.5 3267 0.11 18.0 8 7.9 667 0.10 15.5 5 7.9 740 0.08 41.5 3 8.0 780 0.51 0.54 39.0 6 8.0 10.0 19 867 0.14 50.3 18 7.9 580 0.10 70.0 19 7.8 8.4 18 TNTC 0.19 41.0 3 7.9 767 0.12 0.50 70.0 4 7.8 900 0.11 47.5 1 7.8 9.9 21 700 0.09 58.3 1 7.8 433 0.06 71.0 2 7.8 467 0.07 0.38 77.0 <1 7.8 8.9 21.5 600 0.09 64.0 <1 7.8 8.8 20.5 233 0.06 66.0 <1 7.8 733 0.10 75.0 <1 7.8 9.6 18.5 300 0.12 77.0 <1 7.8 333 0.05 0.26 107.0 4 7.8 200 0.04 109.0 3 7.8 8.4 16.5 200 0.30 104.0 2 7.8 9.1 16.5 260 0.30 86.0 2 7.8 880 0.07 0.24 67.0 <1 8.0 240 0.07 62.0 <1 7.9 10.4 15 500 0.57 57.8 2 7.9 100 0.04

167

Date 3/22/2005 3/29/2005 4/5/2005 4/12/2005 4/19/2005 4/26/2005 5/3/2005 5/10/2005 5/17/2005 5/24/2005 5/31/2005 6/7/2005 6/14/2005 6/21/2005 6/28/2005 7/5/2005 7/12/2005 7/19/2005 7/26/2005 8/2/2005 8/9/2005 8/16/2005 8/23/2005 8/30/2005 9/6/2005 9/13/2005 9/20/2005 9/27/2005 10/3/2005 10/11/2005 10/18/2005 10/25/2005

February 2009

TSS (mg/L) 11 28 17 27 18 9 5 9 12 7 20 4 6 11 15 4 4 4 3 2 3 3 2 <1 3 4 5 4 5 4 4 8

FC Amm DO WT (cfu/100 Dis. N TP mL) (mg/L) (mg/L) pH (mg/L) (*C) 7.7 160 0.12 7.6 500 0.23 7.8 233 0.32 3.05 7.8 1267 0.14 7.8 8.7 13 400 0.18 7.6 120 0.13 7.4 100 0.09 4.6 7.6 8.6 15.5 1000 0.16 7.7 8.7 17.5 2367 0.14 7.7 333 0.06 7.6 360 0.08 7.7 660 0.19 2.50 7.7 9.6 20 500 0.07 7.6 160 0.13 7.5 7.8 19.5 1320 0.07 7.6 367 0.14 2.50 7.7 600 0.35 7.7 8.9 22.5 380 0.15 7.6 500 0.06 7.7 300 0.07 2.85 7.6 7.1 24 333 0.12 7.6 7.9 22 300 0.17 7.6 233 0.26 7.8 8.2 20 300 0.18 7.6 233 0.13 2.30 7.6 160 0.28 7.5 7.3 18.5 140 0.13 7.6 8.4 18 300 0.30 7.6 440 0.29 1.9 7.8 140 0.05 7.7 8.4 17.5 133 0.20 7.6 140 0.06

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date 11/1/2005 11/8/2005 11/15/2005 11/22/2005 11/29/2005 12/6/2005 12/13/2005 12/19/2005 12/27/2005 1/3/2006 1/10/2006 1/16/2006 1/24/2006 1/31/2006 2/7/2006 2/14/2006 2/21/2006 2/28/2006 3/7/2006 3/14/2006 3/21/2006 3/28/2006 4/4/2006 4/11/2006 4/17/2006 4/25/2006 5/2/2006 5/9/2006 5/16/2006 5/23/2006 5/30/2006 6/6/2006

FC Amm Q TSS DO WT (cfu/100 Dis. N TP mL) (mg/L) (mg/L) (cfs) (mg/L) pH (mg/L) (*C) 62.0 <1 8.0 100 0.08 0.22 61.0 <1 7.9 660 0.03 50.3 <1 8.0 40 0.26 55.0 1 8.0 60 0.16 53.3 <1 8.0 10.0 10.5 50 0.35 50.3 <1 8.0 120 0.15 0.20 41.0 2 8.0 40 0.04 44.0 <1 8.0 80 0.09 59.0 4 7.9 60 0.36 68.0 5 7.9 20 0.121 62.0 8 8.0 8.3 11 20 0.08 0.24 56.0 4 8.0 40 0.08 50.3 3 8.1 80 0.11 41.0 11 8.0 10.0 10 260 0.17 40.5 11 8.0 10.0 11 680 0.02 0.22 39.5 7 8.0 11.0 10.6 440 0.07 37.7 13 8.0 10.9 10 260 0.04 37.7 16 8.0 240 0.11 34.0 8 8.0 120 0.07 0.19 32.0 13 7.9 120 0.06 30.3 13 8.1 11.8 13 3200 0.08 27.0 14 7.9 12.0 15 60 0.08 39.0 21 7.8 180 0.11 0.27 75.0 10 7.9 11.0 10 160 0.05 63.0 14 7.9 11.6 12.5 140 0.05 64.0 10 7.9 10.6 13.5 520 0.07 36.3 6 7.9 11.0 15.0 520 0.04 0.188 61.0 10 7.8 11.0 15 760 0.05 45.0 10 7.8 9.6 19 900 0.07 72.0 18 7.8 2660 0.07 73.0 14 7.8 840 0.31 51.5 11 7.8 1640 0.130 0.32

168

Date 11/1/2005 11/8/2005 11/15/2005 11/22/2005 11/29/2005 12/6/2005 12/13/2005 12/19/2005 12/27/2005 1/3/2006 1/10/2006 1/16/2006 1/24/2006 1/31/2006 2/7/2006 2/14/2006 2/21/2006 2/28/2006 3/7/2006 3/14/2006 3/21/2006 3/28/2006 4/4/2006 4/11/2006 4/17/2006 4/25/2006 5/2/2006 5/9/2006 5/16/2006 5/23/2006 5/30/2006 6/6/2006

February 2009

TSS (mg/L) 1 <1 6 10 4 5 8 7 6 10 10 6 33 17 21 20 9 12 14 12 20 12 16 8 13 8 18 18 9 15 11 12

FC Amm DO WT (cfu/100 Dis. N TP mL) (mg/L) (mg/L) pH (mg/L) (*C) 7.7 120 0.04 3.15 7.6 380 0.12 7.7 220 0.24 7.8 100 0.13 7.7 9.2 12 60 0.52 7.6 40 0.14 2.45 7.7 100 0.08 7.6 80 0.09 7.7 80 0.24 7.7 120 0.12 7.7 8.7 12 140 0.10 2.10 7.6 0.07 7.6 60 0.24 7.9 10.0 12 100 0.13 7.6 8.9 13 460 0.07 1.60 7.7 9.1 12.5 280 0.12 7.8 10.0 12 80 0.14 7.7 140 0.06 7.7 320 0.22 2.35 7.6 120 0.19 7.6 10.6 14 1180 0.14 7.8 11.5 15 20 0.10 7.4 440 0.10 3.50 7.6 10.0 12.0 40 0.05 7.5 11.2 13.5 120 0.05 7.6 10.0 15.0 420 0.16 7.2 10 16.5 280 0.53 6.40 7.4 10.5 16.0 640 0.06 7.5 9.8 20 660 0.05 7.6 1880 0.06 7.6 960 0.23 7.6 1480 0.213 2.75

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date 6/13/2006 6/20/2006 6/27/2006 7/4/2006 7/11/2006 7/18/2006 7/25/2006 8/1/2006 8/8/2006 8/15/2006 8/22/2006 8/29/2006 9/5/2006 9/12/2006 9/19/2006 9/26/2006 10/3/2006 10/10/2006 10/17/2006 10/24/2006 10/31/2006 11/7/2006 11/14/2006 11/21/2006 11/28/2006 12/5/2006 12/12/2006 12/19/2006 12/26/2006 1/2/2007 1/9/2007 1/16/2007

Q TSS DO (cfs) (mg/L) pH (mg/L) 69.0 12 7.9 10.4 85.0 7 7.8 81.0 <1 7.7 66.0 4 7.8 51.5 5 7.7 53.3 2 7.8 12.0 67.0 3 7.7 82.0 3 7.7 93.0 7 7.7 9.2 77.0 6 7.6 10.0 100.0 6 7.6 77.0 5 7.7 70.0 3 7.9 21.5 3 7.7 40.0 1 7.7 40.0 1 7.8 36.3 <1 7.8 70.0 4 7.8 10.2 58.3 1 8.0 39.5 2 8.0 37.0 1 8.0 37.0 2 8.0 37.7 2 7.8 35.0 <1 7.8 31.0 8 8.0 9.0 28.8 <1 7.8 30.3 <1 8.1 28.8 4 8.2 28.0 2 8.2 26.0 5 7.9 25.5 3 8.0 10.8 23.0 6 7.9

WT (*C) 17.5

20.5

20.0 20.0

14.0

11

12.0

FC (cfu/100 mL) 1260 400 760 620 920 640 280 340 280 280 360 440 220 280 100 280 460 80 80 170 180 40 140 60 70 40 100 20 30

Amm Dis. N TP (mg/L) (mg/L) 0.089 0.05 0.11 0.06 0.07 0.39 0.06 0.05 0.07 0.31 0.24 0.09 0.18 0.03 0.10 0.25 0.06 0.07 0.04 0.08 0.16 0.06 0.19 0.05 0.21 0.04 0.14 0.44 0.51 0.04 0.14 0.05 0.05 0.13 0.04 0.05 0.21 0.62

169

Date 6/13/2006 6/20/2006 6/27/2006 7/4/2006 7/11/2006 7/18/2006 7/25/2006 8/1/2006 8/8/2006 8/15/2006 8/22/2006 8/29/2006 9/5/2006 9/12/2006 9/19/2006 9/26/2006 10/3/2006 10/10/2006 10/17/2006 10/24/2006 10/31/2006 11/7/2006 11/14/2006 11/21/2006 11/28/2006 12/5/2006 12/12/2006 12/19/2006 12/26/2006 1/2/2007 1/9/2007 1/16/2007

February 2009

TSS (mg/L) 10 6 2 5 3 3 3 6 5 4 3 5 3 3 3 4 <1 5 5 6 2 6 8 9 9 7 5 5 6 6 10 10

FC Amm DO WT (cfu/100 Dis. N TP mL) (mg/L) (mg/L) pH (mg/L) (*C) 7.6 8.8 19.0 780 0.114 7.6 280 0.30 7.7 0.11 7.8 800 0.09 7.6 420 0.11 1.70 7.6 9.0 22.0 420 0.06 7.6 340 0.09 7.6 440 0.07 1.95 7.6 8.0 22.0 220 0.07 7.5 8.5 21.5 140 0.06 7.6 180 0.17 7.6 360 0.04 7.7 440 0.20 1.70 7.6 480 0.31 7.6 260 0.07 7.6 100 0.06 7.6 0.22 238 7.6 9.6 16 280 0.05 7.8 200 0.04 7.8 200 0.05 7.8 20 0.22 7.7 100 0.07 2.55 7.6 100 0.27 7.6 40 0.48 8.0 8.5 13 80 0.05 7.8 140 2.35 7.8 50 0.06 7.7 0.05 7.9 20 0.05 7.7 90 0.04 7.7 9.2 13.5 90 0.04 3.00 7.7 150 0.18

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date 1/23/2007 1/30/2007 2/6/2007 2/13/2007 2/20/2007 2/27/2007 3/6/2007 3/13/2007 3/20/2007 3/27/2007 4/3/2007 4/10/2007 4/17/2007 4/24/2007 5/1/2007 5/8/2007 5/15/2007 5/22/2007 5/29/2007 6/5/2007 6/12/2007 6/19/2007 6/26/2007 7/3/2007 7/10/2007 7/17/2007 7/24/2007 7/31/2007 8/7/2007 8/14/2007 8/21/2007 8/28/2007

FC Amm Q TSS DO WT (cfu/100 Dis. N TP mL) (mg/L) (mg/L) (cfs) (mg/L) pH (mg/L) (*C) 23.5 7 7.8 60 0.05 23.5 2 7.9 10.8 10.0 80 0.06 23.0 3 7.8 30 0.14 0.13 24.0 4 7.9 70 0.03 25.5 9 8.0 100 0.03 24.0 2 7.9 120 0.08 23.5 2 7.9 720 0.05 0.21 22.5 8 7.8 200 0.06 23.5 4 8.0 1780 0.15 20.8 3 7.9 40 0.11 24.0 14 7.9 100 0.12 0.50 87.0 14 7.8 180 0.12 27.0 6 7.8 140 0.05 30.0 8 8.1 220 0.09 35.0 7 8.0 460 0.05 0.75 38.0 5 7.8 11 19 230 0.04 54.0 6 7.9 460 0.06 57.0 6 7.9 430 0.08 49.0 4 7.9 580 0.05 47.0 5 7.8 380 0.14 0.46 60.0 2 7.6 480 0.04 47.0 3 7.7 1540 0.17 37.0 16 7.6 260 0.34 43.0 2 7.7 400 0.11 41.0 4 7.6 600 0.04 0.68 9.0 1 7.7 160 0.04 3.0 <1 7.5 80 0.03 2.0 <1 7.5 340 0.04 1 7.8 220 0.13 0.61 3 7.7 400 0.09 36.0 <1 7.7 360 0.10 66.0 2 7.8 460 0.03

170

Date 1/23/2007 1/30/2007 2/6/2007 2/13/2007 2/20/2007 2/27/2007 3/6/2007 3/13/2007 3/20/2007 3/27/2007 4/3/2007 4/10/2007 4/17/2007 4/24/2007 5/1/2007 5/8/2007 5/15/2007 5/22/2007 5/29/2007 6/5/2007 6/12/2007 6/19/2007 6/26/2007 7/3/2007 7/10/2007 7/17/2007 7/24/2007 7/31/2007 8/7/2007 8/14/2007 8/21/2007 8/28/2007

February 2009

TSS (mg/L) 13 9 13 11 7 9 13 14 10 8 9 15 8 8 5 6 3 5 4 5 4 8 6 3 5 1 2 3 2 3 <1 2

FC Amm DO WT (cfu/100 Dis. N TP mL) (mg/L) (mg/L) pH (mg/L) (*C) 7.7 110 0.12 7.6 9.8 12.0 40 0.08 7.4 50 0.06 2.70 7.4 60 0.21 7.6 60 0.21 7.7 70 0.12 7.6 320 0.05 3.70 7.5 130 0.06 7.7 1300 0.15 7.6 7.6 180 0.05 3.60 7.7 80 0.04 7.7 140 0.06 7.7 120 0.18 7.8 280 0.08 2.50 7.6 10.4 19.0 160 0.06 7.7 310 0.07 7.6 340 0.07 7.6 260 0.09 7.5 360 0.14 3.00 7.5 440 0.07 7.7 180 0.20 7.5 500 0.24 7.4 260 0.11 7.5 500 0.09 3.02 7.6 140 0.10 7.5 220 0.09 7.4 220 0.14 7.5 180 0.09 2.70 7.6 380 0.08 7.6 300 0.09 7.6 180 0.12

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date 9/4/2007 9/11/2007 9/18/2007 9/25/2007 10/2/2007 10/9/2007 10/16/2007 10/23/2007 10/30/2007 11/6/2007 11/13/2007 11/20/2007 12/27/2007 12/4/2007 12/11/2007 12/18/2007 12/26/2007

FC Amm Q TSS DO WT (cfu/100 Dis. N TP mL) (mg/L) (mg/L) (cfs) (mg/L) pH (mg/L) (*C) 50.0 5 7.8 1420 0.23 39.0 2 7.8 160 0.34 0.50 41.0 <1 7.7 100 0.03 49.0 1 7.7 190 0.09 57.0 3 7.8 360 0.03 0.68 48.0 1 7.6 240 0.02 46.0 <1 7.7 280 0.06 39.0 10 7.8 90 0.08 36.0 2 7.9 8.6 16 320 0.03 7.7 110 0.08 11.6 <5 7.9 250 0.10 7.9 8.1 12.5 110 0.08 7.8 210 0.11 8.0 11.0 14 50 0.07 11.6 <5 7.9 80 0.05 8.0 100 0.14 8.0 80 0.03

Date 9/4/2007 9/11/2007 9/18/2007 9/25/2007 10/2/2007 10/9/2007 10/16/2007 10/23/2007 10/30/2007 11/6/2007 11/13/2007 11/20/2007 12/27/2007 12/4/2007 12/11/2007 12/18/2007 12/26/2007

February 2009

TSS (mg/L) 3 4 3 2 3 4 3 3 3 3 4 5 4 13 21 12 18

FC Amm DO WT (cfu/100 Dis. N TP mL) (mg/L) (mg/L) pH (mg/L) (*C) 7.7 860 0.15 7.6 200 0.14 2.90 7.6 100 0.07 7.7 160 0.04 7.5 160 0.08 2.80 7.4 180 0.03 7.5 230 0.06 7.5 60 0.10 7.5 8.7 17 90 0.05 7.5 160 0.10 7.5 660 0.07 3.30 7.6 6.4 14.5 330 0.07 7.5 100 0.28 7.6 8.5 15 60 0.06 7.6 110 0.07 3.05 7.6 80 0.07 7.6 60 0.05

Q = discharge; cfs = cubic feet per second; TSS = Total Suspended Sediment; mg/L = milligrams per liter; DO = Dissolved Oxygen; WT = Water Temperature; *C = degrees Celsius; FC = Fecal Coliform; cfu = colony-forming units; Amm Dis. = Dissolved Ammonia; TP = Total Phosphorus; TNTC = too numerous to count

171

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table C- 4. Reported results of data collected by the Bureau of Reclamation from locations in the Lower Boise River subbasin between 1999 and 2008.

Bureau of Reclamation

Site ID

Date

E. coli TSS P Q WT DO SpC Turbidity (cfu/100 (mg/ (mg/ mL) L) L) (cfs) pH (*C) (mg/L) (uS/cm3) (NTU)

OP Dis. (mg/ Amm L) (mg/L)

Nitrate/ Nitrite Dis. (mg/L)

Indian Creek at Reservoir Inlet 0

7.6

5.3

12

88

6

BOI142 3/15/1999 880

7.8

4.2

11.2

90

3

*Nondetect *Nondetect

BOI142 BOI142 BOI142 BOI142

7.6 7.5 7.8 7.9

5.7 9.1 14.9 15.9

10.8 10.8 9.9 7

84 54 69 70

10 6 3 2

62 28 38 14

8.0

16.8

10

76

2

2

BOI142 2/23/1999

5/17/1999 880 6/15/1999 7/12/1999 8/17/1999

BOI142 9/21/1999

14 0.025 0.014 2 0.012 0.007 12 6 8 4

0.051 0.032 0.026 0.015

0.019 0.016 0.015 0.01

0.022 0.011

0.02 *Nondetect *Nondetect 0.01 0.01 0.01 *Nondetect

0.2 0.16 0.24 0.13 0.13 0.14 0.15

Indian Creek above New York Canal BOI140 2/23/1999 738 7.25 BOI140 BOI140 BOI140 BOI140 BOI140 BOI140

3/15/1999 880 7.25 4/6/1999 880 7.6 5/17/1999 612 7.83 6/15/1999 7.5 7/12/1999 7.5 8/17/1999 7.8

BOI140 9/21/1999

7.5

4.2

12.1

87

5

4 5.5 8.4 11.1 13.1 15

10.8 10.2 10.4 10.8 9.8 7.9

89 83 63 49 56 60

3 9 5 6 2 2

16.9

10.7

66

2

*Nondetect *Nondetect 26 8 6 16 6 *Nondetect

172

0.031 0.022 1 9 4 6 2 2

0.016 0.049 0.028 0.025 0.017 0.011

4

0.036

*Non-detect *Non0.007 detect 0.02 0.01 0.012 0.01 0.012 0.01 0.008 0.02 0.007 0.01 *Non0.008 detect

0.11 0.18 0.24 0.11 0.1 0.05 0.07 0.07

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Site ID

Date

BOI320

3/5/2000

February 2009

E. coli TSS P Q WT DO SpC Turbidity (cfu/100 (mg/ (mg/ mL) L) L) (cfs) pH (*C) (mg/L) (uS/cm3) (NTU)

OP Dis. (mg/ Amm L) (mg/L)

Nitrate/ Nitrite Dis. (mg/L)

Ninemile Creek near mouth 7

11.5

430

20

115

Boise River at Eckert Road BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125

4/19/2001 7.63 5/10/2001 7.7 6/28/2001 7.45 7/20/2001 7.47 8/16/2001 7.62 9/14/2001 7.89 10/30/2001 7.9 11/29/2001 7.9 12/20/2001 7.46 1/28/2002 8.19 2/27/2002 7.85 3/21/2002 8.21 4/30/2002 7.3 5/31/2002 8.04 6/28/2002 8.01 7/30/2002 7.67 8/30/2002 7.92 9/30/2002 7.81 10/29/2002 300 7.49 11/29/2002 7.51 11/29/2002 12/26/2002 7.08 1/28/2003 8.02 2/26/2003 8.03 3/19/2003 8.05 4/18/2003 8.29 5/31/2003 7.77

6.5 7.1 12.1 14.4 18.2 18.2 12.1 4.9 5.3 2.1 2.4 5.9 6.4 10.9 12.6 15.6 17.5 15 9.1 5.4 2.8 4.2 2.9 4.6 7.3 8.6

13.4 12.6 8.7 9.6 9.2 8 9.8 11.7 10.4 12.4 12.5 12.5 12 11.5 10.5 8.5 9.3 8.9 9.9 11.3 11.3 10 11.4 10.9 12.4 10.1

94 85 73 73 73 82 93 89 91 95 98 66 54 62 71 74 92 93 58 66 88 90 86 69

3 2 1 2 2 4 4 4 3 4 3 3 5 4 3 1 2 3 6 5 5 3 2 2 2 5 2

2 6 4 3 2 1 2 2 4 3 2 1 4 2 2 4 4 3 2 3 5 5 1

173

0.26 0.137

0.15

2.74

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Site ID BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125

Date 6/30/2003 7/7/2003 7/18/2003 7/24/2003 7/28/2003 8/4/2003 8/14/2003 8/22/2003 8/28/2003 9/5/2003 9/11/2003 9/18/2003 9/25/2003 9/30/2003

BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125 BOI125

10/9/2003 10/14/2003 10/22/2003 10/31/2003 11/6/2003 11/13/2003 11/21/2003 11/25/2003 12/5/2003 12/11/2003 12/24/2003 12/31/2003 1/9/2004 1/9/2004

Q (cfs) pH 8.46 7.86 6.96 8.08 7.65 7.45 7.7 8.37 7.67 7.64 8 8.06 8.11 7.73

7.6 7.49 7.51 7.86 7.71 7.75 7.94 7.99 8.16 7.9 7.74 7.54 7.87

WT DO (*C) (mg/L) 13.7 9.7 12.4 9.5 21.3 8.7 14.4 9.8 14.8 9.1 15.3 8.6 16.8 9.1 18.7 9.6 17.4 8 18.9 9.1 14.2 9.4 17.5 9.8 16.8 10 15.4 9.5

16.3 12.8 12.5 9.2 6.7 5.9 5.5 5 7.2 5.5 4.3 2.6 3

7.7 8.2 10 10.7 10.8 12.8 12 12.3 12.5 12 12 12.8 12.5

E. coli TSS P SpC Turbidity (cfu/100 (mg/ (mg/ mL) L) L) (uS/cm3) (NTU) 49 4 5 47 4 7 73 1 3 46 2 3 47 2 2 54 2 3 64 1 2 69 1 <1 71 2 3 75 12 14 74 5 8 75 7 8 76 8 10 77 2 4 15verified by 82 10 rerun 80 10 18 85 8 15 85 9 10 84 7 11 86 8 13 84 7 5 84 5 5 83 4 5 83 4 6 83 4 4 82 5 3 85 4 6 4 5

174

February 2009

OP Nitrate/Nit Dis. (mg/ Amm rite Dis. L) (mg/L) (mg/L)

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Q WT DO Site ID Date (cfs) pH (*C) (mg/L) BOI125 1/15/2004 7.81 1.2 13.3 BOI125 1/23/2004 7.85 1.7 14.7 BOI125 1/23/2004 BOI125 1/29/2004 7.74 2.3 12.4 BOI125 2/5/2004 7.94 2.6 12.7 BOI125 2/12/2004 7.95 1 13.1 BOI125 2/19/2004 8.03 2.8 12.6

BOI125 BOI125 BOI125 BOI125 BOI125 BOI125

3/29/2004 4/23/2004 5/27/2004 7/10/2004 8/12/2004 9/17/2004

7.62 6.2 8.08 8.7 7.62 9.9 7.38 12.9 7.87 17.6 8.21 17.8

12.9 12.1 10.3 8 9 8.4

February 2009

E. coli TSS P SpC Turbidity (cfu/100 (mg/ (mg/ mL) L) L) (uS/cm3) (NTU) 85 7 6 85 4 4 4 4 85 6 6 87 3 5 88 3 4 88 4 6 5confir med by 91 3 rerun 84 5 6 64 2 3 93 2 2 67 2 2 75 3 3

Boise River below Lucky Peak Dam BOI101 10/29/2002

7

4

Boise River at Glenwood Bridge BOI106 2/14/2006 BOI106 2/14/2006

<4 <2

6

Boise River at Star Bridge BOI110 2/15/2006

< 10

175

8

OP Nitrate/Nit Dis. (mg/ Amm rite Dis. L) (mg/L) (mg/L)

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Boise River near Parma at County Bridge E. coli P Q WT DO SpC Turbidity (cfu/100 TSS (mg/ (cfs) pH (*C) (mg/L) (uS/cm3) (NTU) mL) (mg/L) L) Site ID Date BOI133 2/15/2006 70 22

OP Dis. (mg/ L)

Nitrate/N Amm itrite Dis. (mg/L) (mg/L)

Q = discharge; cfs = cubic feet per second; WT = Water Temperature; *C = degrees Celsius; DO = Dissolved Oxygen; mg/L = milligrams per liter; SpC = Specific Conductance; uS/cm3 = microSiemens per cubic centimeter; NTU = Nephelometric Turbidity Unit; cfu = colony-forming units; TSS = Total Suspended Sediment; P = Total Phosphorus; OP Dis. = Dissolved Ortho-Phosphorus; Amm = Ammonia; Nitrate/Nitrite Dis. = Dissolved Nitrate/Nitrate

176

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table C-5. Data collected by DEQ from locations in the Lower Boise River subbasin in 2008. DEQ 2008 Data Collection Reported Results Date

Time

Q (cfs)

AT (*C)

WT (*C)

DO (mg/L)

pH

SpC (uS/cm3)

E. coli (cfu/100mL)

Amm Dis. (N mg/L)

OP Dis. (mg/L)

TP (mg/L)

SSC (mg/L)

Thurman Drain AU 005_06 5/13/08 6/24/08 7/30/08 9/4/08 10/21/08

8:30 8.3 8:45 4.2 9:30 21e 8:45 17.3e 9:25 5.6

18.7 18.9 18.9 5.56

14.1 20.75 21.58 27.7 12.93

8.25 9.97 10.33

7.78 7.55 7.22 6.27 7.98

215 304 234 263 289

9.7 101.2 111 16.1 2

0.061 0.06 0.072 0.16 0.009

0.043 0.0561 0.0207 0.051 0.022

0.119 0.0487 0.049 0.11 0.08

22 7.3 4.9 6.2 6.1

0.009 0.009

0.284 0.162

0.285 0.2

38 15

0.01

0.40

0.44

18

0.077 0.049 0.03 0.01

0.286 0.243 0.58 0.27

0.396 1 0.69 0.30

160 1200 7.9 9.9

0.009 0.039 0.009 0.01

0.016 0.646 0.015 0.01

0.057 0.706 0.026 0.02

9 5.3 4.9 4.9

0.2 0.04

0.17 0.186

0.495 0.17

W. Hartley Drain AU 005_06 6/24/08 7/30/08 9/4/08 10/21/08

12:35 15e 20.14 12:15 10e 23.9 11:00 road closed 12:05 5.09e 10

17.21 19.68 13.22

8.15

6.89 7.48

185 144

8.19

9.42

427

551 670 20.3

E. Hartley Drain AU 005_06 6/24/08 7/30/08 9/4/08 10/21/08

10:50 26e 11:00 19e 10:30 9.6e 11:20 11.01e

24.1 23.9

16.3 16.58

9.89

6.79 7.48

262 348

774.6 247

10

12.92

7.76

8.54

628

36.4

Sand Hollow, Oasis Rd AU 017_02 5/13/08 6/24/08 7/30/08 9/4/08 10/21/08

11:45 2.4 13:30 0.6e 13:20 0.45e 11:50 .25e 14:00 dry

25

11.5 18.38 21.54

10.34 10.09

7.49 6.16 5.42

47 70 117

13.4 298.3 118 387.3

Sand Hollow, Market Rd AU 017_03 5/13/08 13:25 6/24/08 14:30 17e

12.47 19.61

9.34

8.17 7.83

180 324

177

369.2 209.8

300 24

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date 7/30/08 9/4/08 10/21/08

Time Q (cfs) 14:30 45e 13:00 24e 14:15 9.89

AT (*C) 26.1

WT (*C) 19.36

DO (mg/L) 9.09

12.36

8.56

pH 7.16

February 2009

SpC E. coli Amm Dis. (N (uS/cm3) (cfu/100mL) mg/L) 245 1014 0.047 410.6 0.01 610 129.1 0.01

OP Dis. (mg/L) 0.166 0.20 0.23

TP (mg/L) 0.36 0.28 0.27

SSC (mg/L) 460 76 53

Indian Creek, Kings Rd AU 003a_04 5/13/08 14:30 10.3 6/24/08 15:30 22e 7/30/08 16:00 15e 9/4/08 14:30 13.09e 10/22/08 8:05 37.91

13.77 17.26

11.01

8.18 7.85

372 502

142.1 242

0.028 0.067

0.77 1.07

0.892 1.04

7 4.9

28.9

17.9

8.31

6.91

405

1.7

10.79

8.29

461 378.4 290.9

0.009 0.01 0.01

0.607 0.28 0.82

0.69 0.29 0.84

5 4.9 4.9

505

Q = discharge; cfs = cubic feet per second; AT = Air Temperature; *C = degrees Celsius; WT = Water Temperature; DO = Dissolved Oxygen; mg/L = milligrams per liter; SpC = Specific Conductance; uS/cm3 = microSiemens per cubic centimeter; cfu = colony-forming units; Amm. Dis. = Dissolved Ammonia; OP Dis. = Dissolved Ortho-Phosphorus; TP= Total Phosphorus; SSC - Suspended Sediment Concentration; e = Estimated

178

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table C-6. Aquatic life data collected by DEQ from Lower Boise River subbasin locations between 2003 and 2008. Assessment Unit BURP ID Location

003a_04 2003SBOIA051 Indian Creek at Robinson Road

Macroinvertebrates Date Measured: 2003-10-14

Name

Taxon Code

Coenagrionidae Baetis tricaudatus Tricorythodes sp. Simulium sp. Cryptochironomus sp. Paratendipes sp. Potthastia longimana gr. Turbellaria Nematoda Physa (Physella) sp. Ostracoda Sphaeriidae Potamopyrgus antipodarum Enchytraeidae Crangonyx sp. Eukiefferiella coerulescens gr. Limnodrilus hoffmeisteri Rhyacodrilus sp.

6 20 57 303 340 380 389 416 417 434 442 567 810 935 989 1005 1067 1135

Count

4 2 1 1 1 1 1 29 16 1 11 5 389 1 1 1 38 1

Fish Name

redside shiner sculpin

Count

21 1

179

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit

006_02

BURP ID

2003SBOIA050

Location

Mason Creek at Lakeview Park

Macroinvertebrates Date Measured: 2003-10-15

Name

Taxon Code

Baetis tricaudatus Cricotopus sp. Pentaneura sp. Polypedilum sp. Turbellaria Nematoda Ostracoda Sphaeriidae Potamopyrgus antipodarum Enchytraeidae Coenagrion/Enallagma sp. Crangonyx sp. Limnodrilus hoffmeisteri Nais variabilis Rhyacodrilus sp.

Count

20 333 384 386 416 417 442 567 810 935 969 989 1067 1115 1135

1 1 1 2 50 1 2 2 400 2 4 2 29 2 17

Fish Name

Count

northern squawfish redside shiner smallmouth bass sucker

2 12 1 6

180

February 2009

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Assessment Unit

010_03

BURP ID

2003SBOIA052

Location

February 2009

Fivemile Creek at Meridian Road

Macroinvertebrates Date Measured: 2003-10-14

Name

Taxon Code

Baetis tricaudatus Tricorythodes sp. Simulium sp. Cricotopus bicinctus gr. Cricotopus trifascia gr. Eukiefferiella claripennis gr. Orthocladius (Euorthocladius) sp. Turbellaria Nematoda Gyraulus sp. Pisidium sp. Ostracoda Acari Potamopyrgus antipodarum Limnodrilus hoffmeisteri Rhyacodrilus sp. Prostoma sp.

Count

20 57 303 334 339 348 371 416 417 431 435 442 453 810 1067 1135 1233

4 3 6 1 9 16 1 86 37 1 98 12 9 249 8 2 7

Fish Name northern squawfish redside shiner dace sucker

Count 1 43 16 3

181

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table C-7. Fish community data collected by the USGS from Lower Boise River subbasin locations between 2003 and 2008. Station Name

Date

% COLD

% COOL

11/17/2003 11/18/2003 11/18/2003 8/18/2004 11/19/2003 11/19/2003

20 53 61.3 24.8 99 83.5

80 47 38.4 74.1 0.9 15.5

Site ID

Lower Boise River below Eckert Road Lower Boise River above Lander Street WWTP Lower Boise River below Lander Street WWTP Boise River at Glenwood Bridge Lower Boise River above West Boise WWTP Lower Boise River below West Boise WWTP

4333571160800 4336571161321 4338281161459 13209500 4340121161823 4340301162020

% WARM

0 0.3 1.1 0.1 1

WWTP = wastewater treatment plant

Table C-8. Sediment load analysis of TMDL control locations for February and May 2008. Sediment Load Analysis

Location Lander Meridian Boise West Middleton Nampa Caldwell Star Notus

Date May-08 May-08 May-08 May-08 May-08 May-08 May-08 Feb-08

Q (cfs) 20 4.9 3 0.428 10.29 5.18 0.633 0.546

Constituent TSS TSS TSS TSS TSS TSS TSS TSS

Concentration (mg/L) 0.8 2 5.4 37 6 8 7 36

Coefficient 0.0027 0.0027 0.0027 0.0027 0.0027 0.0027 0.0027 0.0027

Q = discharge; cfs = cubic feet per second; mg/L = milligrams per liter; TSS = total suspended solids

182

Result (tons/day) 0.0432 0.0265 0.0437 0.0428 0.1667 0.1119 0.0120 0.0531

% Salmonids

20 47 61.3 24.8 89 83.5

Count

Number of Species

854 524 284 173 384 291

11 11 13 10 11 8

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table C-9. Daily maximum and average water temperature, in degrees Celsius, recorded by the City of Boise between 2003 and 2008. Date

BR at Parma BR at Middleton

BR at Eagle

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

01/01/03 01/02/03 01/03/03 01/04/03 01/05/03 01/06/03 01/07/03 01/08/03 01/09/03 01/10/03 01/11/03 01/12/03 01/13/03 01/14/03 01/15/03 01/16/03 01/17/03 01/18/03 01/19/03 01/20/03 01/21/03 01/22/03 01/23/03 01/24/03 01/25/03 01/26/03 01/27/03 01/28/03 01/29/03 01/30/03 01/31/03

6.23 6.54 7.78 7.94 7.63 6.54 5.61 4.98 4.83 5.29 6.08 6.86 8.40 8.86 8.24 7.01 6.54 6.23 6.23 6.54 6.39 6.23 7.78 7.63 8.40 9.17 9.64 8.86 8.09 8.86 9.79

5.88 6.22 6.99 7.56 7.13 6.00 5.16 4.71 4.73 5.04 5.64 6.29 7.56 8.60 7.52 6.59 6.14 6.16 6.10 6.28 6.21 6.03 6.70 7.26 8.03 8.73 9.32 7.94 7.60 8.33 9.21

5.48 5.79 7.35 7.19 6.57 5.79 5.17 4.08 4.08 4.70 5.48 6.10 7.81 7.96 7.04 6.10 5.94 5.32 5.79 5.48 5.01 5.32 6.87 6.87 7.64 8.57 8.72 7.80 7.18 7.96 9.18

5.06 5.35 6.27 6.61 5.98 4.90 4.22 3.69 3.77 4.04 4.76 5.44 6.89 7.63 6.23 5.35 5.19 5.23 5.17 5.25 4.90 4.88 5.60 6.24 7.04 7.93 8.28 7.02 6.47 7.36 8.35

6.72 7.03 8.12 8.12 7.50 6.72 6.10 5.47 5.47 6.10 6.88 7.50 8.42 8.42 7.81 6.88 6.88 6.72 7.03 6.57 6.41 6.41 7.65 7.65 8.58 9.04 8.88 7.96 7.81 8.42 9.35

5.89 6.32 7.06 7.31 6.71 5.85 5.29 4.88 4.96 5.34 5.83 6.32 7.60 8.03 6.82 6.15 6.20 6.15 6.06 6.05 5.84 5.83 6.58 6.87 7.67 8.16 8.41 7.30 6.83 7.78 8.51

5.60 5.76 7.16 7.00 6.38 5.60 4.98 4.51 4.67 5.13 5.76 6.07 7.46 7.31 6.69 5.76 5.76 5.60 5.60 5.44 5.13 5.13 6.84 6.69 7.31 7.62 7.77 6.84 6.53 7.31 7.93

183

4.87 5.27 6.12 6.25 5.66 4.73 4.19 3.78 4.05 4.37 4.83 5.17 6.50 7.00 5.71 4.97 5.00 4.95 4.83 4.82 4.60 4.66 5.64 5.82 6.46 6.85 7.35 6.10 5.56 6.62 7.27

4.79 4.94 6.19 5.88 5.41 4.63 4.16 3.69 3.84 4.16 4.79 5.26 6.66 6.51 5.57 4.94 4.94 4.47 4.79 4.16 4.01 4.16 6.19 5.88 6.19 6.66 7.13 6.03 5.72 6.35 7.13

4.12 4.40 5.29 5.37 4.84 3.86 3.32 2.92 3.22 3.49 4.01 4.34 5.67 6.11 4.85 4.09 4.10 4.04 4.03 3.92 3.69 3.82 4.89 4.94 5.53 5.96 6.54 5.19 4.66 5.71 6.35

4.88 4.73 5.97 5.51 5.35 4.57 4.26 3.95 3.95 3.95 4.57 4.73 6.13 5.82 5.35 4.73 4.88 4.11 4.73 3.95 3.95 3.95 5.97 5.35 5.51 5.97 5.82 5.51 5.19 5.51 6.59

3.96 4.16 5.00 5.03 4.53 3.71 3.31 3.07 3.32 3.46 3.81 4.16 5.23 5.51 4.46 3.84 3.91 3.88 3.76 3.74 3.51 3.69 4.56 4.55 4.99 5.47 5.59 4.55 4.32 5.10 5.73

4.85 4.69 5.01 4.85 4.85 4.69 4.69 4.54 4.38 4.22 4.38 4.38 4.54 4.38 4.69 4.38 4.38 4.07 4.38 4.07 4.22 4.07 4.54 4.54 4.22 4.38 4.22 4.54 4.38 4.38 4.69

4.57 4.52 4.65 4.62 4.54 4.40 4.28 4.21 4.10 4.11 4.14 4.17 4.29 4.26 4.23 4.11 4.08 4.04 4.03 3.94 3.95 3.91 4.07 4.01 4.07 4.16 4.15 4.09 4.04 4.15 4.33

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

02/01/03 02/02/03 02/03/03 02/04/03 02/05/03 02/06/03 02/07/03 02/08/03 02/09/03 02/10/03 02/11/03 02/12/03 02/13/03 02/14/03 02/15/03 02/16/03 02/17/03 02/18/03 02/19/03 02/20/03 02/21/03 02/22/03 02/23/03 02/24/03 02/25/03 02/26/03 02/27/03 02/28/03 03/01/03 03/02/03 03/03/03 03/04/03 03/05/03

9.79 8.09 7.63 7.48 6.23 5.92 5.92 5.92 6.39 7.17 7.17 7.48 7.32 9.33 9.17 8.71 8.56 9.02 7.78 8.86 9.79 9.02 8.24 6.54 6.86 6.86 7.48 6.86 8.40 8.71 9.48 8.56 8.24

9.36 7.22 7.05 6.76 5.71 5.15 4.95 5.06 5.31 5.92 6.11 6.36 6.98 8.19 8.50 8.36 7.95 8.02 7.11 7.91 8.83 8.48 7.42 5.65 5.35 5.65 6.27 6.13 6.95 7.34 8.42 7.92 7.49

8.88 7.18 6.41 6.72 5.79 4.86 5.17 5.17 5.63 6.41 6.56 6.72 6.41 8.42 8.11 7.96 8.42 7.33 7.03 7.64 8.42 8.26 7.03 6.10 6.10 6.41 7.03 6.10 7.80 8.11 8.11 7.49 7.03

8.13 6.14 5.59 5.55 4.56 3.88 3.76 3.97 4.06 4.75 4.92 5.24 5.89 6.98 6.93 7.30 7.13 6.62 5.89 6.61 7.38 7.07 5.81 4.51 4.24 4.62 5.34 5.05 5.95 6.20 7.00 6.38 6.15

9.04 7.65 7.03 7.50 6.26 6.11 6.26 6.57 6.57 7.19 7.19 7.34 7.19 8.57 8.42 8.42 9.03 7.81 7.50 7.81 8.27 8.27 7.81 6.73 7.03 7.34 7.65 6.73

8.30 6.48 6.28 6.47 5.47 5.04 5.03 5.13 5.16 5.80 5.89 6.08 6.64 7.26 7.13 7.70 7.47 7.04 6.41 7.05 7.55 7.26 6.34 5.40 5.36 5.72 6.25 5.85

8.42 7.96 7.50

7.80 7.04 6.93

7.93 6.07 5.76 6.07 5.13 4.67 5.13 4.98 5.29 6.07 6.07 6.38 5.91 7.00 7.16 7.16 7.16 6.69 6.38 6.53 7.16 6.53 6.53 5.60 5.76 6.22 6.53 5.44 7.00 7.31 7.31 6.69 6.38

184

7.18 5.18 4.81 4.98 4.05 3.66 3.75 3.81 3.88 4.58 4.62 4.91 5.35 6.02 5.88 6.42 6.08 5.71 5.11 5.70 6.29 5.96 5.07 4.17 4.10 4.49 4.94 4.47 5.21 5.41 6.23 5.80 5.65

6.82 5.41 4.79 4.79 4.16 4.32 4.32 4.16 4.47 5.26 5.41 5.57 4.94 6.19 6.35 6.03 6.19 5.72 5.57 5.57 6.35 6.03 5.57 4.94 5.26 5.72 5.72 4.63 6.03 6.51 6.82 6.19 5.41

6.31 4.38 3.88 4.05 3.20 2.89 2.95 3.03 3.10 3.83 3.84 4.08 4.43 5.16 5.03 5.57 5.24 4.84 4.24 4.74 5.38 5.10 4.23 3.36 3.34 3.75 4.12 3.62 4.40 4.64 5.34 4.80 4.50

5.97 5.04 4.73 5.04 4.11 4.42 4.42 4.26 4.57 5.19 5.19 5.35 4.57 5.97 5.97 5.35 6.44 5.35 5.04 5.19 5.51 5.82 5.19 4.88 5.04 5.35 5.35 4.42 5.82 6.13 5.82 5.82 4.88

5.62 3.84 3.68 3.79 3.08 2.91 2.94 2.98 3.03 3.59 3.60 3.88 4.18 4.73 4.66 4.92 4.73 4.29 3.80 4.28 4.76 4.62 3.80 3.22 3.23 3.52 3.79 3.37 4.04 4.24 4.68 4.37 4.02

4.38 4.54 4.22 4.38 4.07 4.07 4.07 3.91 3.91 3.91 3.91 3.91 3.75 3.91 3.91 3.91 3.91 3.91 3.91 3.75 3.91 4.07 4.07 4.07 3.91 3.91 3.91 3.75 4.07 3.91 3.91 3.75 3.75

4.21 4.14 4.01 4.02 3.96 3.79 3.70 3.67 3.57 3.57 3.54 3.55 3.54 3.66 3.64 3.73 3.68 3.67 3.63 3.65 3.70 3.70 3.71 3.68 3.51 3.46 3.47 3.52 3.67 3.55 3.61 3.54 3.53

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

03/06/03 03/07/03 03/08/03 03/09/03 03/10/03 03/11/03 03/12/03 03/13/03 03/14/03 03/15/03 03/16/03 03/17/03 03/18/03 03/19/03 03/20/03 03/21/03 03/22/03 03/23/03 03/24/03 03/25/03 03/26/03 03/27/03 03/28/03 03/29/03 03/30/03 03/31/03 04/01/03 04/02/03 04/03/03 04/04/03 04/05/03 04/06/03 04/07/03

8.56 9.02 9.17 9.17 11.34 12.28 13.67 12.74 13.52 12.59 12.90 12.43 11.34 12.43 12.90 12.12 11.50 12.43 12.90 11.50 11.34 11.04 12.12 12.90 13.98 14.76 14.13 12.90 10.42 10.57 11.81 10.42 12.28

7.73 8.25 8.54 8.57 9.82 11.04 12.19 12.11 12.34 11.45 11.16 10.96 9.86 10.30 11.26 11.19 11.19 10.96 10.89 10.47 10.27 9.65 9.82 10.82 11.92 13.22 13.30 11.43 9.65 9.46 10.14 9.67 9.73

7.80 8.42 8.11 8.42 11.36 11.51 11.20

6.70 7.47 7.38 7.40 9.30 9.94 10.04

12.43 10.89 12.28 11.97 11.20 11.97 11.82 11.36 10.58 12.28 11.97 9.96 10.74 10.89 11.51 12.28 13.67 14.29 13.36 11.51 9.96 9.80 10.74 9.80 12.28

11.41 10.25 10.14 10.00 9.14 9.46 10.13 9.90 10.06 10.19 9.91 9.31 9.42 8.85 9.12 9.89 11.23 12.63 12.34 10.44 8.85 8.51 9.08 8.75 9.17

8.73 8.73 8.58 9.97 10.59 11.21 12.45 11.36 11.98 10.75 12.14 11.67 10.91 11.52 11.36 10.91 10.44 12.45 11.83 10.13 10.75 10.91 10.91 11.83 12.76 13.23 12.61 10.91 9.66 9.82 10.59 9.51 11.67

7.64 7.89 7.16 8.39 9.23 9.67 10.78 10.65 10.55 9.88 9.99 9.77 9.11 9.46 9.92 9.78 9.88 10.17 9.72 9.66 9.54 8.82 8.75 9.75 10.92 12.10 11.71 10.19 8.62 8.50 9.27 8.76 8.96

7.93 6.54 7.31 6.47 7.46 6.10 9.01 7.18 9.63 8.06 10.25 8.44 11.49 9.46 10.41 9.33 10.25 9.11 9.48 8.54 11.03 8.92 10.56 8.57 10.25 8.09 10.87 8.36 10.56 8.71 9.94 8.41 9.17 8.51 11.03 9.03 11.18 8.85 9.79 8.46 9.48 8.32 9.63 7.69 10.41 8.00 11.49 9.04 12.42 10.14 12.57 11.18 12.27 10.68 9.94 9.04 8.54 7.42 9.48 7.76 10.09 8.52 9.01 7.83 10.72 8.08

185

6.82 6.03 6.82 7.44 8.67 9.29 10.69 9.14 9.29 8.52 10.38 10.07 9.92 10.38 9.92 9.29 8.21 9.92 10.38 8.67 8.37 8.52 10.23 11.31 12.40 12.09 11.16 8.52 7.44 8.67 9.14 7.90 10.07

5.45 5.40 5.37 5.99 7.08 7.41 8.43 8.31 8.07 7.57 8.05 7.67 7.29 7.49 7.72 7.42 7.56 8.11 8.08 7.39 7.34 6.70 7.19 8.22 9.27 10.15 9.50 7.77 6.35 6.84 7.61 6.85 7.23

6.44 5.04 6.13 6.75 7.52 7.98 9.37 7.52 8.44 7.37 9.21 8.91 8.91 9.06 8.60 7.68 7.22 9.83 9.83 6.91 7.83 8.14 9.83 10.61 11.22 11.22 9.06 7.83 6.75 8.29 8.91 7.68 8.91

4.79 4.71 4.80 5.44 6.07 6.41 7.29 7.30 6.90 6.60 7.03 6.78 6.69 6.67 6.86 6.59 6.86 7.31 7.26 6.43 6.35 6.12 6.68 7.50 8.34 9.11 8.26 6.75 5.73 6.35 7.01 6.24 6.62

4.07 3.91 6.26 5.95 4.54 4.69 5.17 4.69 5.17 5.01 5.32 5.79 5.63 5.79 5.79 5.17 5.17 5.63 5.63 5.17 5.48 5.32 5.48 5.63 5.95 6.11 5.63 5.79 5.63 5.95 5.79 5.63 6.11

3.70 3.75 5.03 4.53 4.10 4.18 4.42 4.48 4.49 4.57 4.69 4.82 4.72 4.81 4.97 4.82 5.10 5.16 5.04 5.09 5.20 5.11 5.15 5.34 5.56 5.84 5.61 5.68 5.55 5.75 5.64 5.53 5.74

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

04/08/03 04/09/03 04/10/03 04/11/03 04/12/03 04/13/03 04/14/03 04/15/03 04/16/03 04/17/03 04/18/03 04/19/03 04/20/03 04/21/03 04/22/03 04/23/03 04/24/03 04/25/03 04/26/03 04/27/03 04/28/03 04/29/03 04/30/03 05/01/03 05/02/03 05/03/03 05/04/03 05/05/03 05/06/03 05/07/03 05/08/03 05/09/03 05/10/03

13.67 15.56 16.35 16.51 15.87 14.76 12.28 12.90 14.13 14.29 13.36 14.13 15.40 14.76 16.03 16.98 16.03 14.29 14.13 14.13 14.29 13.98 12.90 15.56 17.46 16.51 15.40 13.98 15.40 15.24 14.92 15.87 16.51

11.35 13.09 14.39 15.19 14.89 13.05 11.59 11.31 12.51 12.90 11.90 11.65 13.10 13.99 14.11 14.86 13.83 12.51 12.70 12.13 12.67 12.25 12.17 12.58 14.81 15.50 13.84 12.72 13.27 13.79 13.36 14.12 14.53

12.90 14.13 14.92 15.39 13.52 11.51 10.58 11.66 12.28 12.90 11.66 12.43 13.67 12.59 13.98 14.76 12.59 13.82 12.28 13.06 12.43 13.36 12.28 14.60 15.55 13.98 12.28 12.59 13.82 13.67 13.52 13.36 14.76

10.75 11.73 12.53 13.21 12.34 10.48 9.64 9.60 10.80 11.07 10.21 9.97 11.36 11.69 11.77 12.10 11.24 10.93 10.80 10.73 10.68 10.85 10.77 11.26 12.94 12.88 11.27 10.82 11.48 11.98 11.61 12.05 12.07

11.06 11.52 11.98 12.14 10.91 9.82 9.04 10.44 10.44 10.28 9.82 10.75 11.21 10.75 9.82 10.91 9.97 9.66 9.66 10.28 9.82 10.44 9.51 11.83 11.83 10.91 9.97 10.44 11.21 11.36 11.06 10.44 11.67

9.20 9.87 10.27 10.60 9.63 8.53 8.18 8.21 8.81 8.80 8.21 8.33 9.09 9.23 8.73 9.14 8.52 8.54 8.43 8.36 8.45 8.84 8.20 9.24 9.70 9.47 8.93 8.88 9.24 9.57 9.33 9.09 9.55

10.87 11.18 11.64 11.80 10.09 8.86 8.39 10.25 10.09 9.94 9.79 10.56 11.03 10.09 9.17 10.56 9.17 9.63 9.17 10.09 9.63 9.94 8.54 11.49 11.64 9.94 9.63 10.25 11.03 11.03 11.03 9.63 11.33

186

8.63 9.28 9.59 9.84 8.86 7.97 7.61 7.83 8.27 8.19 7.78 7.92 8.58 8.51 8.06 8.58 8.00 8.14 7.91 8.00 8.05 8.38 7.74 8.87 9.18 8.92 8.50 8.46 8.83 9.08 8.93 8.60 9.14

10.69 10.85 11.16 11.16 9.61 8.67 7.90 9.92 9.61 9.45 9.45 10.23 10.69 9.14 8.52 10.23 8.83 9.61 8.67 9.61 9.45 9.45 8.21 11.01 11.31 9.29 8.98 9.92 10.69 10.54 10.54 8.98 10.69

8.06 8.57 8.81 9.06 8.12 7.45 7.07 7.40 7.71 7.55 7.31 7.47 8.12 7.87 7.46 8.04 7.54 7.71 7.42 7.61 7.63 7.84 7.30 8.36 8.61 8.31 8.01 8.02 8.38 8.52 8.43 8.10 8.69

9.83 9.52 10.30 9.99 8.44 8.29 7.06 8.91 8.76 8.60 8.60 9.21 10.14 7.83 7.83 9.21 8.44 8.91 7.83 8.91 8.76 8.91 7.68 9.83 10.30 8.60 8.60 9.37 9.99 9.83 9.68 8.44 9.83

7.32 7.61 7.90 7.93 7.20 6.81 6.48 6.80 6.94 6.83 6.70 6.86 7.46 7.09 6.83 7.32 7.02 7.19 6.88 7.19 7.17 7.29 6.86 7.75 7.94 7.64 7.44 7.58 7.82 7.92 7.89 7.62 8.14

6.42 6.42 6.73 6.26 6.26 6.42 6.26 6.11 6.11 6.11 6.11 6.26 7.19 6.57 6.42 6.57 7.04 6.88 6.57 7.04 7.19 6.88 6.73 7.19 7.35 7.19 7.19 7.19 7.50 7.50 7.50 7.35 7.66

6.13 6.16 6.36 6.14 6.06 5.99 6.00 5.85 5.97 5.91 5.90 6.06 6.55 6.32 6.25 6.28 6.64 6.61 6.45 6.73 6.79 6.70 6.66 6.84 7.01 6.94 7.03 7.05 7.17 7.25 7.28 7.31 7.38

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

05/11/03 05/12/03 05/13/03 05/14/03 05/15/03 05/16/03 05/17/03 05/18/03 05/19/03 05/20/03 05/21/03 05/22/03 05/23/03 05/24/03 05/25/03 05/26/03 05/27/03 05/28/03 05/29/03 05/30/03 05/31/03 06/01/03 06/02/03 06/03/03 06/04/03 06/05/03 06/06/03 06/07/03 06/08/03 06/09/03 06/10/03 06/11/03 06/12/03

16.98 16.35 17.46 18.75 19.24 18.11 16.67 15.08 15.72 17.30 18.59 20.21 22.52 22.36 21.03 21.36 23.03 23.88 24.40 23.71 20.70 21.03 20.70 20.86 20.70 21.52 22.69 22.36 23.54 23.71 23.37 22.02 21.69

15.34 15.28 15.06 16.48 17.38 16.31 14.70 13.26 13.40 14.59 16.57 17.68 19.63 20.74 19.25 19.13 20.30 21.42 22.30 20.97 19.29 19.07 19.15 18.83 18.84 19.19 20.31 20.52 21.05 21.56 21.40 20.32 19.68

14.76 13.52 16.18 17.29 17.77 16.81 14.76 14.13 14.92 16.02 16.49 18.57 19.71 20.19 16.97 18.89 20.19 20.51 21.33 19.06 17.61 18.73 18.73 18.89 19.22 19.71 20.03 20.19 20.68 20.68 20.51 16.97 17.13

13.10 12.68 12.92 14.41 15.25 14.26 12.82 11.87 12.20 13.29 14.41 15.34 16.67 17.28 16.09 16.17 17.14 17.75 18.58 17.27 15.93 16.22 16.54 16.48 16.52 16.79 17.37 17.60 17.86 18.12 17.81 15.64 15.49

11.52 10.75 12.92 13.53 13.53 12.45 11.98 11.83 12.61 12.92 12.76 13.99 14.62 14.31 12.92 14.15 14.78 15.41 14.93 13.69 13.99 14.46 14.78 14.78 14.78 15.09 15.57 15.41 15.89 15.89 14.62 14.78 15.26

9.98 9.71 10.35 11.02 11.41 10.61 9.95 9.58 9.96 10.50 11.03 11.45 12.06 12.17 11.39 11.82 12.31 12.75 12.84 12.33 12.23 12.21 12.41 12.45 12.55 12.76 13.08 13.19 13.33 13.51 12.96 12.46 12.74

11.03 10.41 12.57 13.19 13.04 12.11 11.64 11.49 12.27 12.73 12.42 13.35 14.12 13.81 11.80 13.51 14.12 14.75 14.12 13.04 13.35

9.45 9.20 9.88 10.43 10.71 9.99 9.46 9.19 9.59 10.02 10.41 10.81 11.31 11.35 10.60 11.13 11.49 11.90 11.86 11.49 11.44

14.28 14.59 14.91 14.75 15.22 15.22 13.97 14.28 14.91

13.59 12.00 12.28 12.34 12.51 12.65 12.15 11.95 12.26

187

10.54 9.92 11.93 12.71 12.40 11.62 11.31 11.01 11.78 12.24 11.93 12.71 13.33 13.18 11.16 12.87 13.49 13.79 13.33 12.24 13.02 13.18 13.49 13.64 13.64 13.95 14.26 14.11 14.42 14.42 13.49 13.79 14.26

8.86 8.65 9.28 9.73 9.91 9.34 8.97 8.75 9.15 9.47 9.74 10.10 10.49 10.51 9.86 10.38 10.68 11.06 10.91 10.75 10.71 10.72 10.93 11.00 11.07 11.27 11.53 11.60 11.76 11.88 11.48 11.49 11.76

9.68 9.21 10.92 11.22 11.07 10.46 10.30 9.99 10.76 11.07 10.92 11.53 11.84 11.84 10.14 11.53 12.00 12.31 12.16 11.07 12.00 12.00 12.31 12.47 12.47 12.62 12.93 12.93 13.08 13.08 12.47 12.78 13.08

8.19 8.05 8.57 8.86 8.98 8.55 8.38 8.28 8.58 8.81 8.96 9.25 9.50 9.52 9.09 9.50 9.72 10.05 9.90 9.81 9.82 9.90 10.08 10.17 10.26 10.42 10.64 10.72 10.87 11.00 10.73 10.86 11.10

7.66 7.66 7.81 7.97 7.97 7.97 7.97 8.12 7.97 8.12 8.28 8.28 8.28 8.43 8.28 8.58 8.74 8.89 8.89 9.05 9.05 9.05 9.21 9.36 9.52 9.67 9.83 9.83 9.83 10.14 10.14 10.45 10.45

7.42 7.43 7.52 7.65 7.71 7.67 7.78 7.85 7.87 7.98 7.96 8.07 8.13 8.19 8.21 8.26 8.41 8.53 8.56 8.64 8.82 8.85 8.98 9.12 9.23 9.31 9.49 9.56 9.69 9.82 9.96 10.14 10.26

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

06/13/03 06/14/03 06/15/03 06/16/03 06/17/03 06/18/03 06/19/03 06/20/03 06/21/03 06/22/03 06/23/03 06/24/03 06/25/03 06/26/03 06/27/03 06/28/03 06/29/03 06/30/03 07/01/03 07/02/03 07/03/03 07/04/03 07/05/03 07/06/03 07/07/03 07/08/03 07/09/03 07/10/03 07/11/03 07/12/03 07/13/03 07/14/03 07/15/03

22.52 22.86 22.36 23.20 24.23 23.20 21.19 20.37 19.89 19.57 19.40 19.57 20.70 21.86 22.86 23.37 23.71 23.88 23.71 22.86 23.20 23.37 23.37 23.37 23.88 23.71 24.06 24.40 25.09 25.44 24.74 24.06 24.40

20.40 20.82 20.69 20.92 21.73 21.23 19.87 19.22 18.28 17.93 17.73 17.81 18.61 19.77 20.72 21.43 21.79 21.83 21.82 21.12 21.14 21.36 21.53 21.59 21.91 21.95 22.04 22.26 23.02 23.45 23.16 22.41 22.45

18.25 18.57 18.25 19.22 19.54 18.09 17.13 17.29 17.13 16.97 16.97 16.81 17.93 18.57 19.06 19.54 19.71 19.71 19.54 19.22 19.38 19.54 19.54 19.71 19.87 19.87 19.87 20.19 20.51 20.68 20.51 20.19 20.51

16.69 16.72 16.67 17.15 17.56 17.08 16.37 16.01 15.40 15.43 15.30 15.46 16.07 16.75 17.35 17.88 18.10 18.40 18.04 17.67 17.67 17.90 17.91 18.03 18.29 18.46 18.28 18.55 19.00 19.13 19.14 18.80 18.91

14.93 15.57 15.57 16.21 16.36 15.57 14.62 14.93 15.26 15.26 15.26 15.41 16.04 16.36 16.83 16.99 17.15 17.15 16.99 16.83 17.15 17.15 17.15 17.31 17.63 17.47 17.79 17.96 18.12 18.28 18.12 18.12 18.28

13.13 13.26 13.22 13.67 13.88 13.75 13.29 13.28 13.06 13.10 13.02 13.27 13.69 14.05 14.38 14.61 14.75 14.90 14.73 14.57 14.71 14.81 14.84 14.96 15.22 15.30 15.36 15.53 15.75 15.86 15.87 15.77 15.94

14.59 15.22 15.07 15.70 15.86 15.22 14.28 14.59 14.91 14.91 14.91 15.22 15.86 16.02 16.49 16.65 16.81 16.65 16.49 16.49 16.65 16.81 16.81 16.97 17.13 16.97 17.44 17.44 17.76 17.76 17.61 17.61 17.76

188

12.61 12.75 12.70 13.14 13.28 13.20 12.82 12.91 12.73 12.78 12.70 12.96 13.36 13.65 13.95 14.16 14.29 14.39 14.22 14.11 14.27 14.40 14.41 14.53 14.71 14.80 14.88 15.01 15.21 15.29 15.28 15.24 15.37

14.11 14.57 14.42 15.05 15.21 14.89 13.79 14.26 14.57 14.57 14.57 14.73 15.37 15.53 15.84 16.00 16.16 16.00 16.00 16.00 16.16 16.32 16.32 16.48 16.63 16.48 16.79 16.95 17.11 17.11 17.11 17.11 17.27

12.02 12.18 12.16 12.52 12.67 12.61 12.34 12.46 12.39 12.42 12.34 12.60 12.96 13.17 13.42 13.61 13.72 13.80 13.69 13.65 13.78 13.91 13.93 14.05 14.20 14.28 14.36 14.50 14.65 14.73 14.74 14.73 14.84

13.08 13.39 13.39 13.85 14.01 13.85 13.39 13.54 13.70 13.70 13.54 13.85 14.32 14.47 14.63 14.78 14.94 14.78 14.94 14.94 14.94 15.10 15.26 15.42 15.42 15.42 15.73 15.89 16.05 16.05 15.89 16.05 16.05

11.29 11.45 11.49 11.78 11.91 11.92 11.75 11.87 11.90 11.91 11.84 12.13 12.38 12.53 12.75 12.88 12.98 13.03 12.98 12.99 13.11 13.24 13.28 13.40 13.50 13.57 13.67 13.79 13.91 14.01 14.02 14.04 14.16

10.61 10.53 10.69 10.84 11.00 11.16 11.16 11.16 11.31 11.31 11.46 11.62 11.62 11.77 11.93 11.93 12.08 12.08 12.08 12.23 12.23 12.39 12.54 12.54 12.54 12.70 12.86 12.86 13.01 13.01 13.01 13.16 13.32

10.33 10.40 10.52 10.63 10.79 10.88 10.95 11.07 11.18 11.23 11.30 11.41 11.48 11.58 11.73 11.78 11.86 11.96 11.99 12.09 12.16 12.23 12.31 12.39 12.46 12.54 12.67 12.70 12.80 12.92 12.94 13.01 13.11

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

07/16/03 07/17/03 07/18/03 07/19/03 07/20/03 07/21/03 07/22/03 07/23/03 07/24/03 07/25/03 07/26/03 07/27/03 07/28/03 07/29/03 07/30/03 07/31/03 08/01/03 08/02/03 08/03/03 08/04/03 08/05/03 08/06/03 08/07/03 08/08/03 08/09/03 08/10/03 08/11/03 08/12/03 08/13/03 08/14/03 08/15/03 08/16/03 08/17/03

25.09 25.27 25.09 25.62 25.62 25.62 26.14 25.44 24.74 23.71 23.37 23.71 24.74 25.27 25.44 25.44 24.74 23.88 21.69 23.54 24.23 24.06 23.71 23.37 23.37 23.71 23.37 22.69 23.37 22.86 23.37 23.37 22.69

23.15 23.38 23.56 24.06 24.05 23.73 24.22 24.33 23.52 22.70 22.34 22.13 22.95 23.56 23.83 23.68 23.26 22.24 21.05 21.59 22.48 22.61 22.32 21.90 21.69 21.85 21.92 21.30 21.54 21.49 21.63 21.90 21.18

20.68 20.35 20.84 21.01 21.33 21.17 21.83 21.17 20.35 20.35 20.03 20.68 21.01 21.67 21.83 21.50 21.01 20.35 19.87 21.33 21.67 21.50 21.17 21.01 21.33 21.33 21.33 21.01 21.01 21.17 21.67 21.50 21.01

19.21 19.11 19.22 19.78 19.94 19.86 20.04 20.02 19.34 18.94 18.88 18.92 19.66 20.23 20.44 20.22 19.84 19.21 18.75 19.60 20.27 20.17 19.96 19.68 19.79 19.99 20.08 19.88 19.88 19.97 20.40 20.46 19.76

18.44 17.79 18.60 18.76 18.93 18.93 18.93 18.93 17.63 18.12 17.79 18.93 19.74 19.90 19.90 19.74 19.68 18.55 18.71 20.00 20.16 20.16 20.16 20.16 20.48 20.64 20.64 20.32 20.64 20.81 20.32 20.48 20.64

16.15 15.90 16.29 16.52 16.70 16.69 16.75 16.81 16.26 16.73 16.35 16.84 17.30 17.58 17.62 17.60 17.48 17.01 17.28 17.86 18.18 18.13 18.17 18.11 18.34 18.50 18.69 18.53 18.74 18.76 18.82 19.03 18.72

17.92 17.28 18.08 18.24 18.41 18.41 18.41 18.24 16.81 17.76 17.28 18.57 19.06 19.22 19.22 19.22 19.06 17.28 17.92 19.55 19.71 19.71 19.71 19.71 20.19 20.19 20.36 20.03 20.36 20.52 20.03 20.19 20.36

189

15.55 15.29 15.69 15.90 16.07 16.03 16.10 16.15 15.63 16.14 15.81 16.29 16.66 16.91 16.96 16.98 16.89 16.36 16.76 17.31 17.57 17.55 17.59 17.57 17.81 17.97 18.17 18.10 18.29 18.33 18.34 18.61 18.34

17.43 16.79 17.43 17.59 17.91 17.91 17.91 17.75 16.32 17.27 17.11 18.07 18.56 18.88 18.72 18.72 18.72 16.95 17.75 19.21 19.37 19.37 19.37 19.54 19.86 20.03 20.03 19.86 20.19 20.19 19.70 20.03 20.19

15.01 14.79 15.16 15.33 15.51 15.48 15.54 15.61 15.18 15.65 15.42 15.88 16.21 16.44 16.47 16.52 16.51 16.03 16.47 16.96 17.18 17.20 17.27 17.29 17.55 17.71 17.87 17.87 18.05 18.12 18.10 18.40 18.22

16.21 15.73 16.53 16.53 16.68 16.68 16.84 16.68 15.42 16.53 16.37 17.16

14.28 14.13 14.47 14.60 14.78 14.73 14.83 14.89 14.62 15.00 14.88 14.99

17.64 17.80 17.80 17.80 16.37 17.16 18.28 18.44 18.61 18.61 18.61 19.09 19.09 19.25 19.09 19.41 19.41 18.93 19.41 19.57

16.37 15.77 15.85 15.88 15.55 15.98 16.38 16.54 16.64 16.71 16.79 17.02 17.18 17.34 17.46 17.56 17.66 17.67 17.93 17.83

13.32 13.32 13.47 13.63 13.63 13.78 13.93 13.93 14.09 14.24 14.24 14.56 14.56 14.71 14.87 15.03 15.19 15.34 15.34 15.66 15.82 15.98 16.13 16.29 16.45 16.61 16.77 16.93 17.08 17.24 17.24 17.41 17.57

13.18 13.27 13.38 13.45 13.54 13.61 13.73 13.78 13.92 14.08 14.13 14.28 14.50 14.64 14.74 14.89 15.03 15.16 15.31 15.50 15.65 15.84 15.94 16.17 16.33 16.52 16.69 16.86 17.01 17.13 17.21 17.33 17.40

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

08/18/03 08/19/03 08/20/03 08/21/03 08/22/03 08/23/03 08/24/03 08/25/03 08/26/03 08/27/03 08/28/03 08/29/03 08/30/03 08/31/03 09/01/03 09/02/03 09/03/03 09/04/03 09/05/03 09/06/03 09/07/03 09/08/03 09/09/03 09/10/03 09/11/03 09/12/03 09/13/03 09/14/03 09/15/03 09/16/03 09/17/03 09/18/03 09/19/03

22.86 23.37 23.03 22.02 20.86 21.86 22.52 22.69 21.86 22.36 22.02 21.36 21.86 21.52 20.86 22.02 22.36 21.52 22.52 23.20 22.19 20.70 17.94 16.98 18.43 18.59 17.78 17.46 16.82 16.82 16.51 16.19 16.67

21.18 21.65 21.62 20.35 20.13 20.20 20.93 21.28 20.48 20.48 20.82 20.28 20.04 20.05 19.68 20.20 20.66 20.56 20.95 21.30 20.84 18.97 16.45 15.76 16.76 17.65 16.43 16.08 15.93 16.00 15.50 14.95 15.17

21.50 21.83 21.50 20.35 20.51 21.17 21.67 21.67 20.84 22.00 22.00 21.50 22.00 21.67 21.17 22.16 22.83 21.83 22.83 22.83 21.33 19.71 17.77 17.77 19.38 19.38 18.25 18.57 17.61 17.93 17.29 16.97 17.61

20.08 20.48 20.47 19.21 19.30 19.65 20.28 20.39 19.82 20.10 20.50 19.79 19.82 19.79 19.60 20.16 20.70 20.50 20.85 20.92 20.20 18.69 16.61 16.26 17.52 18.16 16.55 16.59 16.60 16.67 16.06 15.34 15.80

20.97 21.30 20.81 19.68 20.00 21.14 21.30 21.47 20.48 21.63 20.97 20.16 21.14 20.97 20.64 21.47 21.30 20.97 20.97 21.14 20.32 19.52 18.07 19.03 20.00 19.52 19.03 19.19 18.55 18.39 17.74 17.91 18.39

19.10 19.35 19.26 18.38 18.99 19.18 19.40 19.47 18.97 19.61 19.55 18.96 19.33 19.26 19.20 19.60 19.76 19.67 19.63 19.66 19.18 18.32 17.12 17.49 18.17 18.31 17.15 17.56 17.32 17.42 16.65 16.35 16.85

20.68 21.01 20.52 18.89 19.87 20.84 21.01 21.17 19.55 21.33 20.84 19.71 21.01 20.84 20.36 21.17 21.17 20.68 20.68 20.84 19.87 18.89 17.61 19.22 19.87 19.06 19.06 19.22 18.08 18.41 17.76 17.92 18.41

190

18.71 18.95 18.83 18.01 18.69 18.86 19.01 19.08 18.54 19.26 19.08 18.53 18.97 18.88 18.79 19.20 19.30 19.17 19.15 19.15 18.70 17.94 16.91 17.43 18.03 18.00 17.09 17.41 17.08 17.24 16.53 16.28 16.72

20.51 20.84 20.51 18.88 20.03 20.84 20.84 21.00 19.21 21.33 20.67 19.70 20.84 20.84 20.35 21.17 21.00 20.51 20.51 20.67 19.70 18.88 17.59 19.37 20.03 18.88 19.37 19.54 18.23 18.39 18.07 18.23 18.56

18.53 18.73 18.63 17.95 18.58 18.73 18.83 18.89 18.34 19.09 18.87 18.38 18.82 18.72 18.64 19.02 19.04 18.88 18.85 18.87 18.48 17.82 16.99 17.51 18.07 17.90 17.24 17.47 17.08 17.25 16.60 16.41 16.74

19.89 20.06 19.73 18.61 19.73 20.06 20.06 20.22 18.93 20.38 20.06 19.41 20.22 20.22 19.73 20.38 20.22 19.73 19.73 20.06 19.25 18.77 17.64 18.93 19.73 18.77 19.25 19.25 18.12 18.28 18.12 18.28 18.28

18.08 18.23 18.15 17.70 18.17 18.33 18.37 18.42 17.96 18.62 18.42 18.07 18.40 18.33 18.27 18.56 18.51 18.36 18.33 18.36 18.06 17.60 17.09 17.51 17.95 17.63 17.34 17.38 17.00 17.15 16.62 16.50 16.64

17.73 17.73 17.73 17.73 17.89 17.89 17.89 18.05 17.89 18.05 18.05 18.05 18.05 18.05 18.05 18.05 18.05 17.89 17.89 17.89 17.73 17.73 17.89 17.89 17.89 17.73 17.73 17.73 17.41 17.41 17.08 17.08 16.93

17.49 17.59 17.61 17.64 17.74 17.77 17.78 17.81 17.78 17.85 17.85 17.88 17.89 17.93 17.94 17.93 17.81 17.77 17.71 17.73 17.72 17.72 17.75 17.77 17.79 17.67 17.59 17.50 17.36 17.21 16.99 16.84 16.69

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

09/20/03 09/21/03 09/22/03 09/23/03 09/24/03 09/25/03 09/26/03 09/27/03 09/28/03 09/29/03 09/30/03 10/01/03 10/02/03 10/03/03 10/04/03 10/05/03 10/06/03 10/07/03 10/08/03 10/09/03 10/10/03 10/11/03 10/12/03 10/13/03 10/14/03 10/15/03 10/16/03 10/17/03 10/18/03 10/19/03 10/20/03 10/21/03 10/22/03

17.30 17.14 17.46 17.62 17.62 17.62 18.43 18.92 18.75 18.43 18.43 17.78 18.92 19.02 18.69 18.53 18.53 18.04 17.72 16.92 15.02 13.62 13.92 13.92 13.92 13.00 13.92 14.86 14.70 14.86 15.18 15.65 15.02

15.83 15.92 16.00 16.25 16.27 16.26 16.97 17.60 17.47 17.34 17.28 16.96 17.66 17.92 17.62 17.52 17.51 17.20 16.59 15.74 13.95 12.53 12.86 12.88 13.07 12.16 12.71 13.74 14.03 14.04 14.40 14.68 14.22

18.09 17.93 18.41 18.57 18.25 18.25 18.89 19.06 19.06 18.73 18.73 18.41 18.89 19.22 18.73 18.73 18.73 18.09 18.09 16.65 15.07 13.36 14.76 14.29 14.76 13.21 14.60 15.39 15.55 15.87 15.87 16.02 15.55

16.33 16.21 16.35 16.61 16.41 16.45 16.89 17.39 17.37 17.27 17.19 17.03 17.74 17.80 17.40 17.32 17.30 17.05 16.61 15.90 14.06 12.74 13.63 13.26 13.41 12.50 13.27 14.09 14.30 14.55 14.67 14.68 14.28

18.07 18.07 18.39 18.23 18.23 17.91 18.39 18.39 18.39 18.23 18.23 18.16 18.64 18.48 18.32 18.16 18.16 17.83 17.67 17.19 15.62 14.82 15.46 14.98 14.98 14.51 15.77 16.09 16.56 16.41 16.24 16.09 15.77

16.90 16.69 16.76 16.83 16.69 16.71 16.93 17.11 17.08 17.03 17.01 17.01 17.54 17.33 17.14 17.18 17.13 16.89 16.70 16.04 14.54 14.03 14.79 14.19 14.29 13.49 14.46 14.95 15.20 15.28 15.15 15.08 14.79

18.08 17.92 18.24 18.08 18.08 17.92 18.24 18.24 18.24 17.92 17.92 17.76 18.41 18.08 18.08 17.92 17.92 17.28 17.28 16.65 15.22 14.59 15.38 14.91 14.59 14.28 15.22 15.54 15.86 15.70 15.38 15.38 14.91

191

16.67 16.45 16.50 16.51 16.41 16.37 16.58 16.72 16.69 16.61 16.63 16.53 17.07 16.81 16.66 16.70 16.64 16.39 16.25 15.62 14.21 13.75 14.53 13.93 13.98 13.12 13.94 14.31 14.54 14.44 14.21 14.10 13.78

18.39 18.23 18.23 18.23 18.23 17.91 18.23 18.23 18.07 17.91 17.91 17.43 18.23 17.91 18.07 17.91 17.91 17.11 17.43 16.63 15.21 14.73 15.37 15.05 14.89 14.11 14.89 15.21 15.53 15.05 14.89 14.89 14.42

16.65 16.43 16.40 16.36 16.30 16.21 16.39 16.44 16.42 16.36 16.36 16.26 16.79 16.52 16.43 16.49 16.43 16.15 16.11 15.48 14.15 13.77 14.54 13.98 13.96 12.95 13.53 13.84 14.11 13.88 13.59 13.47 13.15

18.12 17.96 17.96 17.80 17.80 17.64 17.80 17.80 17.64 17.48 17.48 18.28 17.96 17.48 17.64 17.64 17.64 16.84 17.16 16.21 15.42 14.94 15.42 15.42 15.10 13.39 14.47 14.78 14.78 14.32 14.16 14.32 13.85

16.49 16.27 16.19 16.12 16.07 15.94 16.05 16.06 16.04 16.00 15.98 15.98 16.31 16.14 16.10 16.11 16.14 15.84 15.88 15.23 14.24 13.90 14.59 14.15 13.92 12.85 13.32 13.40 13.66 13.29 13.00 12.93 12.69

16.61 16.45 16.29 16.13 16.13 15.98 15.82 15.82 15.82 15.82 15.82 15.82 15.66 15.91 16.23 16.07 16.07 15.91 15.91

16.41 16.19 16.02 15.97 15.89 15.77 15.66 15.60 15.62 15.62 15.59 15.67 15.55 15.69 15.84 15.85 15.82 15.83 15.63

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

10/23/03 10/24/03 10/25/03 10/26/03 10/27/03 10/28/03 10/29/03 10/30/03 10/31/03 11/01/03 11/02/03 11/03/03 11/04/03 11/05/03 11/06/03 11/07/03 11/08/03 11/09/03 11/10/03 11/11/03 11/12/03 11/13/03 11/14/03 11/15/03 11/16/03 11/17/03 11/18/03 11/19/03 11/20/03 11/21/03 11/22/03 11/23/03 11/24/03

14.39 13.00 11.91 12.53 13.00 14.23 13.92 11.44 9.27 8.34 7.42 8.34 8.04 7.57 7.11 6.96 8.66 8.50 9.89 11.14 10.21 8.81 7.88 8.96 9.89 9.58 10.36 10.36 9.74 8.34 6.80 5.71 6.02

13.71 12.12 11.19 11.41 12.04 13.14 12.81 10.17 8.74 7.63 6.95 7.81 7.54 6.98 6.38 6.26 7.61 8.01 9.05 10.30 9.48 8.09 7.37 8.23 9.46 9.24 9.55 9.74 9.01 7.54 5.65 4.92 5.35

14.29 12.59 11.66 12.28 13.06 13.82 13.36 10.74 9.18 7.80 7.18 8.11 7.96 7.03 6.87 6.72 8.11 8.11 9.49 10.27 8.88 7.18 7.03 8.26 9.34 8.88 9.80 9.80 9.03 7.18 5.48 5.01 5.48

13.57 11.63 10.63 10.97 11.81 12.89 12.45 9.74 8.22 6.84 6.44 7.38 7.02 6.28 5.78 5.80 7.02 7.44 8.49 9.37 8.11 6.67 6.18 7.31 8.65 8.43 8.74 9.04 8.22 6.43 4.45 3.90 4.47

15.30 13.43 12.81 13.74 14.67 14.67 14.67 11.88 10.49 9.87 10.03 10.03 9.49 9.03 8.57 9.33 9.96 9.96 10.58 10.88 9.96 9.03 8.57 10.11 10.42 9.96 10.42 10.58 10.27 8.57 7.19 6.88 7.34

14.15 12.33 11.75 12.32 13.32 13.94 13.16 10.80 9.81 8.97 8.88 9.17 9.19 8.38 7.74 8.07 8.87 9.30 9.84 10.32 8.69 8.10 7.56 8.96 9.73 9.39 9.51 9.93 9.00 7.57 5.96 5.75 6.40

14.12 12.27 11.96 13.04 13.81 13.81 13.51 10.56 9.63 9.01 8.86 9.18 9.03 8.26 7.94 8.10 9.18 9.03 9.34 9.81 8.72 7.79 7.32 8.56 9.03 8.56 9.03 9.18 8.87 7.48 6.23 5.61 6.07

192

13.16 11.30 10.78 11.50 12.43 12.95 12.18 9.65 8.67 7.83 7.70 8.39 8.20 7.38 6.88 6.94 7.80 8.19 8.51 9.08 7.56 6.97 6.47 7.58 8.33 8.13 8.12 8.57 7.89 6.56 5.00 4.49 5.21

13.18 11.62 11.47 12.71 13.33 13.33 12.56 9.76 8.83 8.21 7.90 8.52 8.06 7.44 7.13 7.44 8.52 7.90 8.37 8.83 7.28 6.51 6.19 7.28 7.90 7.28 8.06 8.06 7.59 6.03 4.63 4.47 5.26

12.55 10.75 10.35 11.13 12.01 12.44 11.57 9.03 8.03 7.28 7.09 7.78 7.44 6.51 5.95 6.11 7.06 7.23 7.58 8.06 6.53 5.76 5.37 6.55 7.25 6.98 7.08 7.49 6.78 5.34 3.68 3.39 4.30

13.08 11.84 11.84 12.62 13.08 12.93 12.47 9.83 9.52 9.06 8.29 9.06 9.06 7.52 7.68 7.68 8.60 7.68 8.29 7.98 7.37 6.59 6.44 7.06 7.68 6.91 7.83 7.37 7.52 6.28 4.57 4.88 5.51

12.19 10.75 10.53 11.31 11.92 12.26 11.27 9.11 8.36 7.76 7.55 8.39 7.69 6.77 6.24 6.49 7.29 7.14 7.39 7.53 6.35 5.61 5.49 6.42 6.86 6.59 6.77 7.03 6.60 5.31 3.89 3.83 4.65

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

11/25/03 11/26/03 11/27/03 11/28/03 11/29/03 11/30/03 12/01/03 12/02/03 12/03/03 12/04/03 12/05/03 12/06/03 12/07/03 12/08/03 12/09/03 12/10/03 12/11/03 12/12/03 12/13/03 12/14/03 12/15/03 12/16/03 12/17/03 12/18/03 12/19/03 12/20/03 12/21/03 12/22/03 12/23/03 12/24/03 12/25/03 12/26/03 12/27/03

5.71 6.80 6.49 6.33 7.73 8.81 9.89 10.21 10.36 9.58 7.88 9.27 9.27 8.50 7.73 6.80 7.88 7.27 7.73 7.88 7.11 6.18 6.64 6.33 5.71 6.49 7.57 6.96 6.33 6.02 7.11 6.80 4.77

5.35 5.94 5.92 5.89 7.01 8.32 9.26 9.66 9.85 8.47 7.67 8.56 9.08 8.03 7.00 6.50 7.30 6.83 7.26 7.69 6.56 5.75 6.03 5.83 5.32 5.91 6.88 6.48 5.78 5.66 6.53 5.68 4.40

5.01 6.10 5.63 6.10 7.03 7.96 8.88 12.28 13.52 8.72 10.27 10.58 12.59 7.49 6.87 6.10 6.72 5.94 6.87 7.18 6.25 5.01 5.94 5.32 5.01 5.63 6.87 6.10 4.86 5.63 6.56 5.48 3.76

4.55 5.30 4.91 5.31 6.53 7.53 8.18 8.55 8.20 5.64 8.00 8.72 6.21 5.72 6.02 5.78 6.15 5.63 6.42 6.72 5.61 4.48 5.08 4.56 4.36 4.99 5.88 5.43 4.52 5.15 5.87 4.41 3.21

7.19 7.65 7.65 7.81 8.72 9.33 9.64 9.96 9.96 9.64 9.49 9.80 9.64 8.57 8.27 7.50 7.81 7.50 8.11 8.11 7.34 6.57 6.57 6.57 6.73 7.34 7.96 7.34 6.73 7.03 7.34 6.57 5.18

6.50 7.15 6.69 6.90 7.80 8.62 9.01 9.25 9.29 8.31 8.71 9.39 8.88 8.05 7.10 6.82 7.29 6.89 7.39 7.63 6.62 5.81 6.21 6.01 5.94 6.47 7.16 6.31 5.88 6.53 6.68 5.48 4.36

6.07 6.54 6.39 6.54 7.32 8.10 8.54 8.86 8.86 8.24 8.39 8.70 8.39 7.46 6.69 6.07 6.69 6.22 6.84 6.69 5.91 5.29 5.60 5.44 5.44 6.07 6.53 5.76 5.13 5.76 6.22 5.29 3.88

193

5.40 5.97 5.68 5.74 6.62 7.44 7.85 7.99 8.04 7.08 7.58 8.22 7.67 6.72 5.67 5.39 5.99 5.63 6.17 6.40 5.23 4.51 4.81 4.64 4.56 5.18 5.85 4.95 4.44 5.24 5.49 4.19 2.97

5.10 5.72 5.41 5.41 6.35 6.97 7.44 7.74 7.90 7.13 7.44 7.59 7.28 6.19 5.57 4.94 5.72 5.10 5.88 5.72 4.79 4.01 4.63 4.47 4.47 5.10 5.57 4.79 4.16 4.79 5.26 4.32 2.90

4.44 4.98 4.70 4.73 5.75 6.54 6.81 7.03 7.11 6.17 6.67 7.32 6.74 5.73 4.63 4.37 5.09 4.66 5.25 5.46 4.26 3.56 3.82 3.74 3.64 4.31 4.97 4.00 3.50 4.35 4.68 3.26 2.10

5.35 5.97 5.66 5.51

4.74 5.16 4.79 4.54

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

12/28/03 12/29/03 12/30/03 12/31/03 01/01/04 01/02/04 01/03/04 01/04/04 01/05/04 01/06/04 01/07/04 01/08/04 01/09/04 01/10/04 01/11/04 01/12/04 01/13/04 01/14/04 01/15/04 01/16/04 01/17/04 01/18/04 01/19/04 01/20/04 01/21/04 01/22/04 01/23/04 01/24/04 01/25/04 01/26/04 01/27/04 01/28/04 01/29/04

5.24 5.24 4.77 4.46 4.93 5.08 4.93 5.24 3.99 2.09 2.73 4.62 5.39 5.39 5.08 5.08 4.93 4.77 4.30 4.30 5.08 5.08 5.55 5.86 5.86 5.55 4.93 4.77 4.77 5.39 5.71 6.49 6.96

4.87 4.86 4.21 3.99 4.30 4.68 4.55 4.61 2.60 1.60 1.97 3.54 4.94 4.96 4.69 4.96 4.76 4.55 4.05 3.88 4.54 4.78 4.97 5.48 5.67 5.35 4.38 4.16 3.92 4.55 5.26 6.02 6.47

3.92 4.23 3.92 3.92 4.38 4.70 4.38 4.54 2.82 1.40 2.03 4.07 4.86 4.70 4.54 4.23 4.23 3.76 2.82 3.13 3.76 3.60 4.38 4.07 3.92 4.07 3.29 3.60 3.60 4.54 4.86 5.17 5.48

3.39 3.79 3.31 3.27 3.59 4.14 3.84 3.70 1.34 0.76 1.57 2.94 3.97 4.07 3.96 3.72 3.65 3.32 2.50 2.43 3.18 2.97 3.48 3.76 3.70 3.52 2.71 2.76 2.45 3.50 4.21 4.67 5.02

5.64 5.96 5.80 5.49 6.26 6.11 5.80 5.64 4.71 3.62 3.93 5.33 5.80 5.96 5.64 5.33 5.18 4.71 4.24 4.09 4.87 4.56 5.02 5.02 4.71 4.87 4.40 4.40 4.87 5.49 5.49 5.49 5.80

4.75 5.15 4.77 4.78 5.16 5.48 4.96 4.85 2.87 2.65 3.19 4.38 5.03 5.10 4.91 4.62 4.53 4.00 3.52 3.49 4.12 3.89 4.29 4.45 4.40 4.21 3.55 3.54 3.63 4.46 4.85 5.12 5.29

4.35 4.51 4.51 4.19 4.98 4.98 4.51 4.35 3.25 2.14 2.62 4.19 4.67 4.82 4.51 4.19 4.04 3.41 2.93 2.77 3.57 3.41 3.72 3.57 3.57 3.57 2.93 2.93 3.57 4.19 4.19 4.35 4.67

194

3.47 3.88 3.63 3.58 4.13 4.25 3.72 3.63 1.73 1.45 1.94 3.27 3.90 3.94 3.69 3.47 3.32 2.88 2.24 2.24 2.89 2.68 2.98 3.24 3.22 3.05 2.35 2.26 2.41 3.22 3.61 3.93 4.09

3.22 3.53 3.53 3.22 4.16 3.84 3.53 3.37 2.27 1.31 1.79 3.37 3.84 3.84 3.37 3.06 2.90 2.42 1.63 1.63 2.58 2.27 2.58 2.58 2.42 2.58 2.11 1.79 2.58 3.22 3.22 3.37 3.69

2.64 2.98 2.84 2.66 3.37 3.34 2.87 2.76 0.95 0.61 1.15 2.50 3.04 3.07 2.81 2.52 2.36 1.94 1.31 1.29 2.01 1.75 2.01 2.30 2.28 2.07 1.40 1.38 1.54 2.31 2.67 3.00 3.20

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

01/30/04 01/31/04 02/01/04 02/02/04 02/03/04 02/04/04 02/05/04 02/06/04 02/07/04 02/08/04 02/09/04 02/10/04 02/11/04 02/12/04 02/13/04 02/14/04 02/15/04 02/16/04 02/17/04 02/18/04 02/19/04 02/20/04 02/21/04 02/22/04 02/23/04 02/24/04 02/25/04 02/26/04 02/27/04 02/28/04 02/29/04 03/01/04 03/02/04

7.57 6.33 5.71 5.55 5.39 7.11 7.11 6.02 6.02 6.64 6.80 6.18 5.39 5.08 5.08 5.55 6.33 5.55 6.64 8.19 8.50 7.88 7.27 6.49 6.80 6.49 5.39 6.49 7.57 7.42 6.96 6.18 7.27

6.78 5.71 5.45 5.08 4.58 6.10 6.39 5.64 5.36 5.76 5.86 5.53 5.09 4.91 4.38 4.41 5.24 5.18 5.67 7.41 7.56 7.14 6.50 5.53 5.76 6.08 4.61 5.33 6.44 6.46 6.11 5.79 6.26

6.25 5.01 4.07 3.60 4.38 5.63 5.79 5.01 5.48 5.63 5.48 5.01 3.76 3.29 3.92 4.54 5.17 4.07 6.25 6.87 7.33 6.72 5.48 4.38 4.86 4.54 3.44 4.86 5.48 5.48 5.01 4.70 5.94

5.47 4.32 3.72 3.36 3.67 4.62 4.83 4.10 4.28 4.36 4.19 3.89 3.41 3.02 2.74 3.03 3.76 3.70 5.23 6.38 6.08 5.51 3.93 3.63 4.10 3.96 2.75 4.05 4.59 4.52 4.33 4.19 5.02

6.42 5.49 4.87 4.71 5.02 6.11 6.11 5.64 5.96 5.80 5.49 5.33 4.87 4.24 4.71 5.18 5.80 5.64 7.03 7.03 7.19 6.73 4.56 4.87 4.71 4.09 3.62 4.56 4.87 5.33 5.02 5.02 6.88

5.66 4.53 4.10 4.07 4.32 5.13 5.17 4.70 4.80 4.65 4.44 4.42 4.07 3.61 3.63 3.79 4.43 4.70 5.93 6.63 6.06 5.13 3.33 3.44 3.61 3.43 2.67 3.77 3.97 4.00 3.88 3.93 5.31

5.29 4.19 3.72 3.25 3.73 4.83 4.83 4.36 4.52 4.36 4.36 4.04 3.73 2.94 3.42 3.73 4.20 4.36 5.61 5.61 6.38 5.29 3.88 4.04 3.88 3.25 2.93 3.88 4.51 4.98 4.51 4.51 5.91

195

4.59 3.33 2.88 2.77 3.13 3.93 4.13 3.67 3.69 3.46 3.42 3.35 3.01 2.65 2.65 2.78 3.30 3.52 4.63 5.30 4.88 3.79 2.62 2.70 2.88 2.73 2.19 3.17 3.30 3.39 3.27 3.35 4.53

4.32 3.06 2.58 2.11 2.90 3.84 4.01 3.37 3.37 3.22 3.53 3.22 1.94 1.63 2.58 2.90 3.53 3.69 5.26 4.79 5.57 4.01 3.53 3.84 3.69 2.90 2.74 3.53 4.32 4.63 4.32 4.16 5.26

3.70 2.33 1.92 1.77 2.10 2.84 2.99 2.47 2.47 2.24 2.14 2.04 1.62 1.28 1.38 1.65 2.30 2.50 4.01 4.43 3.90 2.94 2.26 2.38 2.51 2.38 1.95 2.82 2.96 3.09 2.98 3.04 3.88

3.79 3.17 3.02 3.02 3.33 3.02 1.75 1.59 2.70 2.86 3.33 2.86 4.57 3.95 4.88 3.33 3.33 3.33 3.33 2.54 2.38 3.17 3.64 4.11 3.79 3.64 4.57

2.94 2.15 1.91 1.86 1.85 1.76 1.42 1.17 1.22 1.58 2.05 2.21 3.43 3.54 3.05 2.44 1.96 2.06 2.16 2.06 1.75 2.42 2.54 2.70 2.64 2.73 3.35

2.12 1.81 1.81 2.12 2.12 1.97 1.81 1.97 2.12 1.81 1.97 1.97 2.28 1.97 1.97 1.81 1.49 1.49 1.97 1.81 1.81 1.81 1.81 1.81 1.81 1.97 2.12 2.44 2.28 2.92 4.02

1.88 1.49 1.60 1.98 2.05 1.69 1.61 1.83 1.84 1.61 1.84 1.94 1.92 1.84 1.82 1.53 1.44 1.49 1.69 1.66 1.63 1.63 1.67 1.70 1.69 1.83 1.89 2.15 2.17 2.27 2.61

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

03/03/04 03/04/04 03/05/04 03/06/04 03/07/04 03/08/04 03/09/04 03/10/04 03/11/04 03/12/04 03/13/04 03/14/04 03/15/04 03/16/04 03/17/04 03/18/04 03/19/04 03/20/04 03/21/04 03/22/04 03/23/04 03/24/04 03/25/04 03/26/04 03/27/04 03/28/04 03/29/04 03/30/04 03/31/04 04/01/04 04/02/04 04/03/04 04/04/04

7.27 8.19 7.42 9.43 10.83 11.91 11.76 12.07 11.91 12.53 12.69 12.69 12.53 13.31 13.62 13.00 13.62 13.31 14.08 15.02 15.97 15.02 14.23 13.00 12.07 13.16 14.08 14.39 13.62 12.69 13.92 16.13 17.56

6.39 7.38 7.03 7.87 9.17 10.29 10.62 10.60 10.50 10.87 11.34 11.58 11.18 11.63 11.93 11.93 12.28 11.84 12.38 13.61 14.24 13.83 13.20 12.06 11.22 10.81 11.81 12.38 12.58 10.96 11.43 13.61 15.35

6.41 6.87 6.10 8.42 10.12 10.89 10.74 11.20 10.89 11.66 11.82 11.51 11.66 11.97 12.43 12.12 13.06 12.43 13.36 13.67 15.23 13.67 13.36 12.12 11.04 12.43 13.67 14.76 13.21 12.90 14.13 16.18 17.45

5.35 5.96 5.41 6.53 7.91 8.87 9.12 9.20 9.09 9.54 9.92 9.99 9.82 9.92 10.34 10.60 11.13 10.57 11.14 12.07 12.88 12.36 11.72 10.83 9.93 9.91 11.11 12.35 12.15 10.60 11.32 13.27 14.91

6.88 6.73 6.57 8.42 9.80 10.42 9.96 10.42 9.96 11.04 10.73 10.88 10.73 11.04 11.66 11.66 12.12 11.81 12.42 12.89 13.96 12.73 12.12 11.50 10.88 12.27 13.35 14.43 13.35 12.42 13.50 14.90 15.69

5.75 5.93 5.64 6.87 7.92 8.61 8.72 8.82 8.61 9.26 9.27 9.47 9.32 9.40 9.85 10.22 10.63 10.11 10.58 11.41 12.09 11.60 11.05 10.49 9.67 10.01 11.12 12.28 11.97 10.49 11.47 12.95 14.11

6.07 5.76 5.60 7.77 9.01 9.48 9.17 9.63 9.17 10.41 10.09 10.09 10.09 10.25 10.87 11.03 11.33 10.87 11.64 12.11 13.04 11.64 11.18 10.41 9.79 11.33 12.88 13.66 12.42 11.03 12.73 14.12 15.22

196

4.63 4.71 4.51 5.84 6.80 7.43 7.48 7.62 7.33 8.05 7.95 8.15 8.05 8.07 8.56 9.01 9.30 8.58 9.12 9.98 10.58 10.07 9.49 9.12 8.33 8.74 9.84 11.08 10.67 9.20 10.28 11.74 12.84

5.10 4.63 4.79 6.97 8.06 8.67 8.52 8.98 8.37 9.45 9.14 9.14 9.45 9.61 10.23 10.54 10.54 10.07 11.01 11.31 12.40 10.69 10.38 9.45 9.29 11.01 12.09 13.18 11.01 10.69 12.24 13.49 14.57

3.65 3.71 3.50 5.00 5.89 6.41 6.48 6.67 6.31 7.02 6.91 7.18 7.08 7.10 7.59 8.03 8.26 7.51 8.14 8.94 9.55 8.94 8.40 8.15 7.42 7.88 8.88 10.21 9.64 8.32 9.35 10.72 11.93

4.57 3.79 4.42 6.28 7.22 7.52 7.37 7.68 7.22 8.14 7.83 7.83 8.14 8.14 8.76 8.76 9.37 8.76 9.37 9.52 10.76 8.76 9.52 8.29 8.29 9.52 10.46 11.84 9.52 10.30 7.37

3.10 3.20 3.16 4.41 5.17 5.42 5.59 5.63 5.44 5.94 5.88 6.20 6.01 6.10 6.50 6.95 6.92 6.38 7.03 7.65 8.18 7.60 7.24 7.15 6.60 6.97 7.94 9.12 8.47 7.46 6.97

2.92 2.92 3.23 3.55 2.92 3.08 3.23 3.39 3.23 3.39 3.55 3.55 3.71 3.71 3.86 4.02 4.17 4.17 4.33 4.33 4.64 4.64 4.96 4.64 4.96 5.11 5.42 5.73 5.42 4.96 5.58 5.73 5.73

2.40 2.63 2.90 3.09 2.68 2.61 2.72 2.85 2.86 2.96 3.03 3.14 3.17 3.22 3.34 3.51 3.59 3.67 3.84 3.95 4.12 4.19 4.29 4.27 4.44 4.50 4.86 5.22 4.95 4.72 5.02 5.27 5.48

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

04/05/04 04/06/04 04/07/04 04/08/04 04/09/04 04/10/04 04/11/04 04/12/04 04/13/04 04/14/04 04/15/04 04/16/04 04/17/04 04/18/04 04/19/04 04/20/04 04/21/04 04/22/04 04/23/04 04/24/04 04/25/04 04/26/04 04/27/04 04/28/04 04/29/04 04/30/04 05/01/04 05/02/04 05/03/04 05/04/04 05/05/04 05/06/04 05/07/04

18.04 17.88 17.24 16.44 15.18 15.49 15.97 16.28 15.81 14.39 13.62 14.23 15.18 15.02 14.86 14.23 12.69 14.54 16.13 15.97 16.92 18.04 18.21 17.08 15.65 17.40 19.18 20.64 21.63 21.80 21.13 21.13 20.97

16.25 16.65 15.63 14.48 13.52 13.41 13.67 14.12 14.30 13.18 12.20 12.13 13.18 13.16 13.60 12.93 11.65 11.63 13.65 14.06 14.45 15.48 16.30 13.93 12.80 14.49 16.27 17.87 19.04 19.57 18.94 18.98 19.06

18.09 16.34 13.52 13.21 12.74 12.59 13.21 13.67 13.36 12.12 11.51 11.82 13.52 13.67 13.21 11.82 10.58 13.52 14.13 14.29 14.92 15.87 16.02 13.82 14.29 15.87 17.61 18.41 19.22 20.35 19.22 18.41 19.22

15.37 14.20 11.87 11.62 10.98 10.76 10.99 11.35 11.59 10.81 9.73 9.59 11.02 11.04 11.12 10.56 9.66 10.42 11.90 12.06 12.23 13.01 13.59 12.02 11.24 12.75 14.17 15.22 15.91 16.66 16.24 15.73 16.08

15.69 13.96 11.34 10.88 10.42 10.42 10.58 10.73 10.11 9.33 9.03 9.64 9.96 10.27 9.64 9.64 8.72 11.34 11.34 11.19 11.81 12.42 12.12 11.04 11.81 12.42 13.19 13.50 13.81 13.96 13.81 13.35 13.96

14.09 10.69 9.60 9.23 8.72 8.62 8.80 8.91 8.68 8.28 7.71 7.91 8.40 8.35 8.33 8.33 7.87 8.73 9.25 9.27 9.38 9.88 10.09 9.03 9.30 10.01 10.64 11.14 11.47 11.72 11.60 11.47 11.68

14.59 12.57 10.72 10.25 9.94 9.96 10.12 10.25 9.32 8.70 8.54 9.17 9.34 9.96 9.03 9.18 8.26 10.72 11.03 10.72 11.18 11.80 11.64 9.79 11.33 11.96 12.57 12.88 13.19 13.19 13.04 12.57 13.19

197

12.61 9.48 8.78 8.36 7.94 7.86 7.99 8.08 7.82 7.51 7.05 7.28 7.58 7.65 7.56 7.66 7.29 8.19 8.55 8.53 8.70 9.13 9.31 8.29 8.76 9.33 9.85 10.27 10.55 10.73 10.66 10.56 10.76

13.18 11.31 10.23 9.92 9.61 9.61 9.76 9.92 8.83 8.52 8.52 8.83 8.67 9.45 8.67 8.67 7.90 10.38 10.54 10.07 10.69 11.16 11.01 9.29 10.85 11.47 11.93 12.24 12.56 12.40 12.40 11.93 12.40

11.43 8.60 8.13 7.64 7.30 7.35 7.46 7.46 7.20 6.95 6.66 6.80 7.00 7.12 7.03 7.15 6.84 7.70 7.94 7.91 8.14 8.48 8.63 7.78 8.28 8.74 9.18 9.52 9.76 9.88 9.86 9.78 10.02

9.06 8.76 8.60 9.06 8.91 8.91 8.14 7.68 7.98 8.29 7.83 8.60 7.98 8.14 7.52 9.21 9.52 9.21 9.68 9.99 9.99 8.91 9.83 10.30 10.76 10.92 11.07 10.92 11.07 10.92 11.22

8.06 6.72 6.48 6.66 6.70 6.65 6.49 6.28 6.20 6.30 6.35 6.55 6.46 6.61 6.42 7.14 7.27 7.25 7.50 7.77 7.86 7.32 7.78 8.05 8.41 8.67 8.83 8.94 8.99 8.94 9.17

5.89 5.58 5.95 5.42 5.42 6.20 5.89 5.58 5.73 5.42 5.58 5.73 5.73 5.89 5.89 6.20 6.20 6.20 6.67 6.51 6.67 6.82 6.82 6.98 7.13 7.13 7.44 7.44 7.59 7.75 7.91 7.91 8.06

5.50 5.48 5.34 5.17 5.13 5.52 5.39 5.36 5.44 5.31 5.41 5.54 5.55 5.70 5.80 5.93 5.97 6.05 6.29 6.34 6.52 6.63 6.75 6.76 6.96 6.98 7.24 7.31 7.40 7.52 7.63 7.79 7.91

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

05/08/04 05/09/04 05/10/04 05/11/04 05/12/04 05/13/04 05/14/04 05/15/04 05/16/04 05/17/04 05/18/04 05/19/04 05/20/04 05/21/04 05/22/04 05/23/04 05/24/04 05/25/04 05/26/04 05/27/04 05/28/04 05/29/04 05/30/04 05/31/04 06/01/04 06/02/04 06/03/04 06/04/04 06/05/04 06/06/04 06/07/04 06/08/04 06/09/04

20.31 18.37 17.72 14.08 14.70 16.61 18.37 17.56 17.24 16.44 16.28 16.44 18.21 17.40 17.72 17.24 17.88 19.02 18.04 17.24 16.61 15.97 17.88 18.86 19.83 20.97 22.30 23.31 23.13 21.63 19.51 20.31 19.18

18.52 17.00 14.83 12.88 13.46 14.09 15.96 15.48 15.07 15.46 15.17 15.22 16.00 16.81 16.41 15.94 15.69 16.87 16.96 16.56 15.86 14.77 15.87 17.02 18.01 18.86 20.08 20.94 21.47 19.82 17.93 18.06 18.01

18.09 16.49 14.29 13.36 14.13 15.87 16.97 14.92 16.18 15.55 14.44 15.55 17.29 16.49 16.49 15.71 16.97 17.77 15.87 15.55 14.76 14.44 16.49 17.45 18.41 19.06 19.54 20.84 20.35 19.72 17.79 18.59 16.83

16.05 14.58 12.90 11.67 12.13 12.95 14.34 13.51 13.57 13.90 13.46 13.60 14.82 15.21 14.81 14.03 14.29 15.29 14.88 14.35 13.85 13.12 13.98 15.35 16.06 16.78 17.51 18.28 18.36 17.53 16.00 16.03 15.64

13.50 12.73 11.66 10.88 11.96 13.35 13.96 12.58 13.66 13.04 12.12 13.66 14.58 13.50 13.66 13.35 14.43 14.90 13.66 13.04 12.89 13.04 14.90 15.22 15.69 16.16 16.47 16.79 16.32 16.01 14.58 15.84 14.58

11.61 11.04 10.23 9.91 10.45 10.96 11.64 10.97 11.58 11.48 11.13 11.79 12.36 12.37 11.96 11.74 12.17 12.69 12.02 12.21 12.07 11.58 12.29 13.00 13.45 13.76 14.13 14.44 14.36 14.05 13.09 13.48 12.86

12.73 12.11 10.56 10.25 11.64 12.88 13.19 11.33 12.88 12.57 11.33 13.04 13.81 12.88 12.88 12.88 13.81 14.28 12.42 12.57 12.57 12.42 16.65 17.92 19.22 15.54 15.54 16.02 15.54 15.38 13.97 15.22 13.19

198

10.68 10.21 9.49 9.36 9.89 10.32 10.86 10.18 10.91 10.71 10.42 11.12 11.54 11.45 11.13 11.02 11.44 11.90 11.15 11.51 11.45 10.55 11.80 13.80 13.91 12.93 13.17 13.48 13.37 13.14 12.27 12.76 12.12

12.09 11.62 9.61 9.92 11.31 12.40 12.87 10.69 12.40 12.09 10.85 12.56 13.33 12.24 12.24 12.56 13.33 13.79 11.47 12.24 12.24 12.09 13.79 14.11 14.57 14.89 14.89 15.37 14.89 14.42 13.49 14.73 12.71

9.94 9.59 8.97 8.98 9.48 9.85 10.31 9.67 10.40 10.19 9.96 10.62 10.95 10.78 10.53 10.52 10.95 11.32 10.58 11.00 11.00 10.63 11.29 11.73 12.06 12.26 12.44 12.72 12.65 12.43 11.72 12.22 11.64

10.92 10.61 8.91 9.52 10.61 11.38 11.69 10.14 11.53 11.22 10.30 11.69 12.47 11.38 11.53 11.69 12.47 12.78 10.76 11.69 11.69 11.53 12.78 12.93 13.39 13.70 13.70 14.01 13.54 13.54 12.62 13.70 12.31

9.13 8.92 8.50 8.60 9.04 9.31 9.64 9.15 9.76 9.60 9.46 10.02 10.25 10.01 9.97 10.00 10.38 10.63 10.04 10.40 10.37 10.23 10.76 11.05 11.30 11.43 11.60 11.80 11.72 11.59 11.11 11.53 11.13

8.06 8.21 8.37 8.52 8.52 8.67 8.67 8.83 8.83 8.83 9.13 9.13 9.13 9.29 9.44 9.44 9.59 9.75 9.59 9.75 9.91 9.91 9.91 10.07 10.07 10.22 10.22 10.22 10.38 10.38 10.38 10.53 10.53

8.00 8.02 8.18 8.29 8.36 8.44 8.54 8.63 8.74 8.79 8.93 8.94 9.01 9.10 9.20 9.24 9.35 9.46 9.50 9.59 9.64 9.70 9.80 9.93 9.94 10.03 10.09 10.17 10.21 10.27 10.28 10.36 10.40

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

06/10/04 06/11/04 06/12/04 06/13/04 06/14/04 06/15/04 06/16/04 06/17/04 06/18/04 06/19/04 06/20/04 06/21/04 06/22/04 06/23/04 06/24/04 06/25/04 06/26/04 06/27/04 06/28/04 06/29/04 06/30/04 07/01/04 07/02/04 07/03/04 07/04/04 07/05/04 07/06/04 07/07/04 07/08/04 07/09/04 07/10/04 07/11/04 07/12/04

17.72 19.51 20.15 22.30 21.80 20.64 20.97 22.13 20.97 22.63 22.47 23.13 23.82 23.48 24.34 24.34 24.68 24.51 24.17 23.64 22.30 22.80 23.82 22.97 23.13 22.80 23.13 22.97 21.97 21.80 22.80 22.63 23.31

16.24 16.87 18.06 19.59 19.79 18.89 18.30 19.44 19.47 19.87 20.35 20.61 21.36 21.71 22.09 22.07 22.71 22.47 22.47 21.90 20.51 20.70 21.63 21.66 21.42 20.97 21.35 21.41 19.96 19.91 20.55 20.71 21.03

15.24 17.95 18.11 20.04 19.88 19.40 18.92 20.04 18.76 20.04 20.21 20.53 19.08 18.92 19.08 20.21 20.53 20.37 19.88 19.56 19.24 19.88 20.04 19.56 19.72 19.40 19.08 19.72 18.92 17.95 19.40 19.56 19.88

14.02 15.19 16.09 17.40 17.47 16.79 16.28 17.15 16.89 17.30 17.83 17.78 17.37 17.53 17.62 18.10 18.74 18.70 18.50 17.95 17.34 18.00 18.51 18.13 18.07 17.83 17.84 17.98 17.34 16.92 17.53 18.06 18.16

13.50 15.69 15.53 16.47 16.16 15.84 16.16 16.63 15.22 16.79 16.32 16.47 16.79 16.79 16.16 17.27 17.27 17.11 16.63 16.79 16.94 17.58 17.58 16.79 17.42 17.42 17.11 17.58 17.11 16.32 17.58 17.58 18.07

12.47 13.24 13.54 14.23 14.15 13.84 13.73 14.18 13.65 14.26 14.27 14.28 14.30 14.43 14.22 14.79 14.94 14.99 14.80 14.80 14.79 15.03 15.24 14.90 15.16 15.01 15.08 15.29 14.93 14.72 15.35 15.37 15.57

12.88 15.22 15.07 15.86 15.54 15.38 15.54 16.02 14.59 16.18 15.70 15.86 16.18 16.18 15.54 16.49 16.65 16.65 16.02 16.49 16.49 16.81 16.81 16.02 16.81 16.81 16.49 16.81 16.65 15.70 16.81 16.97 17.44

199

11.81 12.64 12.80 13.43 13.30 13.06 13.00 13.40 12.84 13.54 13.42 13.48 13.60 13.71 13.54 14.10 14.19 14.26 14.06 14.17 14.15 14.28 14.50 14.18 14.46 14.36 14.40 14.57 14.24 14.04 14.67 14.68 14.89

12.40 14.73 14.57 15.37 15.05 14.89 15.05 15.37 13.95 15.53 15.21 15.21 15.53 15.68 15.05 15.84 16.00 16.00 15.53 16.00 16.00 16.16 16.32 15.68 16.32 16.32 16.00 16.48 16.16 15.21 16.32 16.63 16.95

11.40 12.20 12.28 12.81 12.67 12.48 12.48 12.77 12.28 12.98 12.81 12.89 13.07 13.13 13.01 13.52 13.58 13.65 13.48 13.61 13.59 13.67 13.94 13.68 13.95 13.86 13.88 14.05 13.79 13.60 14.20 14.19 14.41

12.00 13.70 13.70 14.01 13.85 13.85 14.01 14.16 13.24 14.32 14.01 14.01 14.32 14.47 13.85 14.63 14.63 14.78 14.78 14.94 15.10 15.10 15.10 14.63 15.10 15.26 14.94 15.26 15.26 14.32 15.26 15.57 15.73

10.92 11.60 11.61 11.99 11.88 11.75 11.82 12.02 11.63 12.22 12.05 12.14 12.34 12.38 12.35 12.72 12.77 12.87 12.75 12.80 12.89 12.97 13.19 13.03 13.22 13.20 13.21 13.38 13.21 13.06 13.56 13.55 13.74

10.53 10.69 10.69 10.84 10.84 10.84 11.00 11.00 11.00 11.00 11.16 11.16 11.31 11.31 11.46 11.46 11.62 11.77 11.77 11.93 11.93 12.08 12.08 12.08 12.23 12.23 12.23 12.39 12.39 12.54 12.54 12.70 12.86

10.44 10.50 10.55 10.60 10.64 10.68 10.76 10.79 10.83 10.90 10.91 11.04 11.15 11.22 11.25 11.40 11.49 11.58 11.64 11.71 11.82 11.88 11.97 12.02 12.06 12.15 12.22 12.30 12.32 12.43 12.47 12.52 12.66

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

07/13/04 07/14/04 07/15/04 07/16/04 07/17/04 07/18/04 07/19/04 07/20/04 07/21/04 07/22/04 07/23/04 07/24/04 07/25/04 07/26/04 07/27/04 07/28/04 07/29/04 07/30/04 07/31/04 08/01/04 08/02/04 08/03/04 08/04/04 08/05/04 08/06/04 08/07/04 08/08/04 08/09/04 08/10/04 08/11/04 08/12/04 08/13/04 08/14/04

24.51 25.03 24.68 25.03 25.73 24.51 24.17 24.68 24.68 24.17 24.17 24.51 24.68 25.03 24.17 24.17 24.17 24.34 24.68 25.21 25.21 24.68 24.17 23.82 23.48 22.63 22.47 22.80 23.48 23.99 24.17 23.82 23.13

22.07 22.79 22.92 23.02 23.90 22.86 22.20 22.63 23.04 22.58 22.37 22.59 23.24 23.26 22.58 22.31 22.35 22.43 22.70 23.10 23.36 22.96 22.37 22.16 22.00 21.13 20.65 20.75 21.49 22.02 22.28 22.33 22.42

20.69 20.86 20.35 20.68 21.67 20.03 20.51 20.84 21.01 20.84 20.84 21.01 21.33 20.68 20.68 20.51 20.68 20.68 21.01 21.33 21.50 20.84 20.51 20.35 20.19 19.87 19.87 20.03 20.51 20.84 21.01 21.19 20.86

18.96 19.29 19.18 19.22 19.93 19.24 18.62 19.39 19.55 19.45 19.35 19.53 20.05 19.62 19.21 19.21 19.17 19.14 19.54 19.90 20.17 19.62 19.24 19.30 19.14 18.68 18.42 18.64 19.24 19.58 19.67 19.92 20.02

18.39 18.39 18.07 18.55 18.39 17.42 18.71 18.71 19.03 18.71 18.87 19.03 18.87 18.07 18.87 18.71 18.87 19.03 19.19 19.36 19.03 19.19 19.19 19.19 18.71 18.71 19.03 19.36 19.68 19.84 19.84 19.68 19.19

16.05 16.10 16.11 16.32 16.47 15.87 16.17 16.56 16.67 16.57 16.59 16.73 16.88 16.44 16.77 16.70 16.72 16.80 17.05 17.23 17.32 17.17 17.09 17.16 16.98 16.89 16.86 17.18 17.50 17.72 17.74 17.82 17.90

17.76 17.76 17.44 17.92 17.44 15.86 17.92 18.08 18.24 18.08 18.24 18.41 18.24 17.44 18.24 18.24 18.24 18.41 18.57 18.57 18.57 18.57 18.73 18.57 18.24 18.24 18.73 19.06 19.22 19.38 19.38 19.38 18.73

200

15.28 15.34 15.32 15.55 15.60 15.03 15.50 15.84 15.87 15.80 15.83 15.96 16.11 15.71 16.04 15.98 16.03 16.11 16.32 16.47 16.57 16.45 16.42 16.49 16.33 16.32 16.34 16.62 16.90 17.09 17.14 17.22 17.24

17.11 17.27 16.79 17.27 16.95 15.21 17.27 17.43 17.75 17.59 17.75 17.91 17.59 16.95 17.75 17.75 17.75 17.91 18.23 18.23 18.07 18.23 18.23 18.23 18.07 18.07 18.39 18.72 18.88 19.04 19.04 19.04 18.39

14.71 14.78 14.76 14.95 15.01 14.52 15.03 15.31 15.32 15.28 15.32 15.44 15.55 15.25 15.56 15.52 15.56 15.67 15.86 15.96 16.08 16.01 16.01 16.09 15.98 16.01 16.07 16.32 16.56 16.74 16.79 16.89 16.88

15.89 16.21 15.89 14.01

13.96 14.04 14.01 13.21

17.47 17.47 17.31 17.31 17.63 17.95 18.11 18.27 18.27 18.27 17.79

16.27 15.59 15.54 15.59 15.70 15.89 16.08 16.23 16.31 16.41 16.39

12.86 12.86 13.01 13.40 13.40 13.40 13.56 13.71 13.71 13.71 13.86 13.86 14.02 14.02 14.17 14.17 14.33 14.33 14.48 14.64 14.64 14.64 14.80 14.96 14.96 14.96 15.28 15.28 15.44 15.59 15.59 15.76 15.91

12.75 12.80 12.92 13.05 13.23 13.27 13.38 13.48 13.55 13.62 13.70 13.77 13.84 13.92 14.02 14.09 14.17 14.22 14.31 14.39 14.47 14.53 14.64 14.70 14.83 14.88 15.08 15.11 15.26 15.39 15.49 15.57 15.70

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

08/15/04 08/16/04 08/17/04 08/18/04 08/19/04 08/20/04 08/21/04 08/22/04 08/23/04 08/24/04 08/25/04 08/26/04 08/27/04 08/28/04 08/29/04 08/30/04 08/31/04 09/01/04 09/02/04 09/03/04 09/04/04 09/05/04 09/06/04 09/07/04 09/08/04 09/09/04 09/10/04 09/11/04 09/12/04 09/13/04 09/14/04 09/15/04 09/16/04

23.64 23.13 22.47 23.48 23.64 23.82 23.48 22.63 19.83 19.83 19.83 19.34 20.15 20.64 21.47 21.80 22.13 21.97 20.31 18.21 19.02 19.18 19.34 19.34 19.99 20.15 20.31 19.99 19.51 18.04 17.72 16.92 17.40

22.12 22.28 21.73 21.83 22.26 22.25 22.12 20.51 18.62 18.54 18.87 18.40 18.48 18.87 19.56 19.94 20.31 20.57 18.39 16.83 17.14 17.72 17.70 17.75 18.24 18.64 18.82 18.72 18.54 16.94 16.45 16.04 15.99

20.86 20.86 20.37 21.19 21.53 22.53 22.36 20.86 19.56 19.40 19.56 19.24 19.72 20.53 21.19 21.53 22.19 21.86 19.88 18.73 19.38 19.71 19.22 19.71 20.35 20.35 21.01 20.35 19.06 17.45 17.77 16.97 18.57

19.85 20.20 19.62 19.77 20.43 20.74 20.68 19.47 18.16 18.15 18.40 18.03 18.05 18.64 19.25 19.62 20.09 20.26 18.66 16.90 17.21 17.68 17.51 17.76 18.28 18.59 18.69 18.56 18.04 16.68 16.30 16.22 16.78

19.68 19.19 18.55 20.48 20.48 20.81 20.64 19.68 19.36 19.03 19.03 19.19 19.84 20.16 20.64 20.97 21.30 20.64 19.84 19.03 19.68 19.68 20.00 20.16 20.48 20.32 20.32 20.32 19.84 18.23 18.71 18.07 19.36

17.92 17.99 17.64 18.38 18.68 18.94 18.89 17.91 17.73 17.75 18.07 17.76 18.00 18.37 18.78 19.07 19.36 19.39 18.04 17.35 17.90 18.25 18.22 18.52 18.87 18.91 18.94 18.90 18.30 17.49 17.49 17.37 17.86

19.22 18.89 18.08 20.03 20.03 20.36 20.03 18.57 19.06 18.73 18.73 19.06 19.87 20.03 20.36 20.84 21.01 20.52 19.06 19.22 19.71 19.71 20.03 20.19 20.52 20.19 20.36 20.36 19.38 18.24 18.89 18.08 19.38

201

17.35 17.41 17.09 17.88 18.05 18.23 18.16 17.27 17.37 17.28 17.59 17.44 17.66 17.98 18.35 18.61 18.84 18.82 17.63 17.19 17.71 18.00 18.02 18.28 18.61 18.59 18.65 18.58 17.91 17.34 17.42 17.20 17.74

18.88 18.72 18.07 19.70 19.86 20.03 19.86 17.75 19.21 18.88 18.72 19.21 19.86 20.03 20.35 20.67 20.84 20.35 18.88 19.37 20.03 20.03 20.35 20.35 20.51 20.35 20.51 20.19 18.88 18.39 19.21 18.23 19.54

17.02 17.08 16.83 17.54 17.66 17.82 17.75 16.97 17.25 17.13 17.41 17.36 17.60 17.86 18.18 18.42 18.58 18.54 17.51 17.29 17.81 18.04 18.08 18.29 18.54 18.51 18.57 18.48 17.83 17.45 17.56 17.28 17.78

18.11 17.95 17.47 18.92 19.08 19.24 19.08 17.31 18.92 18.59 18.43 19.08 19.56 19.56 19.89 20.05 20.21 19.89 18.76 19.24 19.73 19.73 20.05 20.21 20.21 20.21 20.05 19.89 18.27 18.43 19.24 18.27 19.56

16.56 16.63 16.50 17.07 17.15 17.28 17.23 16.70 17.12 16.97 17.20 17.22 17.47 17.64 17.88 18.06 18.17 18.18 17.46 17.48 17.87 17.99 18.09 18.22 18.39 18.34 18.40 18.30 17.77 17.63 17.70 17.38 17.83

15.91 16.07 16.23 16.23 16.39 16.54 16.54 16.71 16.86 16.86 17.02 17.18 17.34 17.50 17.66 17.66 17.82 17.82 17.82 17.98 18.14 18.14 18.31 18.31 18.31 18.47 18.63 18.63 18.14 18.14 18.31 17.82 18.14

15.81 15.90 16.02 16.14 16.24 16.37 16.47 16.52 16.66 16.76 16.85 17.00 17.13 17.23 17.34 17.43 17.54 17.63 17.64 17.76 17.89 17.90 18.04 18.08 18.07 18.07 18.13 18.08 17.93 17.89 17.89 17.71 17.73

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

09/17/04 09/18/04 09/19/04 09/20/04 09/21/04 09/22/04 09/23/04 09/24/04 09/25/04 09/26/04 09/27/04 09/28/04 09/29/04 09/30/04 10/01/04 10/02/04 10/03/04 10/04/04 10/05/04 10/06/04 10/07/04 10/08/04 10/09/04 10/10/04 10/11/04 10/12/04 10/13/04 10/14/04 10/15/04 10/16/04 10/17/04 10/18/04 10/19/04

17.88 17.72 16.44 15.97 15.81 16.28 17.40 18.04 18.21 18.21 18.53 18.53 18.53 18.04 17.72 17.56 17.40 17.08 16.61 15.81 17.08 16.92 16.44 15.02 14.23 14.23 14.70 15.18 15.02 15.02 14.54 13.62 12.53

16.86 16.72 15.54 14.96 14.63 14.81 15.89 16.67 16.83 16.89 17.10 17.17 17.25 16.79 16.60 16.39 16.19 15.94 15.53 14.88 15.66 15.78 15.70 13.86 13.18 13.20 13.60 13.90 14.03 13.98 13.85 12.66 11.64

18.73 17.77 16.49 16.18 15.87 16.34 17.45 17.93 18.57 18.73 19.06 18.73 18.41 17.93 17.61 17.61 17.29 17.29 16.65 15.87 16.81 16.65 16.18 14.60 14.13 14.29 15.07 15.39 15.07 15.07 14.44 13.36 12.43

17.38 16.83 15.61 15.29 14.99 15.12 16.29 16.79 17.01 17.02 17.30 17.20 17.06 16.77 16.49 16.39 16.17 15.93 15.51 14.93 15.64 15.65 15.42 13.50 12.96 13.09 13.64 13.79 13.73 13.80 13.90 12.85 11.64

19.36 18.55 18.07 17.74 17.42 18.07 18.55 18.87 18.87 18.71 18.87 18.71 18.39 18.23 18.07 17.91 17.58 17.27 16.79 16.32 16.94 16.79 16.47 14.90 14.90 15.06 15.22 15.22 15.37 15.53 15.06 14.12 13.19

18.08 17.08 16.68 16.40 16.21 16.53 17.30 17.44 17.48 17.53 17.71 17.55 17.36 17.10 16.92 16.75 16.54 16.27 15.94 15.42 15.89 15.73 15.36 13.90 13.92 14.08 14.28 14.17 14.31 14.56 14.48 13.35 12.49

19.55 18.08 18.08 17.92 17.61 18.24 18.57 18.73 18.89 18.73 18.73 18.57 18.41 18.08 17.92 17.76 17.44 17.28 16.65 16.02 16.65 16.49 16.02 14.75 14.91 14.91 15.22 15.22 15.22 15.07 14.59 13.51 12.57

202

17.85 16.79 16.61 16.38 16.14 16.46 17.13 17.20 17.22 17.25 17.36 17.21 17.00 16.80 16.60 16.41 16.17 15.92 15.57 15.02 15.56 15.32 14.89 13.64 13.67 13.79 13.95 13.82 13.97 14.06 13.88 12.80 11.95

19.70 17.75 18.07 18.07 17.91 18.39 18.72 18.88 19.04 18.88 18.88 18.56 18.23 18.23 17.91 17.91 17.43 17.27 16.79 15.84 16.63 16.48 15.68 14.89 14.89 15.05 15.21 15.21 15.21 15.05 13.79 12.87 12.09

17.83 16.76 16.73 16.53 16.30 16.58 17.10 17.12 17.12 17.15 17.20 17.04 16.81 16.69 16.44 16.26 16.00 15.76 15.40 14.81 15.38 15.09 14.67 13.62 13.62 13.71 13.78 13.64 13.76 13.63 13.42 12.43 11.54

19.56 17.31 18.11 18.27 18.11 18.43 18.59 18.76 18.76 18.59 18.59 18.43 17.95 18.11 17.79 17.63 17.31 17.15 16.67 15.89 16.52 16.21 15.41 15.26 15.03 15.03 15.03 15.03 14.87 14.72 13.79 13.02 12.24

17.78 16.86 16.91 16.77 16.59 16.75 17.04 17.01 16.98 16.99 16.97 16.85 16.61 16.60 16.31 16.12 15.86 15.67 15.29 14.77 15.22 14.88 14.53 13.78 13.72 13.75 13.71 13.59 13.65 13.39 13.18 12.44 11.60

18.14 17.50 17.50 17.50 17.34 17.34 17.34 17.18 17.18 17.18 17.02 17.02 16.86 16.86 16.54 16.39 16.07 15.91 15.59 15.28 15.12 14.96 14.64 14.64 14.33 14.17 14.17 14.02 13.86 13.71 13.56 13.56 12.93

17.66 17.42 17.34 17.22 17.06 16.94 16.89 16.78 16.75 16.74 16.62 16.59 16.46 16.39 16.03 15.90 15.66 15.48 15.18 14.88 14.74 14.61 14.36 14.14 13.97 13.85 13.65 13.57 13.45 13.28 13.26 13.18 12.80

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

10/20/04 10/21/04 10/22/04 10/23/04 10/24/04 10/25/04 10/26/04 10/27/04 10/28/04 10/29/04 10/30/04 10/31/04 11/01/04 11/02/04 11/03/04 11/04/04 11/05/04 11/06/04 11/07/04 11/08/04 11/09/04 11/10/04 11/11/04 11/12/04 11/13/04 11/14/04 11/15/04 11/16/04 11/17/04 11/18/04 11/19/04 11/20/04 11/21/04

13.62 13.16 12.69 12.22 12.22 11.29 10.67 12.07 12.07 11.91 11.29 10.36 9.74 9.89 9.89 10.36 10.36 9.58 9.27 9.27 9.58 9.89 10.83 11.44 11.14 10.83 10.21 10.21 9.74 9.74 8.81 7.57 6.80

12.34 12.56 12.07 11.86 11.33 10.51 10.30 11.05 11.76 11.46 10.84 9.66 8.91 9.39 9.61 9.47 9.54 9.13 9.05 9.12 9.29 9.58 10.41 10.79 10.87 10.51 9.73 9.79 9.35 9.53 8.17 6.90 6.12

13.21 12.59 12.28 11.66 11.20 10.43 10.43 11.66 11.66 10.89 10.43 9.96 9.03 9.64 9.34 9.96 9.80 8.88 8.88 8.72 9.03 9.34 9.96 10.89 9.96 9.80 9.18 9.49 8.72 9.03 8.42 6.87 5.94

12.27 12.15 11.66 11.47 10.58 9.78 9.99 11.03 11.31 10.65 10.08 9.03 7.97 8.58 9.03 9.10 8.87 8.52 8.57 8.50 8.50 8.86 9.57 10.03 9.63 9.33 8.65 8.94 8.36 8.53 7.26 6.14 5.17

13.96 13.19 13.04 12.73 12.58 11.66 12.12 12.73 12.58 11.81 11.50 10.88 9.80 10.73 9.80 10.88 11.19 10.58 10.42 10.27 10.27 10.58 10.88 11.04 10.27 10.27 9.80 9.96 9.33 9.80 8.88 8.11 7.03

12.89 12.60 12.45 12.19 11.47 10.92 11.37 12.02 11.90 11.27 11.00 10.01 8.97 9.69 9.59 10.00 10.11 9.88 9.85 9.64 9.61 9.99 10.35 10.56 9.88 9.70 9.10 9.37 8.89 9.13 8.19 7.20 6.27

13.51 12.73 12.57 12.27 12.11 11.33 11.49 12.11 11.96 11.03 10.87 10.25 9.17 10.25 9.32 10.56 10.56 10.25 9.94 9.63 9.94 10.09 10.25 10.41 9.63 9.63 9.17 9.32 8.54 9.32 8.39 7.31 6.69

203

12.42 12.12 11.94 11.55 10.90 10.36 10.68 11.38 11.17 10.65 10.33 9.36 8.34 9.18 9.16 9.62 9.50 9.24 9.23 8.98 9.03 9.27 9.73 9.81 9.00 8.88 8.33 8.58 8.05 8.40 7.56 6.41 5.56

13.02 12.56 11.93 11.47 11.31 10.85 10.69 11.62 11.16 10.38 10.07 9.45 8.98 9.29 9.29 9.92 9.61 9.61 9.29 8.52 9.14 9.14 9.45 9.29 8.52 8.52 8.37 8.37 7.74 8.37 7.59 6.19 5.72

12.06 11.75 11.49 10.99 10.38 9.80 9.93 10.73 10.46 10.01 9.65 8.70 7.87 8.73 8.90 9.08 8.75 8.52 8.60 8.27 8.32 8.51 8.96 8.91 8.12 8.07 7.52 7.77 7.21 7.59 6.78 5.61 4.80

13.02 12.71 12.24 11.47 11.93 11.32 10.85 11.47 11.01 10.54 10.08 9.92 9.46 9.46 9.46 10.08 10.23 9.92 9.61 8.69 9.31 9.15 9.31 8.84 8.22 8.38 8.38 8.22 7.92 8.53 7.76 6.68 6.37

12.05 11.84 11.59 11.10 10.62 10.05 9.89 10.67 10.43 10.14 9.70 8.85 8.30 8.76 8.99 9.20 8.76 8.70 8.73 8.43 8.39 8.44 8.84 8.53 8.00 7.96 7.46 7.79 7.29 7.59 6.97 5.91 5.25

13.09 12.93 12.47 12.00 11.84 11.69 11.53 11.69 11.53 10.76 10.61 10.45 10.45 10.76

12.79 12.52 12.20 11.74 11.57 11.25 11.36 11.44 11.05 10.56 10.29 10.28 9.94 9.92

8.98 8.67 8.83 8.37 8.21 8.06 8.21 8.37 8.06 8.06 8.12 7.97 7.66 7.50

8.78 8.51 8.43 8.05 7.97 8.00 8.04 8.17 8.06 7.96 7.85 7.66 7.38 7.17

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

11/22/04 11/23/04 11/24/04 11/25/04 11/26/04 11/27/04 11/28/04 11/29/04 11/30/04 12/01/04 12/02/04 12/03/04 12/04/04 12/05/04 12/06/04 12/07/04 12/08/04 12/09/04 12/10/04 12/11/04 12/12/04 12/13/04 12/14/04 12/15/04 12/16/04 12/17/04 12/18/04 12/19/04 12/20/04 12/21/04 12/22/04 12/23/04 12/24/04

6.64 7.57 7.73 8.50 8.34 7.73 6.64 5.24 4.77 5.55 5.39 6.02 5.71 4.77 5.86 7.11 7.42 8.50 9.58 9.74 9.43 8.96 8.50 7.73 7.11 7.11 6.96 6.80 6.49 5.71 6.02 5.24 4.62

6.14 6.86 7.26 8.03 7.96 7.39 5.73 4.63 4.41 4.92 5.12 5.77 5.09 4.38 5.25 6.47 7.10 7.93 9.01 9.62 9.09 8.68 8.07 7.19 6.58 6.79 6.90 6.56 6.29 5.17 5.31 4.60 4.12

5.94 6.56 7.18 7.64 7.49 6.56 5.63 4.38 3.76 4.38 4.86 5.01 4.70 4.07 5.01 6.10 6.10 7.03 8.72 8.72 8.57 8.11 7.18 6.56 5.79 5.94 5.79 5.63 5.17 4.38 4.23 3.44 3.60

5.24 5.64 6.41 7.09 6.88 6.20 4.87 3.61 3.25 3.87 4.34 4.65 3.87 3.43 4.42 5.36 5.82 6.59 7.95 8.45 8.13 7.43 6.76 5.87 5.41 5.59 5.58 5.32 4.79 3.74 3.58 2.98 2.81

7.50 7.50 8.42 8.57 7.96 7.50 6.88 5.64 5.18 5.80 6.11 6.11 5.64 5.80 6.11 6.88 7.19 7.96 9.33 9.18 8.88 8.27 7.81 7.19 6.88 6.88 6.73 6.42 6.26 5.64 5.96 5.49 5.96

6.57 6.70 7.54 7.91 7.41 6.96 5.56 4.74 4.55 5.12 5.73 5.65 4.82 4.67 5.53 6.29 6.68 7.13 8.45 8.78 8.16 7.70 7.29 6.53 6.25 6.35 6.35 6.02 5.68 4.80 5.11 4.83 4.94

6.84 6.84 7.77 8.08 7.62 6.84 5.91 4.98 4.51 5.44 5.60 5.44 5.13 4.98 5.29 6.22 6.22 7.00 8.54 8.39 7.62 7.31 7.00 6.22 6.07 5.76 5.76 5.60 5.44 4.35 4.35 3.88 4.19

204

5.83 5.96 6.80 7.20 6.73 6.22 4.81 4.00 3.85 4.55 5.06 4.96 4.18 4.01 4.81 5.48 5.73 6.33 7.62 7.82 7.02 6.61 6.27 5.43 5.22 5.30 5.20 4.96 4.67 3.53 3.44 3.11 3.17

6.03 6.35 6.66 6.97 6.66 5.72 4.63 4.01 3.53 4.63 4.63 4.47 4.01 4.01 4.32 5.10 5.10 6.03 7.59 7.13 6.51 6.19 5.88 5.26 4.94 4.63 4.47 4.32 4.16 3.22 3.37 2.74 3.06

5.06 5.17 5.98 6.41 5.99 5.39 3.96 3.25 3.07 3.80 4.26 4.13 3.39 3.23 3.91 4.56 4.85 5.47 6.70 6.84 5.96 5.60 5.30 4.52 4.26 4.32 4.18 4.01 3.72 2.57 2.53 2.22 2.33

6.22 6.68 6.53 6.84 7.14 6.07 5.29 4.66 3.88 4.98 4.82 4.66 4.66 4.35 4.51 5.13 4.82 5.76 7.46 6.68 5.76 6.07 5.60 5.29 4.98 4.51 4.51 4.35 4.19 3.26 3.57 3.09 3.57

5.49 5.53 6.19 6.44 6.14 5.61 4.31 3.82 3.62 4.33 4.62 4.38 3.75 3.69 4.17 4.54 4.75 5.29 6.35 6.40 5.60 5.33 5.09 4.44 4.24 4.26 4.14 4.04 3.75 2.74 2.76 2.47 2.57

7.35 7.35 7.19 7.04 7.19 6.88 6.73 6.42 6.11 6.11 5.95 5.79 5.79 5.63 5.32 5.48 5.17 5.32 5.63 5.32 5.32 5.48 5.32 5.32 5.17 4.85 5.01 4.69 4.69 4.38 4.54 4.07 4.07

7.07 7.09 6.94 6.94 6.89 6.62 6.43 6.19 5.93 5.93 5.83 5.70 5.50 5.30 5.27 5.23 5.17 5.20 5.29 5.25 5.21 5.21 5.09 4.99 4.88 4.75 4.69 4.60 4.51 4.24 4.16 3.93 3.83

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

12/25/04 12/26/04 12/27/04 12/28/04 12/29/04 12/30/04 12/31/04 01/01/05 01/02/05 01/03/05 01/04/05 01/05/05 01/06/05 01/07/05 01/08/05 01/09/05 01/10/05 01/11/05 01/12/05 01/13/05 01/14/05 01/15/05 01/16/05 01/17/05 01/18/05 01/19/05 01/20/05 01/21/05 01/22/05 01/23/05 01/24/05 01/25/05 01/26/05

4.77 4.93 5.39 5.39 6.18 6.33 6.02 5.86 5.39 5.24 4.62 3.52 3.83 3.68 4.46 5.55 5.71 5.86 4.93 4.93 4.46 4.14 4.93 5.39 6.96 6.80 6.33 6.18 5.86 6.33 6.33 6.18 6.33

4.11 4.47 4.75 4.80 5.68 5.98 5.69 5.63 5.09 4.69 4.03 3.08 3.42 3.48 3.82 4.75 5.18 5.31 4.40 4.25 3.93 3.67 4.42 5.10 6.17 6.38 6.25 6.01 5.72 6.06 6.14 5.91 5.83

3.60 3.92 4.23 4.38 4.86 5.32 4.86 4.38 4.23 3.92 3.44 2.50 2.50 2.66 3.44 4.54 4.70 4.38 3.76 3.44 3.13 2.97 3.44 4.23 5.94 5.17 5.32 4.86 4.70 5.32 4.07 4.70 4.86

2.91 3.36 3.54 3.64 4.40 4.67 4.31 4.05 3.62 3.37 2.91 2.01 2.09 2.35 2.82 3.52 3.78 3.72 3.05 2.66 2.36 2.27 2.95 3.60 4.79 4.78 4.86 4.50 4.39 4.52 3.86 4.00 4.01

5.64 5.96 6.42 6.57 6.88 6.73 6.42 6.26 5.96 5.80 5.64 4.87 4.56 4.71 5.49 6.26 6.26 5.64 5.18 4.87 4.87 5.02 5.33 6.26 7.03 6.73 6.57 6.42 5.96 6.11 5.64 5.64 6.11

4.82 5.20 5.52 5.55 6.29 6.17 5.76 5.46 5.18 5.26 4.67 3.93 3.94 4.25 4.58 5.19 5.26 5.07 4.47 4.08 4.07 3.99 4.43 5.23 6.13 5.98 5.86 5.64 5.42 5.44 4.84 5.11 5.29

4.04 4.67 4.98 4.82 5.29 5.13 4.67 4.19 4.35 4.35 3.57 2.93 2.77 3.09 3.57 4.82 4.35 4.04 3.72 3.41 3.25 3.41 3.57 4.51 5.60 5.13 4.98 4.51 4.19 4.35 3.57 4.04 4.82

205

3.11 3.63 3.84 3.93 4.70 4.53 4.01 3.66 3.43 3.58 2.94 2.27 2.27 2.65 2.82 3.51 3.42 3.26 2.71 2.45 2.35 2.18 2.68 3.38 4.43 4.30 4.23 3.86 3.64 3.61 2.89 3.31 3.66

3.22 3.37 3.84 3.69 4.16 4.01 3.53 3.22 3.22 3.22 2.27 1.79 1.63 1.94 2.27 3.53 3.06 2.90 2.42 2.42 2.11 2.11 2.27 3.22 4.32 4.01 3.69 3.06 2.90 2.90 2.42 2.90 3.53

2.36 2.82 2.98 3.04 3.78 3.56 3.01 2.71 2.51 2.62 1.93 1.31 1.30 1.65 1.83 2.53 2.37 2.20 1.65 1.48 1.34 1.17 1.67 2.37 3.38 3.21 3.15 2.73 2.55 2.52 1.80 2.26 2.60

3.41 3.41 3.88 3.73 3.88 3.88 3.26 3.41 3.41 3.09 2.31 1.99 1.83 1.83 2.31 3.26 3.09 2.62 2.14 2.62 2.31 2.14 1.99 2.94 3.88 3.73 3.41 2.62 2.78 2.78 2.31 2.62 3.09

2.62 2.97 3.02 3.11 3.64 3.38 2.90 2.69 2.54 2.64 2.05 1.62 1.57 1.63 1.82 2.34 2.20 2.14 1.56 1.57 1.44 1.26 1.66 2.21 3.00 2.84 2.90 2.50 2.36 2.31 1.74 2.14 2.33

4.07 3.91 3.91 3.75 3.75 3.59 3.59 3.59 3.44 3.12 2.96 2.96 2.81 2.64 2.64 2.81 2.64 2.49 2.49 2.64 2.17 2.01 2.01 2.33 2.49 2.64 2.33 2.17 2.17 2.17 2.17 2.17 2.17

3.73 3.65 3.61 3.53 3.54 3.46 3.35 3.28 3.16 3.00 2.80 2.84 2.75 2.47 2.53 2.56 2.37 2.32 2.33 2.27 1.88 1.76 1.89 2.08 2.09 2.09 2.10 2.08 2.06 2.02 1.91 1.96 1.97

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

01/27/05 01/28/05 01/29/05 01/30/05 01/31/05 02/01/05 02/02/05 02/03/05 02/04/05 02/05/05 02/06/05 02/07/05 02/08/05 02/09/05 02/10/05 02/11/05 02/12/05 02/13/05 02/14/05 02/15/05 02/16/05 02/17/05 02/18/05 02/19/05 02/20/05 02/21/05 02/22/05 02/23/05 02/24/05 02/25/05 02/26/05 02/27/05 02/28/05

7.27 7.27 7.73 7.57 6.64 6.49 6.49 6.64 5.86 6.49 5.71 7.11 7.27 6.49 6.64 6.02 7.88 7.73 7.88 6.80 6.18 6.02 6.18 6.33 7.57 8.34 9.12 9.12 9.27 9.58 9.74 9.74 9.89

6.65 6.90 7.00 6.73 6.01 5.57 5.68 5.70 5.44 5.68 5.21 6.01 6.35 5.67 5.49 5.29 6.45 7.28 7.02 5.87 5.04 4.77 5.07 5.93 6.83 7.58 7.64 7.67 8.03 8.20 8.31 8.43 8.90

5.79 5.79 6.72 6.10 5.01 5.48 5.32 5.48 4.54 5.17 4.54 5.94 5.94 5.32 5.63 4.70 6.72 6.41 6.72 5.48 5.17 5.17 5.01 5.32 6.10 6.87 7.64 8.42 8.42 8.72 8.88 9.03 8.88

4.96 5.26 5.66 5.05 4.41 4.20 4.30 4.32 4.03 4.15 3.90 4.55 4.62 4.14 4.17 3.88 5.07 5.71 5.48 4.12 3.55 3.47 3.73 4.58 5.14 5.95 6.08 6.59 6.67 6.85 7.01 7.09 7.30

6.57 7.19 7.65 7.03 6.42 6.57 6.42 6.57 6.11 6.73 6.42 6.73 6.57 6.42 6.26 6.11 7.50 7.34 7.34 6.11 5.96 5.96 6.26 6.73 7.34 7.50 8.72 8.72 9.03 9.49 9.33 9.64 9.03

5.88 6.14 6.61 5.94 5.62 5.65 5.51 5.54 5.37 5.48 5.24 5.70 5.60 5.33 5.27 5.23 6.08 6.66 6.20 4.95 4.66 4.63 5.02 5.89 6.20 6.68 7.34 7.22 7.30 7.83 7.62 7.74 7.79

4.98 5.60 5.76 5.44 4.67 5.13 5.13 5.13 4.67 5.13 4.67 5.44 5.44 4.98 5.13 4.67 6.07 5.76 5.44 4.82 4.82 4.82 4.67 4.98 5.76 5.44 7.62 6.84 7.00 7.77 7.62 7.77 7.00

206

4.15 4.49 4.86 4.09 3.75 3.87 3.80 3.77 3.59 3.78 3.40 3.98 3.90 3.49 3.57 3.43 4.32 4.80 4.34 3.31 3.06 3.08 3.19 4.07 4.50 4.70 5.80 5.30 5.35 5.77 5.55 5.64 5.67

3.84 4.16 4.16 4.32 3.53 4.01 4.01 4.16 3.37 3.84 3.53 4.47 4.32 4.01 4.16 3.53 4.79 4.32 4.32 3.84 3.84 3.84 3.84 3.69 4.63 4.16 6.66 5.88 6.03 6.66 6.66 6.97 6.19

3.08 3.50 3.65 3.01 2.69 2.83 2.76 2.74 2.55 2.76 2.39 2.98 2.84 2.47 2.54 2.37 3.29 3.68 3.26 2.32 2.06 2.11 2.29 3.05 3.52 3.67 4.86 4.37 4.45 4.77 4.60 4.75 4.76

3.41 3.88 3.73 3.88 3.09 3.73 3.57 3.88 3.09 3.73 3.09 4.19 3.57 3.41 3.88 3.09 4.35 3.57 4.19 3.73 3.57 3.57 3.41 3.09 4.04 3.88 5.91 4.98 5.44 5.91 5.76 5.91 5.29

2.76 3.17 3.19 2.67 2.47 2.57 2.51 2.52 2.40 2.54 2.24 2.70 2.53 2.26 2.23 2.18 2.97 3.24 2.82 2.12 1.92 1.96 2.24 2.75 3.06 3.26 4.20 3.78 3.82 4.09 3.97 4.14 4.19

2.33 2.49 2.33 2.64 2.17 2.64 2.49 2.49 2.33 2.64 2.33 2.49 2.49 2.33 2.49 2.33 2.64 2.17 2.64 2.49 2.33 2.49 2.33 2.17 2.33 2.81 2.81 2.81 2.96 2.96 3.12 3.12 2.96

2.10 2.16 2.10 2.18 2.02 2.15 2.09 2.08 2.03 2.17 2.00 2.08 2.01 1.93 2.01 1.89 2.16 2.07 2.17 1.93 1.83 1.87 1.90 2.01 2.00 2.14 2.22 2.26 2.31 2.36 2.42 2.50 2.50

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

03/01/05 03/02/05 03/03/05 03/04/05 03/05/05 03/06/05 03/07/05 03/08/05 03/09/05 03/10/05 03/11/05 03/12/05 03/13/05 03/14/05 03/15/05 03/16/05 03/17/05 03/18/05 03/19/05 03/20/05 03/21/05 03/22/05 03/23/05 03/24/05 03/25/05 03/26/05 03/27/05 03/28/05 03/29/05 03/30/05 03/31/05 04/01/05 04/02/05

9.43 9.58 10.83 11.60 11.44 11.76 12.07 12.84 13.00 13.77 13.31 12.53 11.14 11.14 10.67 10.05 11.14 10.05 10.21 11.91 11.76 11.29 11.91 12.07 11.14 10.36 10.05 12.22 11.44 10.21 11.76 10.98 13.46

8.59 8.79 9.57 10.06 10.04 10.21 10.54 11.14 11.42 12.09 11.85 11.41 9.96 9.52 9.52 9.04 9.22 9.00 9.36 10.35 10.91 10.71 10.82 10.80 10.17 9.19 9.57 10.65 10.50 9.31 9.68 9.95 10.94

9.03 8.26 10.43 10.43 10.58 10.89 11.20 11.97 12.28 12.74 12.74 12.12 10.58 10.58 10.12 8.88 11.20 9.34 9.34 10.89 11.51 11.20 11.04 11.36 10.43 9.49 9.64 10.89 10.89 9.96 11.97 10.89 14.13

7.48 7.40 8.29 8.52 8.56 8.86 9.22 9.67 10.08 10.66 10.50 10.23 8.92 8.40 8.49 8.21 8.73 8.02 8.51 9.35 10.00 9.89 9.65 9.37 8.72 8.05 9.00 9.72 9.51 8.53 9.12 9.71 11.01

9.33 8.57 10.11 10.73 10.88 10.73 11.04 11.50 11.81 12.12 12.12 12.12 10.58 10.58 10.73 9.96 11.19 9.96 10.11 11.04 11.81 10.73 10.58 10.73 10.58 10.58 10.58 12.27 10.88 10.88 12.27 11.34 13.66

7.76 7.82 8.47 8.73 8.94 9.04 9.40 9.78 10.12 10.46 10.38 10.30 9.17 8.90 9.23 8.98 9.33 8.75 9.24 9.65 10.37 10.01 9.62 9.39 8.98 8.89 9.76 10.40 9.91 9.27 9.94 10.21 11.25

7.46 7.00 8.39 8.86 9.01 9.17 9.48 10.09 10.25 10.72 10.72 10.25 9.48 9.17 9.32 8.08 9.32 8.39 8.08 9.48 10.41 9.17 8.54 9.01 8.86 9.01 8.86 10.25 9.32 9.48 10.72 10.41 12.73

207

5.72 5.88 6.45 6.90 6.90 7.01 7.33 7.74 7.95 8.40 8.45 8.20 7.24 6.77 7.17 6.93 7.38 6.82 7.13 7.87 8.57 8.15 7.55 7.59 7.20 7.13 7.98 8.82 8.32 7.73 8.22 8.75 9.92

6.82 6.19 7.44 8.06 8.21 8.21 8.67 9.29 9.45 9.92 9.92 9.61 8.37 8.37 8.52 7.13 8.67 7.74 7.44 8.67 9.76 8.21 7.59 8.21 8.21 8.21 7.74 9.76 8.98 8.83 10.38 9.61 12.40

4.74 4.95 5.53 5.97 5.97 6.07 6.39 6.79 6.97 7.42 7.45 7.26 6.25 5.92 6.25 5.88 6.44 5.87 6.14 7.04 7.67 7.21 6.62 6.78 6.39 6.31 7.07 8.05 7.53 6.94 7.28 7.96 9.14

6.07 5.44 6.68 6.84 6.99 6.99 7.30 7.92 7.92 8.38 8.38 8.38 7.46 7.46 7.46 6.22 8.22 6.53 6.53 8.07 8.53 6.99 6.84 7.76 7.46 7.61 6.84 8.99 8.22 8.69 8.53 8.84 11.62

4.11 4.39 4.78 5.11 5.16 5.28 5.52 5.83 6.02 6.40 6.44 6.39 5.48 5.35 5.60 5.26 5.76 5.27 5.51 6.28 6.88 6.43 5.95 6.14 5.91 5.81 6.54 7.23 6.88 6.55 6.55 7.23 8.34

3.28 3.28 3.44 3.59 3.59 3.75 3.91 4.07 4.22 4.22 4.38 4.38 4.38 4.38 4.38 4.07 4.69 4.38 4.38 4.54 4.85 4.69 4.85 5.17 5.01 5.32 5.01 5.63 5.17 5.48 5.95 5.95 6.26

2.65 2.64 2.77 2.90 2.97 3.02 3.13 3.27 3.41 3.54 3.65 3.66 3.68 3.69 3.71 3.72 4.00 3.87 4.00 4.21 4.34 4.46 4.51 4.54 4.53 4.67 4.93 5.04 4.85 5.03 5.20 5.41 5.68

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

04/03/05 04/04/05 04/05/05 04/06/05 04/07/05 04/08/05 04/09/05 04/10/05 04/11/05 04/12/05 04/13/05 04/14/05 04/15/05 04/16/05 04/17/05 04/18/05 04/19/05 04/20/05 04/21/05 04/22/05 04/23/05 04/24/05 04/25/05 04/26/05 04/27/05 04/28/05 04/29/05 04/30/05 05/01/05 05/02/05 05/03/05 05/04/05 05/05/05

13.31 12.69 13.16 14.39 13.92 12.53 12.22 13.16 13.62 14.23 13.62 11.91 13.16 14.54 14.39 13.31 12.22 11.91 12.38 14.08 15.49 14.70 16.44 17.72 17.88 18.37 16.76 17.40 18.04 18.53 19.51 18.69 18.21

12.34 11.85 11.28 12.34 12.40 11.64 11.43 11.10 12.37 13.21 11.54 10.34 11.33 12.63 13.61 12.08 11.29 11.13 11.24 12.30 14.29 13.09 13.89 15.87 16.70 16.43 14.99 14.88 15.74 16.71 17.48 17.13 16.89

12.43 11.97 12.59 14.76 13.52 13.82 13.52 14.13 14.29 13.67 11.51 12.12 13.52 15.07 13.21 13.36 13.06 10.89 11.04 14.92 13.06 12.12 16.02 17.93 18.73 16.97 14.92 15.87 17.13 16.34 18.09 16.34 16.65

11.65 10.68 10.09 11.85 12.47 11.97 11.63 11.16 12.01 12.17 10.38 9.60 10.34 11.84 12.07 10.53 10.34 9.70 9.81 11.50 12.29 11.16 12.58 14.62 15.32 14.24 12.74 12.62 13.67 13.95 14.85 14.30 14.04

12.42 11.66 12.42 14.43 13.50 13.19 13.19 13.50 12.58 11.81 10.88 10.58 11.50 12.58 11.81 10.27 10.27 9.33 10.11 12.27 11.34 9.96 12.42 13.19 12.89 11.81 10.88 12.27 12.73 12.42 13.04 11.81 11.81

11.53 10.60 10.15 11.94 12.58 11.84 11.47 11.02 11.14 10.55 9.39 8.66 9.23 10.16 10.12 9.01 9.08 8.27 8.78 9.81 10.05 9.10 10.29 10.90 11.17 10.38 9.47 9.94 10.40 10.57 10.90 10.23 10.42

11.96 10.25 11.18 13.66 13.19 11.80 11.33 12.42 11.64 11.49 9.79 9.63 10.87 11.80 10.41 9.63 9.32 8.24 9.79 11.64 10.25 8.86 11.64 12.57 12.27 10.87 10.41 11.64 11.80 11.64 12.11 10.41 11.18

208

10.17 9.10 8.80 10.77 11.44 10.61 10.12 9.86 9.95 9.52 8.44 7.71 8.30 9.19 8.99 8.13 8.11 7.48 8.12 9.03 9.07 8.24 9.41 9.87 9.98 9.27 8.65 9.06 9.45 9.55 9.83 9.12 9.49

10.69 9.45 11.01 13.64 12.24 11.62 10.69 12.24 10.69 11.01 9.29 9.14 10.38 11.31 9.45 9.29 8.83 7.74 9.61 11.16 9.45 8.37 11.01 11.78 11.62 10.54 10.07 11.01 11.31 11.47 11.47 9.92 10.69

9.23 8.21 8.05 10.05 10.62 9.90 9.37 9.27 9.27 8.88 7.95 7.22 7.76 8.66 8.41 7.72 7.55 7.06 7.74 8.49 8.48 7.75 8.73 9.07 9.15 8.56 8.13 8.48 8.81 8.89 9.13 8.42 8.91

8.99 8.99 10.23 12.39 10.85 11.32 9.77 11.78 10.23 9.92 8.84 8.53 9.31 10.39 8.22 9.15 8.22 7.30 9.15 10.08 8.84 8.07 10.08 10.54 10.39 9.61 9.31 10.08 10.54 10.08 10.39 8.99 9.92

8.39 7.43 7.56 9.37 9.67 9.28 8.71 8.83 8.56 8.05 7.37 6.85 7.25 8.02 7.81 7.44 7.03 6.69 7.32 7.89 7.84 7.28 8.03 8.27 8.28 7.83 7.65 7.91 8.19 8.09 8.34 7.80 8.21

6.11 5.95 6.26 7.35 7.04 6.88 6.57 6.73 6.57 6.73 6.26 6.57 6.88 7.19 6.73 6.57 6.57 6.57 6.73 7.04 7.04 6.88 6.88 6.88 7.04 6.88 7.04 7.19 7.04 7.19 7.19 7.19 7.19

5.66 5.64 5.58 6.25 6.46 6.30 6.09 6.03 6.04 6.33 5.98 6.05 6.28 6.68 6.52 6.26 6.31 6.30 6.39 6.65 6.69 6.57 6.63 6.61 6.70 6.67 6.77 6.84 6.85 6.92 6.92 7.00 7.09

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

05/06/05 05/07/05 05/08/05 05/09/05 05/10/05 05/11/05 05/12/05 05/13/05 05/14/05 05/15/05 05/16/05 05/17/05 05/18/05 05/19/05 05/20/05 05/21/05 05/22/05 05/23/05 05/24/05 05/25/05 05/26/05 05/27/05 05/28/05 05/29/05 05/30/05 05/31/05 06/01/05 06/02/05 06/03/05 06/04/05 06/05/05 06/06/05 06/07/05

17.40 16.61 16.28 15.65 13.46 13.92 16.76 18.21 19.02 17.88 16.13 14.54 15.49 18.21 17.24 17.40 18.86 18.37 18.69 19.51 20.97 22.13 23.13 22.13 21.97 20.97 19.18 19.34 20.31 21.63 20.64 18.37 17.40

16.26 14.89 15.49 14.46 12.65 12.67 14.11 16.35 17.28 16.79 14.69 13.12 14.45 16.23 16.29 15.34 16.76 16.46 16.69 17.08 18.12 19.37 20.59 19.93 19.23 19.39 17.71 17.20 17.73 19.04 18.56 16.90 15.81

15.55 14.92 14.60 13.36 12.12 11.82 15.87 17.13 16.97 15.07 13.36 14.29 15.87 17.77 15.71 16.65 18.25 17.61 17.29 18.09 19.38 20.68 21.67 19.87 20.84 18.25 18.09 17.77 18.89 20.19 18.25 17.45 15.87

13.71 12.84 12.98 12.36 11.05 10.81 12.83 14.40 14.83 14.16 12.24 12.11 13.79 15.34 14.51 14.04 15.62 15.39 15.23 15.37 16.30 17.59 18.49 17.65 17.49 16.80 15.72 15.43 16.20 17.24 16.73 15.39 14.21

11.19 11.66 12.27 11.19 10.11 10.42 12.58 13.50 13.50 12.73 11.04 12.58 12.89 13.66 12.58 14.12 15.22 14.58 14.58 15.06 15.84 16.16 16.01 14.90 16.01 14.90 14.27 14.58 15.22 16.01 14.90 14.43 13.50

10.15 10.12 10.57 9.88 9.32 9.24 10.54 11.24 11.41 10.90 10.11 10.51 11.32 12.20 11.58 11.89 12.85 12.73 12.51 12.73 13.39 13.87 13.85 13.33 13.55 13.01 12.77 12.54 13.07 13.68 13.07 12.66 11.95

10.41 10.72 11.49 9.94 9.48 9.79 12.11 13.04 12.88 11.33 9.94 11.96 12.27 13.04 11.49 13.19 14.59 13.81 13.81 14.28 14.91 15.07 15.22 14.12 15.22 13.19 13.19 13.81 14.43 15.22 13.35 13.66 12.73

209

9.20 9.18 9.58 9.05 8.62 8.60 9.84 10.42 10.57 9.94 9.39 9.90 10.42 11.18 10.46 10.85 11.74 11.55 11.36 11.56 12.17 12.47 12.55 12.14 12.40 11.79 11.69 11.52 12.01 12.54 11.88 11.73 11.08

9.76 10.38 11.01 9.61 9.14 9.29 11.62 12.40 12.40 10.23 9.29 11.62 11.62 12.09 10.85 12.71 13.95 13.33 13.49 13.79 14.42 14.26 14.42 13.64 14.57 12.71 12.56 13.49 13.95 14.73 12.56 13.33 12.40

8.58 8.62 8.93 8.51 8.15 8.14 9.36 9.79 9.93 9.27 8.83 9.39 9.73 10.39 9.77 10.20 11.00 10.81 10.66 10.88 11.37 11.57 11.63 11.28 11.61 11.07 11.00 10.97 11.41 11.83 11.17 11.16 10.57

9.15 9.61 10.39 8.99 8.84 8.84 10.70 11.16 11.32 9.46 8.53 11.01 10.39 11.01 10.23 11.62 12.71 12.24 12.24 12.55 13.02 12.86 13.17 12.71 13.17 11.78 11.93 12.55 13.02 13.48 12.08 12.71 11.78

7.97 8.09 8.31 8.00 7.79 7.79 8.79 9.00 9.17 8.64 8.25 8.92 9.05 9.52 9.16 9.54 10.14 9.94 9.91 10.11 10.46 10.57 10.60 10.32 10.75 10.27 10.27 10.37 10.71 10.98 10.47 10.56 10.16

7.19 7.19 7.50 7.66 7.35 7.50 7.81 7.81 7.97 7.81 7.97 8.12 8.12 8.43 8.43 8.58 8.58 8.74 8.89 9.05 9.05 9.05 9.21 9.21 9.36 9.36 9.36 9.52 9.67 9.67 9.67 9.67 9.67

7.07 7.08 7.21 7.32 7.29 7.29 7.51 7.65 7.75 7.77 7.72 7.91 8.06 8.13 8.18 8.31 8.42 8.54 8.59 8.73 8.82 8.86 8.93 9.02 9.08 9.12 9.18 9.26 9.35 9.38 9.45 9.44 9.52

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

06/08/05 06/09/05 06/10/05 06/11/05 06/12/05 06/13/05 06/14/05 06/15/05 06/16/05 06/17/05 06/18/05 06/19/05 06/20/05 06/21/05 06/22/05 06/23/05 06/24/05 06/25/05 06/26/05 06/27/05 06/28/05 06/29/05 06/30/05 07/01/05 07/02/05 07/03/05 07/04/05 07/05/05 07/06/05 07/07/05 07/08/05 07/09/05 07/10/05

18.21 19.67 19.51 20.47 19.99 20.64 20.97 22.13 21.47 19.99 19.51 20.97 23.13 23.64 24.34 23.31 24.17 23.99 22.63 21.13 20.15 21.80 22.80 23.82 22.63 22.30 22.97 23.82 24.68 25.21 25.91 24.34 21.30

15.93 17.15 17.98 18.43 18.09 17.88 18.98 19.24 19.93 18.83 18.11 18.29 20.10 21.52 21.94 21.13 21.57 22.10 20.89 19.23 18.37 19.48 20.62 21.46 21.16 20.52 20.73 21.41 22.32 22.94 23.59 20.60 18.89

16.65 18.09 18.73 19.71 18.09 19.06 18.09 20.03 19.54 17.93 17.13 19.54 20.84 20.51 20.68 20.19 20.35 20.03 19.54 17.29 18.09 19.38 19.87 20.35 20.03 19.71 19.87 20.35 21.17 22.00 22.16 20.03 18.89

14.39 15.38 16.44 16.93 16.18 16.06 16.59 17.08 17.63 16.56 15.81 16.57 18.20 18.92 18.66 18.15 18.14 18.30 17.72 16.43 16.41 17.32 18.09 18.68 18.50 17.98 18.06 18.60 19.24 19.58 19.81 17.52 16.85

14.43 15.37 15.53 15.22 14.90 15.69 15.22 16.16 15.22 15.06 15.53 16.63 17.11 16.32 17.11 16.79 16.94 17.11 16.32 15.06 15.69 16.94 17.58 17.74 17.11 17.11 17.58 17.74 17.91 18.07 18.23 16.94 16.94

12.41 12.94 13.44 13.44 13.02 13.12 13.56 13.82 13.58 13.64 13.55 13.88 14.62 14.55 14.60 14.50 14.54 14.86 14.43 13.49 14.11 14.68 15.08 15.49 15.17 14.91 15.18 15.47 15.73 15.92 16.06 14.63 14.92

13.66 14.91 14.75 14.43 14.28 15.07 14.59 15.54 14.28 14.28 14.75 16.02 16.33 15.54 16.33 16.02 16.33 16.49 15.86 13.66 15.07 16.33 16.81 16.97 16.49 16.65 16.97 17.13 17.13 17.44 17.44 15.38 16.18

210

11.54 12.06 12.41 12.40 12.11 12.29 12.62 12.92 12.59 12.76 12.68 13.07 13.62 13.55 13.69 13.60 13.66 13.94 13.56 12.72 13.37 13.83 14.26 14.55 14.27 14.12 14.38 14.61 14.82 15.00 15.12 13.80 14.27

13.18 14.26 14.26 13.79 13.79 14.57 14.26 14.89 13.79 13.95 14.26 15.37 15.68 15.21 15.68 15.53 15.68 15.84 15.53 13.33 14.42 15.84 16.32 16.48 16.00 16.16 16.48 16.63 16.63 16.95 16.95 14.42 16.00

11.05 11.50 11.74 11.72 11.53 11.73 12.00 12.27 11.95 12.18 12.10 12.52 12.92 12.88 13.03 12.99 13.08 13.30 13.00 12.33 12.91 13.32 13.69 13.94 13.70 13.60 13.85 14.01 14.19 14.37 14.48 13.36 13.87

12.55 13.32 13.17 12.71 12.86 13.48 13.17 13.63 13.02 13.17 13.02 14.25 14.41 14.25 14.56 14.41 14.56 14.72 14.41 12.39 13.94 14.87 15.19 15.19 15.03 15.19 15.35 15.51 15.51 15.67 15.67 13.63 15.03

10.51 10.87 10.98 10.97 10.93 11.12 11.31 11.50 11.29 11.48 11.43 11.85 12.07 12.10 12.28 12.26 12.39 12.53 12.38 11.90 12.41 12.74 13.02 13.18 13.00 12.99 13.20 13.32 13.44 13.61 13.72 12.93 13.39

9.83 9.83 9.98 9.98 10.14 10.14 10.29 10.29 10.45 10.61 10.61 10.92 10.92 11.07 11.22 11.22 11.38 11.53 11.53 11.53 11.69 11.84 12.00 12.00 12.16 12.16 12.31 12.31 12.31 12.47 12.62 12.47 12.62

9.61 9.63 9.67 9.83 9.90 9.99 10.08 10.13 10.27 10.39 10.45 10.62 10.73 10.85 10.98 11.04 11.21 11.29 11.39 11.49 11.53 11.67 11.79 11.82 11.85 11.99 12.04 12.13 12.19 12.29 12.40 12.37 12.52

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

07/11/05 07/12/05 07/13/05 07/14/05 07/15/05 07/16/05 07/17/05 07/18/05 07/19/05 07/20/05 07/21/05 07/22/05 07/23/05 07/24/05 07/25/05 07/26/05 07/27/05 07/28/05 07/29/05 07/30/05 07/31/05 08/01/05 08/02/05 08/03/05 08/04/05 08/05/05 08/06/05 08/07/05 08/08/05 08/09/05 08/10/05 08/11/05 08/12/05

23.48 25.03 24.86 23.64 24.34 24.68 23.82 23.99 25.03 25.38 25.21 25.73 25.03 24.51 23.13 23.31 23.99 23.82 24.51 25.21 25.21 25.38 23.99 23.31 23.82 24.34 24.34 23.64 23.48 24.34 24.17 23.13 22.47

20.74 22.57 23.16 21.74 22.03 22.71 21.62 21.77 22.71 23.27 23.47 24.16 22.98 22.67 21.57 21.01 21.59 22.00 22.62 23.03 23.26 23.58 22.58 21.68 21.83 22.32 22.70 22.67 22.21 22.40 22.60 21.60 21.15

21.67 22.00 22.00 20.51 21.67 22.49 21.50 21.67 22.33 22.33 22.33 23.33 22.16 22.00 21.50 21.67 22.33 23.16 22.66 23.33 23.67 22.66 21.50 21.33 21.67 22.00 21.67 20.51 21.50 22.16 21.83 20.68 19.87

18.67 19.49 19.92 18.87 19.15 20.06 19.02 19.05 19.78 19.95 20.04 20.71 19.99 19.56 19.31 18.96 19.33 19.68 19.98 20.56 20.87 20.80 20.04 19.34 19.47 19.85 19.87 19.61 19.77 20.36 20.20 19.29 18.75

18.23 18.71 18.39 18.23 18.71 18.71 18.23 18.71 19.03 19.03 19.03 19.68 19.03 19.19 18.55 19.03 19.19 18.87 19.19 19.68 19.68 18.87 18.71 19.36 19.52 19.68 19.52 18.71 19.68 20.00 19.84 19.52 19.19

15.72 16.22 16.35 15.92 16.22 16.53 16.08 16.28 16.62 16.77 16.88 17.44 17.03 16.92 16.69 16.65 16.97 16.85 17.46 17.61 17.70 17.51 17.22 17.17 17.34 17.53 17.56 17.43 17.80 18.05 17.97 17.61 17.47

17.44 17.92 17.76 17.61 17.92 17.92 17.76 18.08 18.24 18.24 18.24 18.57 18.41 18.57 17.92 18.41 18.57 18.24 18.57 19.06 19.22 18.08 18.24 18.73 19.06 19.22 18.73 18.24 19.06 19.38 19.22 19.06 18.89

211

14.94 15.33 15.44 15.09 15.38 15.61 15.29 15.47 15.76 15.88 15.96 16.46 16.09 16.05 15.83 15.89 16.18 16.06 16.61 16.76 16.88 16.61 16.50 16.50 16.63 16.85 16.86 16.75 17.16 17.32 17.25 16.96 16.87

16.95 17.27 17.27 17.11 17.43 17.43 17.27 17.59 17.75 17.91 17.59 18.07 17.91 18.07 17.59 18.07 18.23 17.91 18.23 18.72 18.72 17.27 17.91 18.56 18.72 18.88 18.23 17.91 18.72 19.04 18.88 18.72 18.56

14.44 14.75 14.82 14.57 14.84 15.02 14.79 14.98 15.22 15.32 15.36 15.79 15.52 15.53 15.31 15.47 15.70 15.59 16.10 16.22 16.35 16.05 16.11 16.17 16.29 16.47 16.49 16.39 16.83 16.92 16.91 16.69 16.65

15.82 16.14 16.14 15.98 16.36 16.46 16.29 16.61 16.77 16.93 16.83 16.93 17.08 17.24 16.77 17.24 17.24 17.08 17.63 17.63 17.79 16.83 17.47 17.79 17.88 18.04 17.56 17.08 18.04 18.20 18.20 18.04 18.04

13.79 14.03 14.10 13.95 14.19 14.35 14.21 14.38 14.56 14.67 14.73 15.06 14.91 14.93 14.76 14.98 15.12 15.05 15.50 15.62 15.73 15.52 15.62 15.71 15.79 15.93 15.97 15.92 16.34 16.38 16.41 16.29 16.28

12.78 12.93 12.93 13.09 13.24 13.24 13.40 13.40 13.56 13.56 13.71 13.71 13.86 14.02 14.02 14.17 14.17 14.33 14.48 14.64 14.64 14.64 14.80 14.96 14.96 15.12 15.28 15.44 15.44 15.59 15.59 15.76 15.91

12.63 12.71 12.81 12.93 13.01 13.06 13.18 13.30 13.35 13.45 13.55 13.62 13.74 13.80 13.83 14.03 14.07 14.16 14.26 14.38 14.45 14.56 14.70 14.75 14.87 15.02 15.12 15.24 15.36 15.43 15.53 15.65 15.70

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

08/13/05 08/14/05 08/15/05 08/16/05 08/17/05 08/18/05 08/19/05 08/20/05 08/21/05 08/22/05 08/23/05 08/24/05 08/25/05 08/26/05 08/27/05 08/28/05 08/29/05 08/30/05 08/31/05 09/01/05 09/02/05 09/03/05 09/04/05 09/05/05 09/06/05 09/07/05 09/08/05 09/09/05 09/10/05 09/11/05 09/12/05 09/13/05 09/14/05

21.47 21.30 21.47 22.13 21.80 22.13 21.97 22.80 22.80 23.64 22.80 21.13 20.47 20.97 21.63 21.80 21.30 19.83 19.99 20.47 20.64 21.13 20.47 19.99 20.15 20.64 20.64 19.99 18.04 17.56 17.24 18.37 18.37

20.17 19.93 20.04 20.63 20.56 20.57 20.57 20.88 21.30 22.04 21.52 19.67 18.98 19.29 19.97 20.24 20.12 18.44 18.20 18.68 19.10 19.55 19.44 18.68 18.67 18.96 19.17 18.63 16.92 16.23 15.98 16.87 16.89

19.87 20.03 20.19 20.35 20.35 20.68 20.68 21.33 21.33 22.00 21.17 19.87 19.71 20.35 20.68 20.68 20.51 19.38 19.71 20.68 21.01 20.92 22.08 22.58 22.75 23.59 25.67 23.77 16.88 17.04 19.29 20.92 20.92

18.60 18.60 18.71 19.14 19.08 19.32 19.08 19.51 19.73 20.57 19.81 18.42 17.99 18.52 19.09 19.26 19.29 17.78 17.66 18.33 18.73 18.63 16.91 17.17 16.82 17.42 18.38 17.09 13.04 12.17 13.35 15.97 14.78

19.36 19.52 19.84 19.36 19.68 19.84 20.00 20.32 20.48 20.64 20.16 19.36 19.84 20.32 20.32 20.64 20.16 19.36 20.00 20.32 20.32 20.64 19.68 19.84 20.32 20.48 20.64 20.16 19.03 18.87 18.87 19.36 19.36

17.42 17.53 17.72 17.80 18.07 18.23 18.07 18.42 18.55 19.03 18.58 17.81 17.87 18.34 18.62 18.67 18.72 17.84 18.10 18.59 18.75 18.92 18.50 18.34 18.58 18.86 19.04 18.82 17.69 17.44 17.48 18.07 17.82

18.89 19.22 19.38 18.89 19.38 19.55 19.71 20.03 20.03 20.19 19.87 19.22 19.55 19.87 20.03 20.36 20.03 19.22 19.87 20.19 20.19 20.36 19.38 19.87 20.19 20.36 20.52 19.71 19.06 19.06 18.89 19.38 19.38

212

16.86 17.00 17.18 17.21 17.51 17.68 17.55 17.87 17.99 18.40 18.00 17.38 17.50 17.89 18.11 18.20 18.21 17.44 17.74 18.19 18.30 18.45 18.06 18.02 18.23 18.43 18.61 18.33 17.48 17.28 17.30 17.83 17.56

18.72 19.04 19.21 18.72 19.21 19.37 19.54 19.86 19.86 20.03 19.54 19.21 19.54 19.86 19.86 20.19 19.86 19.37 19.86 20.35 20.35 20.35 19.37 19.86 20.35 20.51 20.67 19.86 19.37 19.37 19.21 19.54 19.54

16.67 16.84 17.00 16.98 17.25 17.45 17.37 17.63 17.75 18.08 17.78 17.30 17.44 17.78 17.95 18.05 18.03 17.42 17.73 18.11 18.20 18.32 17.93 18.01 18.20 18.37 18.52 18.20 17.59 17.43 17.46 17.88 17.61

18.20 18.36 18.52 18.36 18.52 18.68 18.84 19.17 19.24 19.24 19.08 18.92 19.24 19.40 19.40 19.56 19.40 19.08 19.56 19.89 19.82 19.98 19.17 19.66 19.98 19.98 20.14 19.49 19.33 19.33 19.17 19.49 19.33

16.37 16.51 16.63 16.66 16.87 17.05 17.01 17.21 17.30 17.61 17.44 17.14 17.31 17.56 17.67 17.75 17.74 17.38 17.68 17.92 17.94 18.05 17.77 17.93 18.08 18.16 18.28 17.96 17.70 17.58 17.58 17.85 17.62

15.91 16.07 16.23 16.39 16.39 16.39 16.54 16.71 16.86 16.86 17.02 17.02 17.18 17.34 17.34 17.50 17.50 17.50 17.66 17.66 17.82 17.66 17.66 17.82 17.98 17.98 18.14 17.98 17.98 17.98 17.82 17.82 17.82

15.87 15.96 16.03 16.11 16.24 16.29 16.41 16.50 16.58 16.70 16.80 16.86 16.96 17.06 17.12 17.22 17.26 17.31 17.42 17.47 17.53 17.56 17.59 17.68 17.77 17.80 17.85 17.79 17.84 17.84 17.73 17.71 17.57

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

09/15/05 09/16/05 09/17/05 09/18/05 09/19/05 09/20/05 09/21/05 09/22/05 09/23/05 09/24/05 09/25/05 09/26/05 09/27/05 09/28/05 09/29/05 09/30/05 10/01/05 10/02/05 10/03/05 10/04/05 10/05/05 10/06/05 10/07/05 10/08/05 10/09/05 10/10/05 10/11/05 10/12/05 10/13/05 10/14/05 10/15/05 10/16/05 10/17/05

18.53 17.88 17.56 17.56 17.56 17.72 18.37 17.40 16.61 15.65 15.02 14.54 16.61 16.61 16.13 17.08 16.61 14.86 14.54 14.08 13.62 13.62 14.08 15.33 15.33 14.54 13.77 13.77 14.54 14.86 15.02 14.70 14.70

16.99 17.03 16.67 16.27 16.22 16.51 17.08 16.38 15.89 14.61 13.80 13.74 14.85 15.40 14.96 15.59 15.34 13.99 13.88 13.28 12.52 12.45 12.93 14.13 14.20 13.46 12.89 12.75 13.20 13.70 14.21 13.67 13.65

22.08 21.42 14.98 17.52 20.42 22.58 22.92 21.25 19.62 12.03 17.36 18.32 22.25 21.42 22.42 24.63 16.72 13.11 13.73 12.81 14.19 18.16 18.97 19.13 18.81 18.16 13.58 16.41 21.08 25.33 22.58 21.25 21.58

15.62 15.25 13.36 13.01 13.88 15.77 16.97 15.13 14.17 10.50 10.76 12.39 14.73 14.06 13.28 16.23 12.87 9.92 9.97 8.74 8.58 10.34 12.05 13.49 12.37 10.70 9.73 10.79 12.64 15.36 15.91 12.60 12.99

19.36 18.87 18.23 18.71 19.03 19.19 19.19 18.39 18.23 16.94 17.42 17.58 18.07 17.58 17.58 18.23 17.74 16.32 15.84 15.37 15.22 15.53 15.53 16.63 16.16 15.37 14.74 14.90 15.53 16.01 16.01 15.06 15.53

17.97 17.83 17.43 17.30 17.46 17.81 18.18 17.39 17.26 15.65 15.57 16.27 17.01 16.47 16.30 16.93 16.28 15.28 15.23 14.65 14.18 14.31 14.62 15.48 15.00 14.36 13.87 13.62 14.27 14.77 15.20 13.90 14.25

19.38 19.06 17.92 18.73 19.06 19.22 18.89 18.41 17.92 16.49 17.44 17.61 17.92 17.76 17.61 17.92 17.13 16.02 15.54 15.38 15.07 15.38 15.54 16.02 15.70 14.75 14.28 14.12 14.91 15.22 15.22 14.12 14.75

213

17.70 17.55 17.12 17.09 17.19 17.49 17.73 17.02 16.92 15.34 15.53 16.02 16.67 16.16 15.95 16.46 15.67 14.89 14.81 14.30 13.87 14.07 14.28 15.00 14.45 13.70 13.02 12.91 13.62 14.09 14.42 13.17 13.57

19.54 19.21 18.23 19.04 19.21 19.37 19.04 18.39 18.07 16.16 17.75 17.59 17.91 17.91 17.75 17.91 16.95 16.32 15.68 15.53 15.37 15.68 15.53 15.68 15.53 14.89 13.49 14.26 15.05 15.21 14.42 14.11 14.73

17.71 17.55 17.17 17.18 17.21 17.45 17.60 16.96 16.85 15.42 15.76 16.05 16.59 16.14 15.92 16.31 15.53 14.96 14.83 14.33 13.93 14.12 14.19 14.64 14.12 13.35 12.50 12.59 13.30 13.73 13.93 12.83 13.23

19.33 19.01 18.20 18.84 19.01 19.17 18.84 18.36 18.04 15.98 17.88 17.72 17.88 17.88 17.72 17.72 16.46 16.61 16.14 15.67 15.51 15.67 15.67 16.14 15.82 15.03 13.17 14.25 15.03 15.35 14.41 14.41 14.56

17.65 17.48 17.24 17.22 17.21 17.33 17.38 16.89 16.80 15.69 16.10 16.14 16.50 16.16 15.95 16.15 15.44 15.19 14.98 14.58 14.22 14.31 14.24 14.52 14.13 13.31 12.48 12.62 13.30 13.58 13.60 12.86 13.13

17.66 17.66 17.50 17.34 17.34 17.34 17.18 17.02 16.86 16.54 16.54 16.54 16.39 16.23 16.23 16.07 15.91 15.76 15.59 15.28 15.12 14.96 14.96 14.48 14.33 13.71 13.71 14.02 13.71 13.71 13.71 13.40 13.09

17.56 17.49 17.35 17.23 17.16 17.15 17.00 16.89 16.69 16.54 16.44 16.34 16.27 16.12 15.97 15.92 15.79 15.58 15.42 15.18 14.96 14.77 14.59 14.01 13.64 13.20 13.43 13.56 13.18 13.27 13.44 12.95 12.68

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

10/18/05 10/19/05 10/20/05 10/21/05 10/22/05 10/23/05 10/24/05 10/25/05 10/26/05 10/27/05 10/28/05 10/29/05 10/30/05 10/31/05 11/01/05 11/02/05 11/03/05 11/04/05 11/05/05 11/06/05 11/07/05 11/08/05 11/09/05 11/10/05 11/11/05 11/12/05 11/13/05 11/14/05 11/15/05 11/16/05 11/17/05 11/18/05 11/19/05

14.23 14.39 14.54 13.92 13.31 13.00 13.00 13.46 13.46 13.00 13.31 12.69 11.76 11.29 11.60 11.29 10.83 10.67 10.21 10.36 10.83 10.52 9.27 9.27 9.43 9.74 8.96 8.96 7.73 7.27 7.42 7.27 7.73

13.41 13.55 13.54 13.08 12.50 12.18 12.15 12.53 12.95 12.60 12.45 12.08 11.05 10.70 10.89 11.22 10.42 10.23 9.73 9.83 10.52 9.83 8.65 8.48 8.75 9.02 8.56 8.35 7.16 6.55 6.60 6.65 6.92

22.92 23.94 25.50 22.42 22.92 26.37 25.84 27.08 20.75 12.65 16.41 17.04 20.26 15.77 16.09 10.94 11.10 9.39 7.39 9.55 10.33 15.14 12.65 10.94 9.39 18.48 5.68 13.73 13.73 13.58 19.94 11.10 14.35

13.08 13.54 13.56 11.52 11.36 11.74 12.44 12.93 12.36 9.43 10.51 9.96 8.62 9.59 11.55 8.99 6.78 6.87 5.28 7.85 7.89 6.60 4.65 4.18 4.96 6.94 4.52 5.50 3.23 3.26 4.98 3.64 4.49

15.22 15.22 15.06 14.43 14.58 14.43 14.58 14.90 14.74 14.12 14.27 13.96 13.04 12.89 12.12 12.89 12.12 12.58 12.27 12.27 12.89 11.96 11.04 11.19 11.81 11.81 10.88 10.73 9.49 9.33 9.80 9.80 10.42

14.30 14.40 14.05 13.61 13.47 13.32 13.49 13.92 14.18 13.27 13.17 13.01 12.04 11.97 11.45 11.82 11.52 11.77 11.31 11.55 11.90 10.93 10.21 10.38 10.75 10.83 10.24 10.04 8.58 8.49 8.78 8.79 9.01

14.59 14.28 14.28 13.81 13.66 13.66 13.66 14.12 13.81 13.19 13.19 12.73 11.96 11.64 11.49 11.33 11.03 11.03 10.56 10.56 11.03 10.41 9.94 10.09 10.25 10.09 9.01 9.01 7.77 8.08 8.24 8.24 8.54

214

13.59 13.57 13.29 12.87 12.71 12.56 12.64 13.04 13.20 12.31 12.22 12.06 11.03 10.87 10.91 11.04 10.48 10.41 9.97 10.08 10.43 9.44 8.75 9.00 9.30 9.35 8.44 8.34 6.87 6.94 7.21 7.24 7.39

14.57 13.95 14.11 13.79 13.64 13.64 13.49 13.79 13.18 12.56 12.71 12.40 11.47 11.16 11.31 11.30 10.99 10.84 10.37 10.37 10.84 10.06 9.90 10.22 10.22 10.06 8.51 8.97 7.58 8.04 8.20 8.20 8.35

13.22 13.10 12.88 12.50 12.37 12.19 12.23 12.53 12.62 11.79 11.71 11.58 10.55 10.32 10.75 10.86 10.40 10.36 9.91 9.97 10.34 9.29 8.71 8.99 9.21 9.23 8.21 8.19 6.75 6.92 7.17 7.15 7.31

14.56 13.79 14.09 13.94 13.79 13.63 13.63 13.79 13.48 12.24 13.02 12.86 12.08 11.01 11.32 11.16 10.85 10.85 10.39 9.92 10.54 9.77 9.92 10.08 9.92 9.92 8.22 8.69 7.92 8.38 8.38 8.07 8.38

13.07 12.93 12.76 12.47 12.35 12.16 12.20 12.37 12.45 11.84 11.72 11.64 10.68 10.40 10.73 10.64 10.14 10.26 9.71 9.71 10.01 9.03 8.62 8.96 9.12 8.95 7.88 7.96 6.78 7.12 7.24 7.14 7.23

13.56 13.40 13.40 13.24 13.09 13.32 13.16 13.16 12.70 12.23 12.54 12.39 12.23

12.98 12.99 12.96 12.74 12.59 12.60 12.45 12.46 12.28 12.10 11.96 11.90 11.69

11.46 11.62 11.31 11.16 11.00 10.84 10.69 10.69 10.53 10.38 9.59 9.59 9.75 9.59 9.44 9.29 8.98 8.83

11.38 11.36 11.05 10.87 10.91 10.81 10.49 10.34 10.23 10.01 9.37 9.50 9.45 9.16 9.10 8.89 8.72 8.35

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

11/20/05 11/21/05 11/22/05 11/23/05 11/24/05 11/25/05 11/26/05 11/27/05 11/28/05 11/29/05 11/30/05 12/01/05 12/02/05 12/03/05 12/04/05 12/05/05 12/06/05 12/07/05 12/08/05 12/09/05 12/10/05 12/11/05 12/12/05 12/13/05 12/14/05 12/15/05 12/16/05 12/17/05 12/18/05 12/19/05 12/20/05 12/21/05 12/22/05

7.42 6.80 6.49 6.18 5.86 5.86 6.49 5.71 5.08 4.93 5.55 5.24 6.02 6.02 5.55 4.62 4.46 4.46 2.26 1.94 2.89 2.42 2.42 3.05 2.57 2.26 1.78 2.57 1.78 2.73 4.77 5.71 5.71

6.85 6.33 6.28 6.09 5.78 5.67 6.00 5.18 4.64 4.70 4.88 4.77 5.43 5.70 5.05 4.13 3.91 3.58 1.70 1.43 2.39 2.17 2.00 2.46 2.00 1.72 1.58 2.06 1.16 1.58 3.83 5.22 5.47

16.57 16.24 2.24 1.61 0.65 2.24 12.03 15.14 3.66 3.18 8.47 3.66 11.26 14.66 16.57 10.64 2.08 1.13 8.93 2.87 2.56 4.59 0.81 12.34 5.22 7.23 -3.77 1.13 -2.59 0.01 0.81 2.87 4.12

4.47 2.69 0.32 0.47 -0.44 0.58 3.56 2.31 -0.20 1.56 1.77 1.85 3.07 2.74 2.37 -0.54 -1.11 -3.28 -2.39 -3.57 -2.82 -2.70 -4.03 -0.41 -3.16 -2.89 -4.45 -3.70 -4.37 -1.17 -0.01 1.25 2.29

10.11 9.80 9.18 9.18 8.72 8.42 8.88 7.65 7.34 7.65 7.81 8.57 8.72 8.42 7.65 7.19 6.88 6.42 4.87 5.02 5.96 5.80 5.18 5.49 5.18 4.40 4.56 5.49 4.71 5.33 6.42 7.03 7.50

8.87 8.79 8.50 8.53 7.83 7.55 7.50 6.71 6.39 7.01 6.92 7.42 7.93 7.49 6.48 6.07 6.01 5.21 3.88 4.00 4.76 4.48 4.25 4.52 4.24 3.60 3.76 4.10 3.39 4.35 5.51 6.36 6.63

8.24 8.08 7.77 7.46 6.84 6.22 7.00 5.76 5.29 5.76 6.07 7.00 6.84 6.38 5.44 4.82 4.98 4.35 2.77 3.09 3.72 3.09 2.77 3.41 2.77 2.29 1.98 2.77 1.98 2.93 4.04 4.35 5.44

215

7.25 7.06 6.85 6.94 6.24 5.86 5.90 4.97 4.44 5.13 5.28 5.87 6.33 5.83 4.68 4.09 4.16 3.39 1.89 2.18 2.89 2.39 2.09 2.49 2.05 1.72 1.59 2.02 1.21 1.90 3.38 3.99 4.63

8.04 8.04 7.58 7.11 6.49 6.02 6.64 5.39 5.08 5.39 5.86 6.03 6.03 5.41 4.63 4.16 4.16 3.37 1.79 2.27 2.90 2.42 2.11 2.58 1.94 1.47 1.31 2.11 0.83 1.94 3.22 3.53 4.63

7.12 6.96 6.78 6.80 6.13 5.73 5.79 4.82 4.29 4.84 5.12 5.44 5.63 5.10 3.98 3.36 3.43 2.60 1.12 1.50 2.15 1.66 1.34 1.70 1.27 0.93 0.84 1.30 0.38 0.99 2.52 3.09 3.92

8.07 8.07 7.76 6.99 6.37 5.76 6.53 5.60 5.29 5.29 6.07 5.91 6.68 5.60 5.13 4.51 4.51 3.57 2.78 3.09 3.26 3.09 2.94 2.94 2.62 2.31 1.83 2.62 1.04 1.83 3.09 3.26 4.19

6.98 6.91 6.76 6.71 6.14 5.64 5.68 4.80 4.40 4.69 5.09 5.39 5.76 5.28 4.33 3.82 3.94 2.96 1.87 2.23 2.62 2.20 1.94 2.18 1.76 1.48 1.43 1.75 0.79 1.17 2.46 2.89 3.77

8.83 8.52 8.37 8.06 7.75 7.75 7.59 7.44 7.13 6.98 6.98 6.67 6.67 6.51 6.36 6.04 5.89 5.58 5.27 5.11 4.80 4.64 4.33 4.17 4.02 3.71 3.55 3.55 2.76 2.44 2.44 2.60 2.76

8.33 8.23 8.09 7.88 7.50 7.46 7.37 7.15 6.90 6.81 6.71 6.51 6.49 6.35 6.08 5.84 5.76 5.26 5.06 4.79 4.62 4.35 4.16 4.05 3.79 3.52 3.37 3.20 2.14 2.28 2.36 2.51 2.63

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

12/23/05 12/24/05 12/25/05 12/26/05 12/27/05 12/28/05 12/29/05 12/30/05 12/31/05 01/01/06 01/02/06 01/03/06 01/04/06 01/05/06 01/06/06 01/07/06 01/08/06 01/09/06 01/10/06 01/11/06 01/12/06 01/13/06 01/14/06 01/15/06 01/16/06 01/17/06 01/18/06 01/19/06 01/20/06 01/21/06 01/22/06 01/23/06 01/24/06

5.39 5.71 5.55 6.33 5.71 5.55 6.02 6.02 6.80 6.80 7.11 7.11 7.57 6.80 6.33 6.64 6.96 6.18 6.18 7.57 6.96 6.64 6.49 6.49 5.39 5.86 6.49 6.64 6.33 6.04 6.04 5.41 6.04

4.83 5.39 5.26 5.78 5.25 4.78 5.38 5.50 5.64 6.59 6.75 6.84 7.08 6.53 6.05 6.15 6.36 5.71 5.67 6.93 6.55 6.33 6.28 6.06 5.02 5.54 6.09 6.20 5.94 5.65 5.57 5.28 5.39

11.41 6.15 2.08 3.81 4.75 8.63 8.47 6.15 8.32 6.10 6.25 6.10 6.41 5.63 5.01 5.17 5.63 4.86 5.32 6.72 5.79 5.63 5.94 5.63 4.07 4.54 5.63 5.48 4.70 5.32 5.01 4.38 4.70

2.54 0.68 0.65 1.93 2.54 5.89 3.30 3.72 6.63 5.81 5.84 5.74 5.75 5.15 4.70 4.68 4.95 4.25 4.89 5.97 5.26 5.32 5.49 5.05 3.74 4.18 4.96 4.91 4.52 4.40 4.42 4.02 3.93

8.42 7.81 6.57 7.50 7.65 8.42 8.11 7.34 8.11 7.81 7.96 7.65 7.81 7.34 7.03 7.50 7.50 7.03 7.19 8.11 7.34 7.65 7.96 7.50 6.57 6.57 7.34 7.34 6.88 7.34 7.03 6.57 6.42

7.06 6.57 5.79 6.40 6.67 7.59 7.16 6.55 7.25 7.13 7.13 7.01 7.08 6.56 6.16 6.29 6.42 6.04 6.59 7.27 6.59 7.03 7.23 6.50 5.49 5.95 6.53 6.49 6.10 6.06 5.92 5.78 5.38

5.76 4.98 4.19 4.98 4.82 6.22 5.76 4.98 6.07 5.91 5.44 5.44 5.60 5.13 4.67 4.82 5.13 4.51 4.98 5.91 5.13 5.76 5.60 5.44 3.72 4.35 5.29 4.98 4.51 4.82 4.35 4.04 4.19

216

4.90 4.22 3.66 4.45 4.42 5.34 5.08 4.46 5.46 5.34 5.14 5.02 4.96 4.44 3.94 4.06 4.30 3.71 4.36 5.30 4.49 4.99 5.23 4.46 3.07 3.71 4.49 4.32 3.91 3.83 3.68 3.36 3.32

4.63 3.84 3.22 4.16 3.84 5.26 4.79 4.16 5.26 4.94 4.47 4.47 4.63 4.16 3.37 3.84 4.16 3.37 4.01 4.94 4.16 4.79 4.63 4.32 2.74 3.37 4.32 4.01 3.22 3.69 3.37 3.22 3.22

3.94 3.20 2.74 3.65 3.54 4.61 4.14 3.63 4.64 4.46 4.22 4.05 3.99 3.46 2.94 3.15 3.42 2.74 3.36 4.38 3.54 4.03 4.31 3.51 2.05 2.78 3.54 3.39 2.90 2.90 2.72 2.38 2.40

4.51 3.57 2.94 3.73 3.41 4.66 4.19 3.57 4.51 4.35 4.04 4.19 4.35 3.73 3.09 3.41 4.19 3.09 3.26 4.51 3.88 4.04 4.19 3.73 2.62 2.46 3.88 3.57 2.78 3.41 2.94 2.94 3.09

3.48 2.98 2.66 3.39 3.18 4.02 3.62 3.22 4.05 3.90 3.69 3.59 3.53 3.04 2.67 2.82 3.10 2.39 2.97 3.84 3.08 3.57 3.90 3.00 1.82 2.28 2.97 2.99 2.53 2.52 2.41 2.10 2.05

2.92 2.92 2.76 2.76 2.76 2.92 2.92 2.76 2.92 3.08 2.92 3.08 3.08 2.92 2.76 2.76 2.76 2.76 2.60 2.76 2.60 2.76 2.76 2.76 2.44 2.28 2.44 2.81 2.49 2.96 2.49 2.33 2.49

2.64 2.65 2.68 2.76 2.69 2.79 2.79 2.75 2.85 2.85 2.85 2.88 2.82 2.76 2.67 2.67 2.63 2.42 2.53 2.61 2.48 2.53 2.61 2.54 2.30 2.22 2.32 2.47 2.41 2.40 2.11 2.02 1.99

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

01/25/06 01/26/06 01/27/06 01/28/06 01/29/06 01/30/06 01/31/06 02/01/06 02/02/06 02/03/06 02/04/06 02/05/06 02/06/06 02/07/06 02/08/06 02/09/06 02/10/06 02/11/06 02/12/06 02/13/06 02/14/06 02/15/06 02/16/06 02/17/06 02/18/06 02/19/06 02/20/06 02/21/06 02/22/06 02/23/06 02/24/06 02/25/06 02/26/06

5.26 5.10 5.10 4.63 4.63 5.41 5.26 6.04 5.41 5.10 4.78 4.00 3.53 3.37 3.21 3.68 3.21 3.05 3.37 3.53 3.84 3.53 2.89 2.89 2.42 2.58 2.58 2.74 4.16 4.16 4.94 4.47 4.78

4.60 4.72 4.75 4.22 4.08 4.97 4.79 5.07 4.95 4.56 4.21 3.55 3.14 2.86 2.87 3.14 3.00 2.67 2.80 3.06 3.50 3.10 2.46 2.42 1.85 1.87 1.99 2.53 3.14 3.64 4.23 3.99 4.36

4.23 3.29 3.44 3.13 3.29 3.92 3.60 4.23 3.76 3.60 3.29 3.13 2.66 2.66 2.66 2.97 2.97 2.66 2.97 3.29 3.13 3.13 2.82 2.66 2.19 2.34 2.50 2.34 3.44 3.60 3.92 3.92 3.92

3.39 2.72 3.00 2.64 2.65 3.59 3.04 3.53 3.13 3.16 2.86 2.56 2.14 2.07 2.10 2.31 2.33 2.04 2.27 2.50 2.75 2.51 2.07 1.98 1.52 1.68 1.63 1.90 2.54 2.71 3.13 2.95 3.24

6.11 3.62 3.93 3.47 3.78 3.93 3.47 3.93 3.15 3.47 3.15 3.15 2.68 2.84 2.84 3.15 2.99 3.15 3.15 3.47 3.31 3.47 2.99 2.99 2.37 2.52 2.84 2.37 3.31 3.47 3.78 3.78 3.78

4.70 2.94 3.19 2.75 2.94 3.52 2.93 3.20 2.74 2.76 2.59 2.43 2.08 2.03 2.06 2.23 2.35 2.16 2.33 2.56 2.68 2.56 2.28 2.12 1.78 1.85 1.83 1.96 2.45 2.51 2.79 2.72 2.93

3.72 2.29 3.09 2.46 2.77 2.93 2.77 3.41 2.93 3.09 2.62 2.93 2.46 2.62 2.62 2.93 2.77 2.77 2.93 3.25 3.09 3.09 2.77 2.62 2.14 2.29 2.46 2.14 3.09 3.09 3.41 3.57 3.41

217

2.47 1.88 2.44 1.91 2.15 2.70 2.32 2.59 2.34 2.38 2.25 2.12 1.81 1.79 1.83 1.98 2.14 1.95 2.13 2.34 2.43 2.33 2.08 1.92 1.62 1.65 1.63 1.75 2.19 2.24 2.47 2.42 2.62

2.58 2.11 2.90 2.11 2.58 2.74 2.74 3.84 2.74 2.90 2.58 2.90 2.42 2.58 2.58 2.90 2.90 2.90 3.06 3.22 3.22 3.06 2.90 2.74 2.11 2.27 2.58 2.11 3.06 3.06 3.37 3.37 3.22

1.66 1.60 2.21 1.70 1.94 2.41 2.13 2.42 2.23 2.27 2.21 2.12 1.83 1.81 1.85 2.00 2.18 2.02 2.20 2.37 2.46 2.40 2.18 2.00 1.72 1.75 1.72 1.81 2.19 2.24 2.43 2.42 2.59

2.31 2.14 2.94 2.14 2.46 2.31 2.46 2.78 2.62 2.62 2.31 2.62 2.31 2.31 2.31 2.62 2.62 2.62 2.78 2.94 3.09 2.94 2.62 2.62 1.99 2.14 2.46 1.99 2.78 2.78 3.09 3.09 2.94

1.62 1.55 2.04 1.60 1.82 2.14 1.98 2.19 2.07 2.12 2.08 2.01 1.77 1.76 1.79 1.96 2.13 2.02 2.17 2.32 2.42 2.37 2.19 1.99 1.77 1.76 1.72 1.78 2.07 2.13 2.28 2.31 2.45

2.01 1.85 2.01 1.85 1.85 1.85 1.85 2.01 2.01 2.01 2.01 2.01 1.85 1.85 1.85 2.33 2.33 2.17 2.33 2.33 2.49 2.49 2.49 2.17 2.01 2.01 1.85 1.85 2.01 2.01 2.17 2.33 2.33

1.78 1.77 1.86 1.72 1.72 1.82 1.82 1.88 1.87 1.88 1.87 1.90 1.80 1.76 1.77 2.02 2.11 2.09 2.24 2.28 2.41 2.46 2.27 2.07 1.95 1.82 1.79 1.82 1.89 1.93 2.08 2.11 2.25

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

02/27/06 02/28/06 03/01/06 03/02/06 03/03/06 03/04/06 03/05/06 03/06/06 03/07/06 03/08/06 03/09/06 03/10/06 03/11/06 03/12/06 03/13/06 03/14/06 03/15/06 03/16/06 03/17/06 03/18/06 03/19/06 03/20/06 03/21/06 03/22/06 03/23/06 03/24/06 03/25/06 03/26/06 03/27/06 03/28/06 03/29/06 03/30/06 03/31/06

5.10 6.19 5.88 5.26 5.10 5.57 4.78 4.94 5.57 5.26 4.94 4.31 4.78 4.94 5.41 5.41 4.94 6.19 6.04 6.35 6.51 6.19 6.66 7.13 7.13 7.28 6.97 7.13 7.44 8.22 7.75 8.53 8.99

4.87 5.40 5.31 4.78 4.82 5.04 4.10 4.59 4.79 4.95 4.49 4.05 4.07 4.47 4.82 5.04 4.64 5.33 5.81 5.61 5.58 5.77 6.05 6.51 6.63 6.84 6.76 6.26 6.56 7.51 7.35 7.35 8.49

3.92 4.70 4.86 4.23 4.54 4.38 3.92 4.07 4.70 4.70 4.23 3.92 4.38 4.23 5.01 4.38 4.23 5.32 5.01 5.01 5.63 5.32 5.48 6.25 6.25 6.25 5.79 6.25 6.87 6.87 6.72 7.80 7.49

3.59 4.01 3.93 3.60 3.89 3.82 3.33 3.82 3.93 3.95 3.64 3.31 3.48 3.51 3.81 3.81 3.56 4.25 4.43 4.39 4.58 4.53 4.81 5.19 5.23 5.49 5.26 5.16 5.39 6.16 5.94 6.51 6.70

3.47 4.09 4.56 4.24 4.56 3.78 3.93 3.93 4.40 4.40 4.24 3.93 4.71 4.56 4.87 4.09 4.40 5.18 4.71 5.49 5.96 5.18 5.33 5.96 5.96 5.80 5.33 6.11 6.88 6.57 5.80 7.50 6.88

3.22 3.50 3.52 3.40 3.66 3.47 3.36 3.66 3.72 3.73 3.52 3.25 3.45 3.36 3.59 3.45 3.48 3.93 4.02 4.20 4.31 4.15 4.44 4.65 4.77 4.93 4.75 4.79 5.17 5.63 5.50 6.13 6.10

3.09 3.88 4.19 3.88 4.19 3.57 3.57 3.72 4.19 4.19 4.04 3.57 4.51 4.19 4.51 3.72 4.04 4.82 4.35 5.29 5.44 4.82 4.98 5.44 5.44 5.29 4.82 5.60 6.38 6.38 5.44 7.16 6.53

218

2.86 3.18 3.19 3.14 3.40 3.21 3.12 3.39 3.45 3.48 3.27 3.01 3.21 3.10 3.30 3.18 3.22 3.64 3.69 3.91 3.97 3.82 4.07 4.27 4.39 4.52 4.38 4.44 4.83 5.27 5.14 5.72 5.70

3.06 3.69 5.41 3.84 4.16 3.69 3.53 4.01 4.16 4.16 4.01 3.53 4.32 4.16 4.32 3.69 3.84 4.63 4.32 5.10 5.26 4.47 4.79 5.10 5.26 5.10 4.79 5.41 6.19 6.03 5.41 6.97 6.51

2.81 3.08 3.17 3.13 3.34 3.22 3.16 3.36 3.44 3.45 3.27 3.02 3.20 3.10 3.27 3.14 3.21 3.53 3.61 3.83 3.87 3.75 3.97 4.14 4.28 4.39 4.29 4.37 4.76 5.15 5.04 5.57 5.59

2.94 3.26 3.73 3.73 3.88 3.57 3.41 3.41 4.04 3.88 3.88 3.57 4.04 3.88 4.04 3.57 3.73 4.35 4.19 4.66 4.82 4.19 4.51 4.82 4.98 4.66 4.51 4.98 5.76 5.76 5.13 6.53 6.22

2.63 2.87 2.98 3.00 3.24 3.12 3.11 3.27 3.33 3.34 3.19 2.99 3.13 3.03 3.17 3.07 3.13 3.40 3.45 3.65 3.70 3.62 3.79 3.94 4.07 4.17 4.12 4.25 4.59 4.92 4.85 5.28 5.39

2.49 2.64 2.81 2.96 3.12 3.12 3.12 3.12 3.28 3.28 3.28 3.12 3.12 2.96 3.12 3.12 3.12 3.28 3.28 3.44 3.44 3.44 3.59 3.75 3.91 3.91 4.07 4.22 4.54 4.69 4.69 5.01 5.32

2.40 2.56 2.73 2.89 3.05 3.08 3.07 3.12 3.13 3.13 3.12 3.02 2.99 2.90 2.99 2.99 3.01 3.09 3.19 3.24 3.35 3.39 3.49 3.55 3.72 3.83 3.93 4.05 4.34 4.52 4.66 4.77 5.19

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

04/01/06 04/02/06 04/03/06 04/04/06 04/05/06 04/06/06 04/07/06 04/08/06 04/09/06 04/10/06 04/11/06 04/12/06 04/13/06 04/14/06 04/15/06 04/16/06 04/17/06 04/18/06 04/19/06 04/20/06 04/21/06 04/22/06 04/23/06 04/24/06 04/25/06 04/26/06 04/27/06 04/28/06 04/29/06 04/30/06 05/01/06 05/02/06 05/03/06

8.22 7.75 8.53 8.83 8.53 9.61 9.14 9.30 8.83 9.14 8.83 9.30 10.71 10.24 9.77 9.14 8.68 9.30 9.92 10.71 10.86 11.02 11.02 10.71 11.64 11.95 12.42 12.57 12.73 12.42 11.95 11.33 11.48

7.76 7.20 7.91 8.58 8.28 8.53 8.56 8.79 8.37 8.42 8.27 8.58 9.58 9.90 9.33 8.26 7.64 8.21 8.87 9.71 10.41 10.18 10.18 10.21 10.48 11.03 11.44 11.75 11.82 11.88 11.10 10.65 10.58

7.03 7.03 7.49 7.49 7.33 8.42 8.11 8.42 7.80 8.11 8.26 8.72 9.64 9.18 8.57 7.64 8.11 8.88 9.64 10.43 9.80 10.12 10.12 9.96 10.89 11.04 11.36 11.20 11.66 10.89 11.20 10.58 11.04

6.40 6.13 6.74 7.15 7.10 7.31 7.07 7.49 6.95 7.18 7.07 7.50 8.23 8.04 7.91 6.95 6.93 7.27 7.87 8.55 8.69 8.72 8.57 8.84 9.19 9.36 9.63 9.65 9.91 9.88 9.48 9.33 9.36

6.73 7.19 7.19 7.19 7.19 7.81 7.81 7.96 7.34 7.65 7.96 7.96 8.42 8.11 7.81 7.34 6.88 7.34 7.65 7.96 8.11 8.27 8.11 8.42 9.33 9.49 9.64 9.49 9.96 9.49 10.58 9.96 10.42

6.02 5.93 6.34 6.66 6.59 6.69 6.45 6.86 6.42 6.65 6.73 6.99 7.34 7.27 7.43 6.97 6.60 6.85 7.07 7.49 7.76 7.75 7.54 7.89 8.30 8.51 8.61 8.50 8.77 8.77 9.08 8.64 8.82

6.38 6.69 6.69 6.84 6.84 7.46 7.31 7.62 6.84 7.31 7.62 7.93 8.08 8.08 7.31 6.69 7.31 8.08 8.54 8.86 8.54 8.39 8.54 8.54 9.48 9.63 9.63 9.48 10.09 9.48 10.09 9.48 9.94

219

5.64 5.57 5.94 6.23 6.21 6.37 6.12 6.53 6.11 6.35 6.47 6.76 6.97 7.02 6.96 6.29 6.44 6.71 7.13 7.55 7.58 7.36 7.34 7.68 8.22 8.25 8.30 8.12 8.57 8.34 8.56 8.34 8.55

6.35 6.51 6.97 6.66 6.66 7.13 7.28 7.28 6.82 7.13 7.44 7.59 7.90 8.06 7.28 6.66 7.13 7.90 8.37 8.67 8.37 8.21 8.37 8.52 9.29 9.45 9.45 9.29 9.76 9.29 10.07 9.29 9.76

5.54 5.47 5.80 6.06 6.06 6.19 6.05 6.41 6.07 6.26 6.44 6.68 6.89 6.99 6.93 6.29 6.46 6.74 7.14 7.51 7.52 7.27 7.29 7.65 8.18 8.20 8.23 8.05 8.50 8.23 8.55 8.31 8.55

6.07 6.22 6.07 6.37 6.37 6.84 6.84 6.84 6.53 6.99 7.14 7.30 7.46 7.76 7.14 6.53 6.84 7.61 8.07 8.22 8.07 7.76 7.92 8.22 8.99 8.99 8.99 8.84 9.31 8.84 9.61 8.99 9.46

5.37 5.31 5.54 5.74 5.81 5.94 5.86 6.20 5.93 6.09 6.32 6.53 6.65 6.85 6.82 6.24 6.38 6.63 7.03 7.34 7.34 7.07 7.09 7.51 8.00 8.03 8.00 7.84 8.27 8.05 8.40 8.19 8.40

5.32 5.17 5.32 5.48 5.63 5.48 5.95 5.95 5.79 5.95 6.42 6.42 6.42 6.73 6.73 6.26 6.42 6.57 7.04 7.19 7.19 6.73 7.04 7.66 7.81 7.97 7.81 7.81 8.12 7.81 8.58 7.97 8.28

5.12 5.09 5.15 5.36 5.51 5.45 5.60 5.84 5.70 5.79 6.18 6.25 6.24 6.63 6.54 6.15 6.28 6.43 6.84 7.04 6.98 6.61 6.78 7.32 7.67 7.70 7.55 7.47 7.87 7.62 8.16 7.94 8.13

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

05/04/06 05/05/06 05/06/06 05/07/06 05/08/06 05/09/06 05/10/06 05/11/06 05/12/06 05/13/06 05/14/06 05/15/06 05/16/06 05/17/06 05/18/06 05/19/06 05/20/06 05/21/06 05/22/06 05/23/06 05/24/06 05/25/06 05/26/06 05/27/06 05/28/06 05/29/06 05/30/06 05/31/06 06/01/06 06/02/06 06/03/06 06/04/06 06/05/06

12.11 12.73 12.73 12.26 12.57 11.95 12.42 13.35 13.66 13.35 14.13 14.60 14.76 15.23 14.76 15.56 15.23 14.76 13.19 14.28 14.76 14.92 14.28 12.73 12.26 12.73 14.13 14.60 15.56 15.56 16.03 17.94 18.27

11.18 11.71 12.02 11.35 11.21 11.22 11.40 12.40 12.94 12.66 13.24 13.70 14.03 14.44 14.29 14.38 14.76 13.70 12.91 12.97 13.93 14.15 13.37 11.98 11.34 12.10 12.85 13.74 14.66 15.18 14.93 16.45 16.93

11.20 11.82 11.66 11.04 11.36 11.20 11.82 12.43 12.12 12.43 12.90 13.06 13.36 13.36 12.74 13.36 13.06 12.28 11.51 12.90 13.52 13.36 12.59 11.36 11.51 12.28 13.36 13.82 14.44 13.82 14.13 15.07 15.55

9.73 10.12 10.20 9.65 9.98 9.69 9.99 10.78 10.89 10.71 11.20 11.46 11.71 11.88 11.68 11.96 12.00 11.19 10.94 11.26 11.82 11.95 11.28 10.43 10.50 11.04 11.51 12.00 12.67 12.63 12.71 13.54 13.83

10.42 10.88 10.88 9.33 10.42 10.42 11.04 11.50 10.88 11.50 11.81 11.96 12.12 11.81 11.50 11.81 11.50 10.88 10.58 11.66 12.27 11.96 10.88 10.27 11.19 11.66 12.42 12.73 13.04 12.27 13.19 13.66 14.27

8.99 9.33 9.43 8.93 9.25 9.00 9.36 9.87 9.67 9.80 10.05 10.21 10.44 10.39 10.31 10.47 10.39 9.94 9.93 10.29 10.65 10.66 10.25 9.92 10.22 10.47 10.73 10.95 11.26 11.06 11.45 11.70 11.97

9.94 10.41 10.41 9.01 9.79 9.79 10.56 10.87 10.25 10.87 11.03 11.33 11.49 11.18 11.03 11.18 10.72 10.25 10.25 11.03 11.49 11.33 10.41 9.94 10.72 11.33 11.80 11.96 12.42 11.80 12.73 13.19 13.81

220

8.66 8.99 9.13 8.66 8.90 8.71 9.09 9.52 9.24 9.46 9.62 9.79 10.03 9.94 9.91 9.97 9.89 9.54 9.55 9.87 10.20 10.22 9.89 9.69 9.95 10.16 10.33 10.51 10.77 10.62 11.03 11.25 11.45

9.92 10.23 10.38 8.98 9.61 9.76 10.38 10.69 10.07 10.69 10.85 11.01 11.16 10.85 11.01 11.01 10.54 10.07 10.07 10.69 11.31 11.16 10.38 9.92 10.69 11.16 11.47 11.78 12.09 11.47 12.24 12.71 13.18

8.63 8.93 9.10 8.67 8.86 8.71 9.08 9.45 9.13 9.41 9.51 9.67 9.91 9.79 9.80 9.78 9.72 9.48 9.48 9.78 10.13 10.10 9.86 9.73 9.97 10.14 10.28 10.41 10.56 10.42 10.76 10.93 11.05

9.46 9.77 9.92 8.84 9.31 9.31 10.08 10.23 9.61 10.39 10.39 10.54 10.70 10.39 10.54 10.54 10.08 9.77 9.77 10.39 10.70 10.70 10.23 9.92 10.39 10.70 11.01 11.16 11.32 10.85 11.62 11.78 12.24

8.47 8.73 8.93 8.55 8.66 8.57 8.92 9.25 8.92 9.21 9.30 9.43 9.68 9.55 9.58 9.53 9.45 9.30 9.33 9.57 9.87 9.90 9.72 9.67 9.84 9.96 10.07 10.16 10.22 10.08 10.33 10.45 10.50

8.43 8.58 8.89 8.43 8.43 8.28 8.89 9.05 8.58 9.05 9.21 9.36 9.52 9.21 9.36 9.05 9.21 9.21 9.21 9.21 9.52 9.52 9.67 9.67 9.67 9.67 9.83 9.83 9.67 9.67 9.67 9.67 9.67

8.18 8.35 8.59 8.36 8.28 8.25 8.62 8.84 8.41 8.79 8.82 8.92 9.15 8.96 9.05 8.91 8.89 8.96 9.01 9.11 9.40 9.45 9.51 9.61 9.67 9.67 9.70 9.66 9.60 9.57 9.58 9.56 9.55

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

06/06/06 06/07/06 06/08/06 06/09/06 06/10/06 06/11/06 06/12/06 06/13/06 06/14/06 06/15/06 06/16/06 06/17/06 06/18/06 06/19/06 06/20/06 06/21/06 06/22/06 06/23/06 06/24/06 06/25/06 06/26/06 06/27/06 06/28/06 06/29/06 06/30/06 07/01/06 07/02/06 07/03/06 07/04/06 07/05/06 07/06/06 07/07/06 07/08/06

18.43 17.94 18.11 17.62 15.39 15.23 15.07 15.23 14.92 14.92 16.19 17.30 17.94 18.11 17.78 18.59 19.58 20.56 21.54 22.55 22.89 23.41 23.23 22.21 23.06 23.23 22.89 22.89 23.06 22.04 21.71 22.21 22.55

17.41 17.35 16.75 16.00 14.47 14.71 14.53 14.59 14.26 14.20 14.97 16.25 16.57 16.99 16.70 17.00 17.70 18.61 19.46 20.55 21.07 21.73 21.98 21.11 21.05 21.78 21.79 21.33 21.99 21.02 20.90 20.90 21.23

15.87 15.39 15.55 14.29 13.67 13.67 13.36 13.36 12.90 13.98 14.92 15.23 15.55 15.71 15.39 15.55 16.18 16.81 17.77 17.93 18.89 20.03 19.06 18.57 19.54 20.03 19.22 19.87 19.38 19.22 19.22 19.71 19.71

14.44 14.06 13.56 12.55 12.17 12.33 12.30 12.54 12.20 12.42 12.99 13.72 13.86 14.17 13.95 14.18 14.52 15.22 15.94 16.42 16.99 18.09 17.83 17.53 17.48 18.33 17.92 17.92 18.03 17.49 17.87 17.98 17.95

14.58 13.19 13.35 11.66 12.42 12.58 12.42 12.73 11.96 12.89 13.66 13.96 14.12 14.27 14.27 14.90 15.37 15.69 16.01 16.16 16.63 16.79 16.16 15.37 16.94 17.11 16.32 17.27 16.01 16.32 16.79 17.27 17.42

12.25 11.46 11.66 10.91 11.09 11.23 11.24 11.39 11.10 11.46 11.79 12.02 12.08 12.29 12.25 12.45 12.85 13.26 13.57 13.73 14.07 14.47 14.24 13.97 14.47 14.66 14.47 14.79 14.49 14.44 14.96 14.95 14.92

13.97 11.96 12.73 11.18 11.80 11.96 11.96 12.27 11.49 12.27 13.04 13.35 13.51 13.66 13.81 14.28 14.75 15.07 15.38 15.54 15.86 16.02 15.22 14.75 16.33 16.49 15.86 16.49 15.54 15.70 16.02 16.65 16.65

221

11.74 10.86 11.16 10.43 10.66 10.79 10.81 10.93 10.70 11.04 11.34 11.56 11.61 11.80 11.79 11.98 12.34 12.68 12.89 13.05 13.33 13.61 13.41 13.19 13.74 13.84 13.73 14.04 13.72 13.77 14.20 14.19 14.18

13.49 11.16 12.24 11.01 11.62 11.62 11.62 11.93 11.47 12.09 12.87 13.02 13.18 13.33 13.49 13.95 14.42 14.73 14.89 15.05 15.37 15.53 14.42 14.11 15.68 15.68 15.37 15.84 15.21 15.21 15.37 16.00 16.16

11.29 10.45 10.83 10.29 10.57 10.67 10.68 10.80 10.64 10.93 11.20 11.30 11.33 11.51 11.52 11.69 12.00 12.25 12.41 12.54 12.80 12.99 12.77 12.64 13.14 13.17 13.11 13.47 13.10 13.25 13.60 13.61 13.65

12.39 10.54 11.47 10.70 11.16 11.32 11.16 11.32 11.01 11.62 12.08 12.24 12.39 12.39 12.55 13.17 13.48 13.63 13.79 13.79 14.09 14.09 13.63 13.63 14.41 14.41 14.41 14.72 14.41 14.25 14.25 14.87 15.19

10.67 10.05 10.41 10.08 10.36 10.41 10.43 10.50 10.41 10.70 10.84 10.88 10.93 11.06 11.08 11.23 11.47 11.67 11.77 11.88 12.08 12.20 12.07 12.03 12.38 12.40 12.42 12.74 12.48 12.66 12.92 12.95 13.02

9.67 9.67 9.83 9.98 9.98 9.98 9.98 10.14 10.29 10.29 10.29 10.29 10.45 10.45 10.45 10.61 10.76 10.92 10.92 10.92 11.07 11.22 11.07 11.38 11.38 11.38 11.53 11.53 11.69 11.84 11.84 12.00 12.31

9.59 9.60 9.68 9.77 9.93 9.98 9.96 10.02 10.13 10.26 10.15 10.19 10.26 10.36 10.39 10.52 10.58 10.64 10.71 10.79 10.88 10.95 11.00 11.09 11.18 11.25 11.38 11.44 11.53 11.66 11.74 11.85 12.01

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

07/09/06 07/10/06 07/11/06 07/12/06 07/13/06 07/14/06 07/15/06 07/16/06 07/17/06 07/18/06 07/19/06 07/20/06 07/21/06 07/22/06 07/23/06 07/24/06 07/25/06 07/26/06 07/27/06 07/28/06 07/29/06 07/30/06 07/31/06 08/01/06 08/02/06 08/03/06 08/04/06 08/05/06 08/06/06 08/07/06 08/08/06 08/09/06 08/10/06

23.06 23.58 23.41 23.23 22.72 23.23 23.75 23.75 23.75 23.41 22.89 23.06 23.92 24.44 25.13 25.31 25.13 24.78 24.44 24.44 24.27 23.92 22.21 21.21 21.38 21.71 22.21 22.21 22.55 24.34 23.99 23.13 22.63

21.66 22.29 22.26 22.06 21.67 21.92 22.40 22.67 22.70 22.20 21.84 21.83 22.59 23.23 23.92 24.13 24.06 23.73 23.40 23.42 23.23 22.44 20.64 20.16 20.26 20.47 20.97 21.19 21.41 22.36 22.17 21.57 21.16

20.19 20.19 20.19 20.03 20.19 20.68 20.84 20.84 20.84 20.68 20.19 21.01 21.33 22.33 22.83 22.49 22.16 22.16 22.00 22.16 21.67 20.84 19.22 19.87 19.71 20.35 20.84 21.01 20.68 22.00 21.33 20.68 20.51

18.53 18.80 18.79 18.76 18.50 18.92 19.28 19.37 19.45 19.18 18.82 19.16 19.73 20.33 20.99 21.05 20.81 20.44 20.27 20.47 20.19 19.58 18.20 18.36 18.28 18.65 19.22 19.47 19.28 19.77 19.96 19.37 19.12

17.58 17.42 17.91 17.42 17.74 18.07 18.23 18.39 18.55 18.23 18.07 18.71 19.03 19.03 19.19 19.36 19.03 19.19 19.36 19.19 19.19 18.71 18.39 18.55 18.71 19.03 19.19 19.03 19.36 19.84 19.36 19.19 19.52

15.29 15.33 15.49 15.45 15.46 15.75 15.92 16.06 16.23 16.06 15.93 16.24 16.60 16.83 17.08 17.17 17.02 17.06 17.01 17.15 17.09 16.81 16.37 16.60 16.46 16.76 17.05 17.12 17.30 17.59 17.44 17.26 17.37

16.97 16.81 17.13 16.81 17.13 17.44 17.61 17.76 17.92 17.61 17.61 18.08 18.41 18.41 18.57 18.57 18.24 18.57 18.73 18.57 18.57 18.08 17.92 17.92 18.08 18.41 18.73 18.57 18.89 19.22 18.73 18.73 19.06

222

14.48 14.53 14.72 14.66 14.72 14.99 15.14 15.23 15.42 15.30 15.21 15.54 15.87 16.06 16.26 16.34 16.18 16.26 16.21 16.35 16.29 16.06 15.74 15.97 15.87 16.13 16.40 16.48 16.63 16.87 16.72 16.66 16.80

16.32 16.16 16.48 16.32 16.48 16.79 16.95 17.11 17.27 17.11 16.95 17.43 17.75 17.91 17.91 18.07 17.75 17.91 18.07 18.07 18.07 17.75 17.59 17.59 17.75 18.07 18.39 18.23 18.39 18.72 18.23 18.39 18.88

13.90 13.94 14.14 14.09 14.20 14.44 14.58 14.68 14.86 14.76 14.69 15.04 15.30 15.46 15.61 15.73 15.60 15.68 15.68 15.79 15.77 15.61 15.37 15.60 15.56 15.79 16.02 16.08 16.25 16.45 16.32 16.35 16.50

15.19 15.03 15.51 15.19 15.51 15.82 15.98 16.14 16.14 15.98 15.98 16.46 16.77 16.77 16.93 16.93 16.77 16.93 17.08 17.08 17.08 16.93 16.77 16.93 17.08 17.24 17.56 17.56 17.56 17.88 17.56 17.72 18.04

13.21 13.15 13.48 13.44 13.59 13.81 13.93 14.04 14.19 14.14 14.10 14.44 14.61 14.77 14.88 15.01 14.92 15.02 15.05 15.15 15.16 15.08 14.95 15.12 15.14 15.31 15.52 15.60 15.72 15.89 15.83 15.90 16.05

12.31 12.47 12.47 12.62 12.78 12.93 12.93 13.09 13.24 13.24 13.40 13.40 13.56 13.71 13.86 13.86 14.02 14.02 14.17 14.17 14.33 14.33 14.33 14.48 14.64 14.64 14.80 14.96 15.12 15.12 15.12 15.28 15.44

12.06 12.23 12.38 12.46 12.55 12.74 12.83 12.95 13.05 13.14 13.24 13.33 13.45 13.56 13.64 13.74 13.81 13.88 14.01 14.08 14.14 14.25 14.27 14.37 14.45 14.51 14.65 14.77 14.85 14.94 15.02 15.16 15.29

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

08/11/06 08/12/06 08/13/06 08/14/06 08/15/06 08/16/06 08/17/06 08/18/06 08/19/06 08/20/06 08/21/06 08/22/06 08/23/06 08/24/06 08/25/06 08/26/06 08/27/06 08/28/06 08/29/06 08/30/06 08/31/06 09/01/06 09/02/06 09/03/06 09/04/06 09/05/06 09/06/06 09/07/06 09/08/06 09/09/06 09/10/06 09/11/06 09/12/06

22.30 21.47 21.47 21.80 22.63 22.30 21.13 21.47 21.47 21.63 21.30 21.80 21.13 19.99 20.31 20.64 21.30 21.47 22.13 21.13 19.18 19.02 19.51 19.18 20.47 21.97 21.97 21.30 20.64 21.13 20.64 20.31 20.15

20.61 20.18 19.74 19.97 21.01 20.61 19.49 19.81 19.82 19.91 20.17 20.28 20.08 19.08 19.03 19.06 19.54 19.89 20.49 19.36 17.64 17.27 17.64 17.97 18.74 20.09 20.61 20.20 19.49 19.66 19.38 18.76 18.61

20.35 20.03 20.03 20.51 20.84 20.51 20.03 20.19 20.19 20.19 20.03 20.68 19.87 18.89 19.54 19.71 20.19 20.51 21.33 20.03 18.89 19.06 20.03 19.71 21.17 21.50 21.33 20.35 20.51 20.68 20.35 20.03 20.03

18.91 18.59 18.35 18.83 19.38 19.07 18.41 18.59 18.73 18.78 18.91 19.14 18.92 18.10 18.27 18.27 18.78 19.12 19.75 18.78 17.22 17.15 17.87 18.20 19.21 19.90 20.01 19.36 19.07 19.20 18.86 18.39 18.35

19.19 19.03 19.36 19.52 19.52 19.19 19.36 19.52 19.68 19.68 19.52 19.84 19.52 18.55 19.19 19.68 20.00 20.64 20.48 19.52 19.03 19.43 19.75 19.75 20.07 20.39 19.91 19.75 20.07 19.75 19.91 19.75 19.91

17.30 17.16 17.12 17.45 17.70 17.64 17.38 17.50 17.60 17.64 17.83 17.95 17.79 17.30 17.68 17.67 18.06 18.42 18.74 17.94 17.20 17.49 17.99 18.18 18.56 18.95 18.83 18.67 18.71 18.57 18.48 18.19 18.31

18.73 18.57 18.89 19.22 19.22 19.06 18.89 19.22 19.38 19.38 19.22 19.38 19.22 18.24 18.73 19.38 19.55 20.36 20.03 18.73 18.89 19.44 19.60 19.44 20.09 20.41 21.40 19.60 19.76 19.76 19.92 19.76 20.41

223

16.76 16.65 16.64 16.96 17.17 17.13 16.93 17.05 17.15 17.19 17.34 17.47 17.32 16.92 17.28 17.34 17.63 17.98 18.15 17.40 16.87 17.16 17.53 17.63 18.05 18.34 18.22 18.01 18.10 18.04 17.96 17.72 17.90

18.39 18.39 18.72 18.88 18.88 19.04 18.88 19.04 19.21 19.21 19.04 19.21 19.04 18.07 18.56 19.21 19.54 20.03 19.86 18.72 19.04 19.37 19.54 19.21 19.54 19.86 19.37 19.37 19.70 19.54 19.54 19.54 19.70

16.47 16.42 16.45 16.72 16.90 16.90 16.76 16.87 16.98 17.01 17.12 17.26 17.12 16.79 17.15 17.24 17.47 17.78 17.84 17.19 16.86 17.14 17.40 17.48 17.76 18.07 17.95 17.84 17.95 17.85 17.82 17.60 17.74

17.88 17.88 18.04 18.20 18.20 18.36 18.20 18.36 18.52 18.52 18.52 18.68 18.52 17.72 18.20 18.68 18.84 19.49 19.17 18.52 18.84 19.17 19.17 18.68 19.17 19.33 19.01 18.84 19.17 19.01 19.17 19.17 19.33

16.07 16.05 16.13 16.33 16.50 16.52 16.43 16.54 16.64 16.69 16.75 16.92 16.82 16.62 16.87 17.01 17.16 17.42 17.42 16.96 16.86 17.03 17.21 17.19 17.45 17.66 17.57 17.54 17.62 17.56 17.58 17.43 17.55

15.59 15.59 15.76 15.91 15.91 15.91 16.07 16.07 16.23 16.39 16.39 16.54 16.54 16.54 16.71 16.71 16.86 16.86 16.86 16.86 17.02 17.02 17.02 17.02 17.18 17.18 17.18 17.18 17.18 17.18 17.34 17.34 17.34

15.35 15.47 15.54 15.65 15.72 15.82 15.94 15.99 16.08 16.15 16.22 16.31 16.37 16.44 16.50 16.58 16.62 16.68 16.74 16.76 16.79 16.84 16.87 16.91 16.94 16.98 17.04 17.07 17.08 17.08 17.12 17.17 17.20

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

09/13/06 09/14/06 09/15/06 09/16/06 09/17/06 09/18/06 09/19/06 09/20/06 09/21/06 09/22/06 09/23/06 09/24/06 09/25/06 09/26/06 09/27/06 09/28/06 09/29/06 09/30/06 10/01/06 10/02/06 10/03/06 10/04/06 10/05/06 10/06/06 10/07/06 10/08/06 10/09/06 10/10/06 10/11/06 10/12/06 10/13/06 10/14/06 10/15/06

20.31 19.18 17.24 15.65 16.28 16.28 15.81 15.81 16.44 15.81 15.81 15.97 16.44 16.76 17.08 17.40 17.72 16.92 16.44 15.81 15.97 16.44 16.92 16.28 15.65 15.02 14.23 13.77 13.92 13.77 13.92 14.08 13.46

18.83 17.56 15.45 14.30 14.76 15.11 14.95 14.59 15.56 14.67 14.47 14.62 14.97 15.32 15.62 16.02 16.29 15.97 15.55 15.06 14.77 15.55 15.71 15.60 14.81 14.03 13.43 12.78 12.75 12.70 12.77 12.93 12.44

20.51 18.41 16.49 16.02 17.13 17.45 16.34 16.65 17.45 16.65 16.81 17.13 17.45 17.77 17.93 18.09 18.41 17.45 16.97 15.55 16.81 17.77 17.61 16.65 16.34 15.55 14.60 14.66 14.98 14.82 14.98 14.98 13.88

18.65 17.34 15.30 14.85 15.37 15.83 15.74 15.42 16.18 15.06 14.96 15.27 15.66 15.94 16.10 16.44 16.60 16.17 15.78 15.19 15.16 16.20 16.08 15.80 15.06 14.27 13.81 13.31 13.55 13.49 13.58 13.72 13.30

19.91 18.94 17.17 17.49 18.14 18.46 17.98 17.66 17.49 17.17 17.66 17.82 17.98 18.14 18.14 18.30 18.30 17.82 17.49 16.69 17.42 17.58 17.74 17.27 16.63 16.16 15.84 15.69 15.53 15.69 15.84 15.84 15.22

18.49 17.22 16.27 16.25 16.65 17.00 16.65 16.48 16.78 15.98 16.20 16.42 16.66 16.84 16.87 17.04 17.06 16.67 16.51 15.92 16.06 16.67 16.52 16.30 15.87 15.17 14.99 14.77 14.68 14.55 14.77 14.78 14.29

20.57 17.33 17.97 17.97 18.62

18.13 18.29 18.46 18.29 17.81 17.17 16.37 17.52 17.36 17.68 17.21 16.57 16.24 15.61 15.77 15.77 15.77 15.93 15.77 14.82

224

17.59 15.10 12.91 13.06 13.86 14.99 14.56 15.25 16.06 14.37 12.82 13.09 13.86 13.01 16.64 16.76 16.71 16.34 16.12 15.64 15.99 16.44 16.38 16.07 15.74 15.09 14.91 14.76 14.64 14.51 14.71 14.63 14.07

19.70 17.75 17.59 17.75 18.56 18.72 17.43 17.75 17.75 17.75 18.07 18.23 18.39 18.39 18.39 18.39 18.39 17.91 17.27 16.16 17.59 17.11 17.75 16.95 16.63 16.48 15.68 16.00 15.84 16.00 16.00 15.68 14.42

17.83 16.77 16.26 16.32 16.71 16.90 16.42 16.48 16.69 16.03 16.26 16.38 16.54 16.59 16.61 16.69 16.63 16.30 16.05 15.57 15.91 16.18 16.22 15.86 15.62 15.07 14.89 14.75 14.59 14.43 14.55 14.39 13.82

19.33 17.88 18.04 17.88 18.68 18.68 16.93 17.88 18.04 18.04 18.20 18.20 18.36 18.36 18.36 18.20 18.20 17.88 17.24 16.29 17.40 17.24 17.72 16.61 16.61 16.61 15.98 16.29 15.98 16.14 16.14 15.82 14.72

17.58 16.85 16.58 16.67 16.92 16.98 16.57 16.71 16.81 16.33 16.48 16.52 16.61 16.60 16.57 16.60 16.54 16.26 16.04 15.65 15.94 16.09 16.16 15.83 15.69 15.27 15.09 15.00 14.83 14.66 14.71 14.52 13.92

17.34 17.34 17.50 17.34 17.34 17.34 17.18 17.18 17.02 17.02 16.86 16.86 16.86 16.71 16.71 16.54 16.54 16.39 16.39 16.07 16.07 16.07 16.07 15.91 15.91

17.23 17.20 17.27 17.21 17.21 17.09 17.05 17.03 16.94 16.81 16.74 16.70 16.62 16.58 16.46 16.43 16.40 16.24 16.18 16.07 15.95 15.96 15.96 15.90 15.77

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

10/16/06 10/17/06 10/18/06 10/19/06 10/20/06 10/21/06 10/22/06 10/23/06 10/24/06 10/25/06 10/26/06 10/27/06 10/28/06 10/29/06 10/30/06 10/31/06 11/01/06 11/02/06 11/03/06 11/04/06 11/05/06 11/06/06 11/07/06 11/08/06 11/09/06 11/10/06 11/11/06 11/12/06 11/13/06 11/14/06 11/15/06 11/16/06 11/17/06

12.84 13.00 13.00 13.16 13.46 12.69 12.07 11.91 11.76 11.29 10.83 10.83 10.98 10.83 10.05 8.50 7.42 7.42 9.74 12.07 12.07 13.16 14.08 14.08 12.22 9.58 9.58 8.81 8.96 9.43 8.34 9.58 9.58

12.15 12.15 11.93 12.55 12.55 11.77 11.13 10.94 10.90 10.66 9.99 9.88 9.96 9.94 9.00 7.60 6.63 6.72 8.41 10.85 11.87 12.58 13.51 13.43 10.88 8.67 8.80 8.25 8.52 8.79 7.91 8.58 9.16

13.88 13.73 13.27 13.58 14.04 12.96 12.49 12.49 12.34 11.41 10.79 11.10 11.41 11.41 10.02 8.16 7.54 7.86 10.17 12.49 12.18 13.27 13.88 13.73 11.41 8.93 9.55 8.63 8.63 8.93 8.01 10.02 9.39

12.93 12.64 12.18 12.78 12.91 11.81 11.21 11.17 11.07 10.69 9.91 9.76 10.01 10.17 9.17 7.41 6.55 7.07 8.87 11.19 11.81 12.58 13.27 13.09 10.19 8.30 8.66 7.94 8.14 8.32 7.47 8.69 8.76

14.58 14.43 13.96 14.43 14.27 13.66 13.50 13.35 13.35 12.73 11.66 12.12 12.58 12.58 11.50 9.49 9.33 9.64 11.66 13.19 12.89 13.35 13.96 13.66 11.34 9.64 10.27 9.64 9.96 9.96 9.49 10.58 10.11

13.87 13.50 13.12 13.80 13.58 12.72 12.40 12.42 12.40 11.99 10.93 11.06 11.37 11.43 10.14 8.66 8.29 8.77 10.50 12.15 12.35 12.67 13.20 12.75 10.18 9.01 9.51 8.83 9.32 9.31 8.75 9.72 9.53

14.51 14.35 13.88 14.19 14.04 13.27 13.27 13.12 13.12 12.49 11.41 11.87 12.34 12.34 11.25 9.23 9.03 9.49 11.52 13.07 12.29 12.61 13.38 13.23 10.74 9.03 9.34 9.03 9.18 9.49 8.72 9.81 9.49

225

13.69 13.33 12.89 13.67 13.36 12.38 12.08 12.05 12.08 11.62 10.54 10.76 11.18 11.20 9.81 8.35 8.03 8.48 10.37 11.95 11.91 12.14 12.68 12.20 9.55 8.31 8.71 8.08 8.50 8.56 7.94 8.92 8.84

14.26 14.11 13.79 13.95 13.79 12.87 12.87 12.56 12.71 12.09 10.85 11.78 12.09 11.93 10.54 8.67 8.67 9.14 11.31 12.56 11.62 12.09 12.87 12.40 9.92 8.21 8.67 8.52 8.67 8.67 8.06 8.98 8.83

13.46 13.06 12.61 13.32 12.97 11.76 11.51 11.40 11.42 10.88 9.74 10.15 10.80 10.82 9.32 7.94 7.65 8.08 10.04 11.57 11.41 11.56 12.10 11.59 8.91 7.67 8.13 7.72 8.05 8.17 7.41 8.19 8.19

14.87 15.03 14.41 13.94 14.72 14.41 14.09 13.94 13.79 12.24 11.93 12.55 12.71 12.55 10.70 10.08 9.61 9.46 11.47 12.86 11.47 11.78 12.55 11.78 9.61 8.69 8.99 9.31 8.84 9.31 8.22 9.46 9.15

13.76 13.38 13.01 13.50 13.14 12.01 11.80 11.68 11.69 10.98 10.05 10.59 11.19 11.17 9.78 8.73 8.36 8.74 10.35 11.55 11.20 11.25 11.67 11.20 8.88 7.82 8.25 8.11 8.24 8.40 7.53 8.21 8.40

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

11/18/06 11/19/06 11/20/06 11/21/06 11/22/06 11/23/06 11/24/06 11/25/06 11/26/06 11/27/06 11/28/06 11/29/06 11/30/06 12/01/06 12/02/06 12/03/06 12/04/06 12/05/06 12/06/06 12/07/06 12/08/06 12/09/06 12/10/06 12/11/06 12/12/06 12/13/06 12/14/06 12/15/06 12/16/06 12/17/06 12/18/06 12/19/06 12/20/06

10.05 9.74 10.52 11.44 10.67 9.27 8.19 8.04 7.73 7.11 6.49 4.77 3.99 4.46 4.93 4.30 4.14 4.62 4.62 4.62 4.77 5.39 6.33 6.33 7.42 8.19 8.81 8.50 7.11 4.93 3.83 3.37 3.37

9.37 9.27 9.87 10.64 10.14 8.65 7.74 7.64 7.00 6.86 5.73 3.82 3.73 3.83 4.29 3.87 3.49 3.78 4.02 4.00 4.09 4.77 5.74 6.00 6.92 7.86 8.37 8.07 5.86 4.28 3.29 2.84 2.80

9.71 9.39 10.02 10.79 9.86 8.47 8.01 8.01 7.23 6.93 5.99 4.12 3.81 4.12 4.43 3.81 3.66 3.97 4.12 4.28 4.75 5.06 5.84 6.15 6.77 7.39 7.86 7.70 5.99 3.97 2.87 2.56 2.56

8.90 8.91 9.49 10.14 9.05 8.09 7.28 7.33 6.56 6.50 5.36 3.40 3.26 3.48 3.79 3.30 2.90 3.08 3.45 3.57 3.85 4.46 5.26 5.62 6.41 7.05 7.53 7.30 4.96 3.32 2.30 1.95 1.86

10.88 10.58 10.88 10.73 9.96 9.33 9.03 9.03 8.57 7.96 7.50 5.96 5.80 6.11 6.26 5.49 5.33 5.49 5.80 5.96 6.11 6.73 6.88 7.03 7.50 7.81 7.96 7.96 6.26 4.87 4.09 3.78 3.93

9.94 9.86 10.18 10.06 9.27 8.67 8.16 8.29 7.70 7.64 6.69 4.91 5.11 5.24 5.51 4.91 4.58 4.82 5.12 5.25 5.38 5.76 6.16 6.47 7.04 7.38 7.52 7.42 5.32 3.93 3.33 3.10 3.16

10.27 9.96 10.27 10.12 9.34 8.56 8.26 8.26 7.63 7.17 6.70 4.83 5.14 5.67 5.67 4.88 4.73 5.04 5.36 5.67 5.82 6.29 6.29 6.60 6.91 7.22 7.38 7.38 5.67 3.94 3.32 3.32 3.48

226

9.36 9.19 9.45 9.56 8.77 7.84 7.33 7.46 6.81 6.72 5.69 3.82 4.22 4.54 4.84 4.15 3.84 4.15 4.50 4.68 4.86 5.31 5.64 5.96 6.55 6.85 6.96 6.86 4.60 3.13 2.59 2.42 2.54

9.61 9.14 9.45 9.76 8.98 7.74 7.59 7.74 6.97 6.51 5.88 4.01 4.47 5.10 4.79 4.16 3.84 4.32 4.63 4.94 5.10 5.41 5.41 5.72 6.03 6.19 6.51 6.35 4.63 2.90 2.58 2.42 2.55

8.76 8.53 8.89 9.28 8.39 7.32 6.73 6.97 6.40 6.22 5.27 3.44 3.64 3.97 4.17 3.46 3.10 3.42 3.76 3.96 4.08 4.52 4.80 5.11 5.63 5.92 6.12 5.97 3.71 2.29 1.75 1.58 1.76

9.92 9.31 9.31 9.92 8.84 8.07 7.61 7.92 6.99 6.84 6.22 4.82 4.98 5.76 5.60 4.82 4.66 4.98 5.29 5.29 5.44 5.44 5.44 5.91 5.76 5.91 6.22 6.22 4.66 3.57 3.26 3.09 3.26

8.79 8.58 8.86 9.16 8.17 7.36 6.77 7.19 6.63 6.44 5.55 4.09 4.16 4.69 4.66 3.92 3.68 3.97 4.25 4.36 4.42 4.79 4.89 5.14 5.46 5.67 5.81 5.71 3.76 2.72 2.28 2.14 2.26

8.74 8.43 8.28 8.12 7.81 7.66 7.35 7.35 7.04 6.73 6.57 6.42 6.42 6.26 6.11 5.79 5.79 5.79 5.63 5.63 5.63 5.63 5.48 5.32 5.01 4.69 4.69

8.30 8.04 7.96 7.76 7.40 7.10 7.02 6.98 6.72 6.37 6.15 6.03 6.00 5.83 5.76 5.66 5.62 5.61 5.56 5.56 5.54 5.50 5.22 4.90 4.65 4.42 4.30

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

12/21/06 12/22/06 12/23/06 12/24/06 12/25/06 12/26/06 12/27/06 12/28/06 12/29/06 12/30/06 12/31/06 01/01/07 01/02/07 01/03/07 01/04/07 01/05/07 01/06/07 01/07/07 01/08/07 01/09/07 01/10/07 01/11/07 01/12/07 01/13/07 01/14/07 01/15/07 01/16/07 01/17/07 01/18/07 01/19/07 01/20/07 01/21/07 01/22/07

3.21 4.46 3.83 4.62 5.10 6.19 6.97 5.88 4.16 4.16 4.47 4.31 4.63 5.57 6.19 5.41 4.94 5.10 6.66 6.66 5.72 4.78 2.74 1.62 2.26 2.26 1.78 2.10 2.42 3.21 4.00 3.84 4.47

2.81 3.77 3.50 4.05 4.81 5.59 6.50 4.95 3.76 3.62 4.03 4.01 4.36 4.99 5.73 4.54 4.35 4.49 5.79 6.22 5.33 3.87 1.66 0.99 1.58 1.57 1.27 1.26 1.73 2.56 3.12 3.21 3.55

2.39 3.49 3.34 4.28 4.12

1.95 2.71 2.81 3.75 3.91

3.93 4.56 5.02 5.33 5.80 6.57 6.88 5.80 4.40 4.40 4.56 4.71 5.18 6.11 5.96 5.02 4.62 5.40 6.18 4.30 4.14 3.05 2.26 2.57 3.21 2.73 2.42 2.42 3.05 3.52 3.83 3.83 4.30

3.30 3.74 4.02 4.61 5.21 5.69 6.27 4.36 3.42 3.52 3.79 3.80 4.39 5.13 5.24 4.27 3.86 3.97 4.89 3.66 3.74 2.42 1.50 1.30 2.28 1.76 1.66 1.60 1.97 2.52 2.75 2.77 3.27

3.32 4.10 4.26 4.73 5.20 5.82 6.44 5.04 3.48 3.48 3.63 3.79 4.10 4.73 4.57 3.79 3.16 3.79 4.88 3.79 3.48 2.37 1.57 1.41 1.89 1.25 1.09 1.09 1.41 2.05 2.53 2.53 3.32

227

2.68 3.22 3.43 4.04 4.72 5.21 5.73 3.46 2.51 2.61 2.87 2.98 3.51 3.91 3.94 2.75 2.40 2.65 3.68 3.04 3.07 1.85 0.98 0.66 1.09 0.58 0.41 0.40 0.71 1.23 1.46 1.49 2.00

2.23 3.18 3.02 3.81 4.13 4.91 5.38 3.81 2.55 2.71 2.87 2.87 3.18 3.66 3.66 7.41 2.55 3.02 3.81 3.50 3.18 2.23 1.59 1.11 1.11 0.63 0.31 0.31 0.79 1.27 1.76 1.92 2.55

1.76 2.35 2.46 3.17 3.82 4.33 4.80 2.49 1.69 1.81 2.04 2.13 2.69 3.20 3.27 2.06 1.77 1.98 3.01 2.72 2.68 1.65 0.89 0.46 0.51 0.21 0.04 0.03 0.23 0.59 0.77 0.85 1.30

2.46 3.73 2.94 4.19 4.04 4.66 4.98 3.41 2.94 3.09 2.94 2.94 3.26 3.26 3.88 2.46 2.62 2.78 3.41 3.41 2.78 2.46 1.99 1.52 1.52 1.36 1.04 0.88 1.36 1.83 1.83 2.31 2.62

2.23 2.65 2.61 3.36 3.72 4.23 4.48 2.46 1.99 2.05 2.17 2.26 2.71 3.03 2.99 1.88 1.81 1.86 2.79 2.66 2.56 1.87 1.27 0.73 0.79 0.50 0.24 0.17 0.41 0.70 0.88 1.03 1.40

4.22 4.54 4.07 4.22 4.07 4.07 4.07 3.91 3.59 3.28 2.96 3.12 2.81 2.64 3.12 2.96 2.81 3.12 2.51 2.51 2.51 2.51 2.35 2.03 2.35 2.03 1.55 1.71 1.87 1.71 2.35 2.19 2.03

4.15 4.13 3.94 3.93 3.89 3.94 3.87 3.57 3.35 3.07 2.82 2.94 2.66 2.57 2.67 2.70 2.52 2.29 2.40 2.43 2.44 2.40 2.19 1.92 2.11 1.74 1.29 1.56 1.66 1.52 2.02 2.09 1.76

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

01/23/07 01/24/07 01/25/07 01/26/07 01/27/07 01/28/07 01/29/07 01/30/07 01/31/07 02/01/07 02/02/07 02/03/07 02/04/07 02/05/07 02/06/07 02/07/07 02/08/07 02/09/07 02/10/07 02/11/07 02/12/07 02/13/07 02/14/07 02/15/07 02/16/07 02/17/07 02/18/07 02/19/07 02/20/07 02/21/07 02/22/07 02/23/07 02/24/07

4.78 4.47 4.47 4.78 4.63 4.47 4.31 5.41 5.10 4.63 4.00 3.68 6.04 6.82 7.44 6.82 8.37 8.99 8.53 8.68 8.68 8.53 8.53 8.53 9.46 10.39 9.46 8.22 8.06 7.59 7.91 7.91 6.97

3.91 3.75 3.70 3.83 3.80 3.62 3.48 4.42 4.34 3.99 3.23 3.02 4.72 5.94 6.58 6.40 7.21 8.20 7.89 8.28 8.16 7.61 7.53 8.08 8.74 9.31 8.54 7.40 7.55 7.23 7.13 7.46 5.93

4.30 4.30 4.46 4.46 4.62 4.46 4.30 4.77 4.62 4.42 3.80 4.11 6.29 6.45 6.76 6.14 7.07 7.53 7.23 7.38 7.23 6.61 6.45 6.61 7.69 8.00 7.69 6.45 6.92 6.92 6.45 6.29 5.67

3.30 3.25 3.46 3.46 3.40 3.29 3.16 3.86 3.59 3.48 2.88 2.88 4.67 5.30 5.71 5.45 6.01 6.62 6.29 6.71 6.51 5.87 5.71 6.22 6.77 7.03 6.64 5.71 6.19 6.22 5.99 5.91 4.85

3.16 3.16 3.48 3.48 3.48 3.16 3.16 3.94 3.79 3.32 2.85 3.16 5.20 5.67 5.98 5.20 6.29 6.91 6.29 6.91 6.29 5.98 5.98 5.67 7.22 7.69 6.44 5.51 6.44 5.67 5.51 5.20 4.10

228

2.00 2.00 2.20 2.23 2.23 1.96 1.99 2.84 2.61 2.35 1.73 1.86 3.70 4.33 4.70 4.30 4.95 5.57 5.17 5.69 5.33 4.57 4.53 5.06 5.75 6.01 5.21 4.31 5.14 4.97 4.69 4.45 3.27

2.39 2.55 2.71 2.71 2.87 2.55 2.55 3.18 3.18 2.71 2.07 2.39 4.43 4.74 5.05 4.27 5.36 5.67 5.52 5.98 5.52 5.21 5.21 4.89 6.14 6.76 5.05 4.89 5.52 4.74 4.58 4.27 3.33

1.30 1.32 1.50 1.49 1.50 1.34 1.26 2.00 1.84 1.59 1.02 1.13 2.86 3.47 3.78 3.31 3.95 4.55 4.26 4.73 4.36 3.67 3.59 4.04 4.74 5.05 4.26 3.42 4.25 4.06 3.74 3.44 2.40

2.46 2.78 2.78 2.78 2.94 2.78 2.62 3.26 3.09 2.94 2.62 2.78 4.19 4.51 4.66 3.57 4.82 5.13 5.13 4.98 4.82 4.82 4.66 3.88 5.76 6.07 4.35 4.51 5.13 4.19 4.04 3.57 3.09

1.33 1.39 1.50 1.49 1.53 1.41 1.29 1.95 1.83 1.63 1.16 1.33 2.66 3.21 3.42 3.01 3.45 3.99 3.69 4.09 3.63 3.34 3.20 3.54 4.10 4.36 3.84 2.96 3.88 3.68 3.33 3.07 2.22

2.03 1.87 2.03 2.03 2.03 1.87 2.03 2.51 2.35 2.51 2.51 2.35 2.67 2.35 2.51 1.87 2.19 2.03 2.19 2.19 2.64 2.64 2.96 2.33 2.96 2.96 2.35 2.82 2.82 2.82 2.82 2.67 2.67

1.74 1.66 1.64 1.80 1.91 1.65 1.84 2.19 2.15 2.14 2.19 2.04 2.29 2.17 2.09 1.75 1.89 1.86 1.85 1.91 2.12 2.20 2.28 2.28 2.40 2.39 2.26 2.49 2.55 2.54 2.58 2.54 2.45

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

02/25/07 02/26/07 02/27/07 02/28/07 03/01/07 03/02/07 03/03/07 03/04/07 03/05/07 03/06/07 03/07/07 03/08/07 03/09/07 03/10/07 03/11/07 03/12/07 03/13/07 03/14/07 03/15/07 03/16/07 03/17/07 03/18/07 03/19/07 03/20/07 03/21/07 03/22/07 03/23/07 03/24/07 03/25/07 03/26/07 03/27/07 03/28/07 03/29/07

6.35 6.82 7.59 7.28 6.35 7.28 7.75 9.14 9.77 11.17 11.79 11.95 11.02 11.95 13.04 13.51 13.82 13.51 12.57 12.73 13.82 14.60 14.76 14.28 12.42 11.64 13.82 14.28 13.82 12.57 11.95 10.39 11.64

5.72 6.12 6.62 6.72 6.01 6.34 7.04 7.90 8.61 9.79 10.87 10.91 10.39 10.53 11.75 12.42 12.83 12.66 11.50 11.31 11.96 13.05 13.29 12.95 10.64 10.19 11.70 12.57 13.09 11.63 10.88 9.23 9.82

5.82 6.29 6.29 6.29 5.82 5.98 6.76 8.00 8.15 9.08 9.74 10.52 9.27 10.52 11.61 11.92 12.07 11.76 10.68 11.61 12.54 13.01 12.85 12.23 10.37 10.52 12.54 13.32 12.69 11.92 11.14 10.83 11.61

5.18 5.57 5.78 5.64 5.19 5.16 5.92 6.87 7.33 8.00 8.83 9.15 8.32 8.64 9.71 10.49 10.97 10.39 8.80 9.54 10.38 11.01 11.03 10.33 8.70 9.09 10.46 11.16 11.53 10.26 9.93 8.84 9.35

5.04 3.99 5.98 4.51 5.98 4.79 5.20 4.33 4.73 3.85 5.51 4.08 6.60 5.16 8.16 6.27 8.16 6.49 9.08 7.20 9.39 7.74 9.70 8.20 8.16 7.17 9.39 7.53 10.94 8.71 11.56 9.49 11.41 9.80 10.94 9.18 9.39 7.51 10.94 8.48 11.87 9.31 12.34 9.87 12.49 9.93 11.10 8.91 9.39 7.44 9.86 8.00 12.18 9.47 12.96 10.26 12.03 10.36 11.25 9.20 10.63 8.90 10.17 7.91 10.94 8.51

229

3.96 5.05 5.21 4.27 3.65 4.74 5.83 7.38 7.58 8.35 8.46 8.77 6.92 8.77 10.00 10.62 10.31 9.69 8.46 9.84 11.08 11.23 11.70 9.22 8.46 9.22 11.39 12.48 10.47 10.77 9.38 9.69 10.47

3.10 3.61 3.88 3.35 2.90 3.23 4.29 5.37 5.54 6.19 6.75 7.17 6.03 6.48 7.69 8.46 8.59 8.01 6.45 7.43 8.22 8.76 8.85 7.69 6.43 6.95 8.44 9.32 9.27 8.29 7.90 7.02 7.71

3.73 4.66 4.82 3.88 3.26 4.66 5.60 6.68 6.68 7.46 7.76 7.92 5.76 8.07 8.84 9.46 8.53 8.22 7.76 8.99 9.61 9.92 10.23 8.07 8.53 8.22 10.39 11.01 9.31 10.08 7.76 9.31 10.23

2.82 3.29 3.55 3.05 2.71 3.07 4.07 4.82 4.88 5.37 6.03 6.26 5.26 5.62 6.80 7.52 7.36 6.88 5.66 6.59 7.18 7.66 7.78 6.81 5.91 6.25 7.59 8.37 8.37 7.57 7.33 6.39 7.26

2.67 2.82 2.98 2.67 2.82 3.14 2.98 3.14 3.14 3.30 3.46 3.62 3.30 3.62 3.93 4.09 4.09 4.09 4.25 4.41 4.57 4.57 4.72 4.25

2.42 2.52 2.53 2.46 2.60 2.81 2.67 2.79 2.78 2.90 3.05 3.16 3.10 3.28 3.42 3.60 3.68 3.71 3.66 3.83 4.01 4.07 4.23 4.25

5.63 6.26

5.06 5.35

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

03/30/07 03/31/07 04/01/07 04/02/07 04/03/07 04/04/07 04/05/07 04/06/07 04/07/07 04/08/07 04/09/07 04/10/07 04/11/07 04/12/07 04/13/07 04/14/07 04/15/07 04/16/07 04/17/07 04/18/07 04/19/07 04/20/07 04/21/07 04/22/07 04/23/07 04/24/07 04/25/07 04/26/07 04/27/07 04/28/07 04/29/07 04/30/07 05/01/07

12.57 12.88 13.19 13.35 12.57 12.73 14.44 15.71 15.39 15.23 14.60 11.64 11.33 12.88 13.97 13.66 13.19 14.13 13.66 11.17 11.48 13.97 13.51 13.51 15.56 16.66 16.66 16.51 18.27 19.74 19.58 19.91 19.91

10.85 12.01 12.36 12.22 11.54 11.57 12.33 13.54 14.23 14.23 12.90 10.70 9.98 11.20 11.96 12.31 11.76 12.13 11.84 9.17 9.00 11.36 12.16 12.35 12.99 14.33 14.96 14.47 15.49 17.12 17.95 17.68 17.94

12.38 12.54 12.85 11.61 9.43 9.74 11.30 11.76 10.99 9.89 9.12 8.96 9.43 9.43 10.37 9.43 10.52 10.37 9.43 8.65 10.21 10.68 9.74 9.27 11.92 11.45 11.61 11.30 12.23 12.69 11.61 12.54 12.85

10.41 11.27 11.40 10.35 7.81 8.57 9.02 9.89 9.76 8.68 8.23 7.46 7.54 8.28 8.12 8.35 8.73 8.37 8.16 7.17 7.83 8.51 8.36 8.36 9.32 9.49 9.66 9.66 9.86 10.42 9.95 10.24 10.52

12.03 9.65 12.03 10.37 12.03 10.43 10.94 9.37 8.92 7.05 9.08 7.77 10.94 8.27 11.25 8.92 10.17 8.67 8.77 7.79 8.16 7.37 8.46 6.79 8.92 6.83 8.92 7.46 9.86 7.37 8.92 7.49 9.86 7.91 9.86 7.56 9.23 7.41 7.69 6.42 9.86 7.28 9.86 7.72 9.23 7.59 8.31 7.53 11.10 8.55 10.79 8.58 11.10 8.75 10.79 8.69 11.41 8.91 11.87 9.37 10.32 8.84 11.72 9.24 11.56 9.48

230

11.54 11.39 11.23 9.90 8.51 8.51 10.37 10.68 9.59 8.19 7.89 8.19 8.51 8.66 9.43 8.51 9.43 9.43 8.66 6.81 9.43 9.12 8.66 7.58 10.53 10.22 10.68 10.22 10.84 11.15 9.74 10.84 10.99

8.79 9.39 9.51 8.54 6.54 7.21 7.70 8.15 7.90 7.18 6.78 6.29 6.36 6.90 6.83 6.94 7.33 7.00 6.91 5.95 6.85 7.13 7.05 6.97 7.95 7.86 8.04 7.94 8.18 8.53 8.04 8.42 8.64

10.70 10.39 11.01 9.15 8.07 8.07 9.46 9.77 8.84 7.46 7.30 7.92 7.76 8.07 8.69 7.92 8.84 8.69 8.38 6.37 8.69 8.84 8.22 7.14 9.61 9.46 9.77 9.31 9.92 10.08 8.84 9.77 9.92

8.11 8.50 8.86 7.87 6.15 6.69 7.09 7.37 7.14 6.51 6.33 5.99 6.02 6.45 6.37 6.48 6.79 6.53 6.50 5.77 6.59 6.78 6.73 6.58 7.39 7.28 7.42 7.30 7.55 7.77 7.40 7.71 7.88

6.26 6.26 6.26 5.79 5.95 5.79 6.11 6.26 6.11 5.63 5.48 5.48 5.95 5.48 5.95 6.11 5.95 5.95 6.11 5.79 6.11 6.42 6.57 5.95 6.11 6.57 6.57 6.57 6.88 6.88 6.57 6.73 6.73

5.52 5.72 5.77 5.31 5.43 5.57 5.66 5.72 5.55 5.30 5.35 5.31 5.49 5.32 5.52 5.68 5.60 5.67 5.73 5.62 5.84 6.02 6.09 5.92 5.98 6.13 6.23 6.21 6.35 6.41 6.37 6.43 6.52

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

05/02/07 05/03/07 05/04/07 05/05/07 05/06/07 05/07/07 05/08/07 05/09/07 05/10/07 05/11/07 05/12/07 05/13/07 05/14/07 05/15/07 05/16/07 05/17/07 05/18/07 05/19/07 05/20/07 05/21/07 05/22/07 05/23/07 05/24/07 05/25/07 05/26/07 05/27/07 05/28/07 05/29/07 05/30/07 05/31/07 06/01/07 06/02/07 06/03/07

19.08 15.07 15.23 15.07 15.87 18.76 20.56 21.21 21.38 20.88 21.71 20.56 19.08 20.07 21.21 22.38 22.04 21.54 20.23 17.62 17.14 18.27 20.07 20.23 20.72 20.39 19.41 20.39 21.38 22.72 23.58 23.92 25.31

16.50 13.83 13.19 12.94 13.41 15.58 17.64 19.05 19.23 18.96 19.49 18.28 16.88 17.53 18.68 19.92 20.05 20.07 18.12 15.59 14.58 15.66 17.68 18.46 18.92 19.09 17.49 17.75 18.84 20.13 21.14 21.82 23.09

11.45 10.99 11.45 11.76 12.07 13.32 13.63 13.78 13.01 12.85 13.63 13.16 13.01 13.78 14.09 14.09 14.09 13.94 12.69 11.92 11.92 13.63 13.94 14.25 14.41 14.57 13.94 14.72 15.36 15.67 15.99 16.15 16.63

9.43 9.20 9.26 9.40 9.72 10.69 11.17 11.45 11.18 10.98 11.32 11.13 10.80 11.30 11.64 11.79 11.94 11.95 10.96 10.66 10.49 11.21 11.90 12.10 12.51 12.57 12.16 12.28 12.89 13.29 13.60 13.72 14.40

9.86 10.32 10.94 11.25 11.41 12.49 12.81 12.96 12.18 12.03 12.81 12.18 12.18 12.81 13.12 13.12 13.12 13.12 10.94 11.41 11.56 13.12 13.27 13.73 13.58 13.58 13.27 13.88 14.51 14.82 14.98 14.98 15.61

231

8.32 8.42 8.46 8.61 8.91 9.70 10.00 10.26 9.92 9.80 10.17 10.00 9.75 10.22 10.48 10.61 10.73 10.80 9.89 9.76 9.68 10.38 10.90 11.16 11.44 11.46 11.13 11.29 11.77 12.09 12.34 12.43 13.06

8.66 9.90 10.37 10.68 10.84 11.77 12.08 12.23 11.30 11.30 11.92 11.46 11.46 12.08 12.23 12.39 12.23 12.39 10.37 10.84 11.15 12.54 12.70 12.86 12.86 12.86 12.70 13.32 13.78 14.09 14.24 14.09 14.72

7.57 7.82 7.88 8.04 8.32 8.95 9.16 9.37 9.06 8.98 9.33 9.21 9.05 9.48 9.67 9.77 9.86 9.95 9.23 9.16 9.20 9.82 10.24 10.39 10.60 10.70 10.41 10.62 11.05 11.29 11.50 11.62 12.14

7.76 9.31 9.61 9.77 9.92 10.54 10.70 10.85 10.39 10.23 10.70 10.54 10.54 11.01 11.01 11.32 11.16 11.32 10.08 10.23 10.70 11.62 11.62 11.93 11.93 12.08 11.78 12.39 12.71 12.86 13.17 13.02 13.32

7.08 7.42 7.47 7.64 7.82 8.27 8.40 8.59 8.35 8.30 8.59 8.55 8.47 8.82 8.94 9.06 9.11 9.23 8.78 8.78 8.87 9.30 9.58 9.71 9.88 10.03 9.80 10.03 10.37 10.53 10.72 10.81 11.24

6.57 6.88 6.88 7.04 7.19 7.04 7.19 7.35 7.35 7.50 7.50 7.50 7.66 7.81 7.97 7.97 8.12 8.28 8.12 8.28 8.43 8.43 8.74 8.74 8.89 8.89 9.05 9.36 9.36 9.36 9.67 9.83 9.83

6.48 6.61 6.69 6.83 6.88 6.91 7.05 7.15 7.14 7.16 7.28 7.38 7.45 7.62 7.70 7.74 7.81 7.95 8.00 8.03 8.14 8.24 8.37 8.46 8.57 8.69 8.72 8.93 9.08 9.14 9.31 9.46 9.57

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

06/04/07 06/05/07 06/06/07 06/07/07 06/08/07 06/09/07 06/10/07 06/11/07 06/12/07 06/13/07 06/14/07 06/15/07 06/16/07 06/17/07 06/18/07 06/19/07 06/20/07 06/21/07 06/22/07 06/23/07 06/24/07 06/25/07 06/26/07 06/27/07 06/28/07 06/29/07 06/30/07 07/01/07 07/02/07 07/03/07 07/04/07 07/05/07 07/06/07

24.27 21.38 17.46 17.78 20.23 20.56 19.58 18.43 20.56 21.38 21.38 21.38 21.54 19.91 20.39 21.38 21.54 23.23 23.58 22.55 21.54 20.39 20.88 22.04 23.41 23.92 22.89 23.41 22.55 23.41 24.44 24.96 24.27

22.20 19.08 15.47 15.46 17.41 18.73 17.89 16.50 18.31 19.37 19.82 19.56 19.88 18.45 18.50 19.17 20.08 20.81 21.58 20.88 19.88 18.81 18.72 19.82 21.28 21.96 21.20 21.21 21.07 21.18 22.16 22.82 22.86

15.52 13.63 12.07 14.25 15.67 15.67 14.57 15.67 16.47 15.52 15.67 16.15 16.47 15.52 15.99 16.63 16.47 17.11 17.11 16.79 16.63 15.99 16.79 17.27 17.43 17.27 17.27 17.58 16.79 17.74 18.07 18.23 17.58

13.73 12.24 11.33 12.07 13.07 13.57 12.77 13.18 14.02 13.92 13.64 13.79 14.14 13.59 13.73 14.19 14.39 14.63 14.81 14.74 14.46 14.18 14.36 14.92 15.21 15.28 15.19 15.19 15.07 15.38 15.68 15.86 15.76

13.58 12.18 11.10 13.42 14.98 14.98 13.12 14.98 15.77 14.98 14.98 15.61 15.77 14.98 15.46 16.09 15.77 16.41 16.41 16.24 15.93 15.61 16.24 16.57 16.72 16.72 16.72 16.88 16.24 17.04 17.36 17.52 17.04

232

12.36 11.21 10.58 11.44 12.25 12.68 11.92 12.53 13.20 13.00 12.94 13.13 13.43 12.96 13.13 13.53 13.69 13.92 14.06 14.04 13.79 13.57 13.81 14.26 14.48 14.55 14.52 14.53 14.38 14.72 14.98 15.12 15.02

12.70 11.30 10.53 13.17 14.24 14.56 12.08 14.40 15.19 14.40 14.40 15.03 15.19 14.56 15.03 15.51 15.19 15.83 15.83 15.67 15.51 15.19 15.83 15.99 16.14 16.14 16.14 16.31 15.67 16.62 16.78 16.94 16.62

11.53 10.64 10.15 11.03 11.63 12.03 11.35 12.00 12.54 12.32 12.37 12.57 12.85 12.46 12.66 13.01 13.15 13.35 13.46 13.47 13.30 13.13 13.38 13.74 13.94 13.98 13.98 14.01 13.88 14.21 14.43 14.54 14.45

12.08 10.85 10.39 12.55 13.17 13.63 11.32 13.63 14.25 13.48 13.63 14.09 14.25 13.79 14.25 14.56 14.41 14.72 14.87 14.72 14.72 14.41 15.03 15.19 15.35 15.19 15.35 15.51 14.87 15.67 15.98 15.98 15.98

10.83 10.27 9.96 10.73 11.09 11.44 10.83 11.55 11.93 11.73 11.85 12.07 12.32 12.04 12.26 12.53 12.64 12.81 12.91 12.95 12.87 12.78 12.99 13.25 13.41 13.44 13.49 13.53 13.46 13.71 13.90 13.98 13.92

9.83 9.98 9.98 10.14 10.29 10.61 10.45 10.76 10.92 11.07 11.07 11.22 11.38 11.53 11.69 11.84 11.84 12.00 12.00 12.16 12.16 12.31 12.47 12.47 12.62 12.62 12.62 12.78 12.78 12.93 13.09 13.09 13.09

9.68 9.78 9.87 10.06 10.16 10.32 10.38 10.55 10.70 10.76 10.90 11.06 11.19 11.25 11.42 11.54 11.62 11.72 11.84 11.92 12.01 12.08 12.17 12.28 12.35 12.43 12.49 12.59 12.64 12.71 12.83 12.89 12.94

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

07/07/07 07/08/07 07/09/07 07/10/07 07/11/07 07/12/07 07/13/07 07/14/07 07/15/07 07/16/07 07/17/07 07/18/07 07/19/07 07/20/07 07/21/07 07/22/07 07/23/07 07/24/07 07/25/07 07/26/07 07/27/07 07/28/07 07/29/07 07/30/07 07/31/07 08/01/07 08/02/07 08/03/07 08/04/07 08/05/07 08/06/07 08/07/07 08/08/07

24.44 24.27 24.27 24.44 24.78 23.92 23.92 24.92 24.94 23.98 23.93 24.44 23.64 23.30 23.35 24.17 23.35 22.54 22.94 23.45 24.97 24.82 24.12 23.18 23.26 23.67 22.80 23.69 24.24 23.09 21.99 22.56 22.87

22.63 22.51 22.39 22.55 23.00 22.65 22.55 22.85 23.23 22.69 22.32 22.73 22.14 21.62 21.70 22.18 21.99 21.05 21.59 21.62 22.91 23.24 22.85 21.97 21.54 21.79 21.69 21.55 22.26 21.21 20.41 20.70 20.96

17.91 17.91 18.23 18.23 18.17 17.20 17.68 18.98 18.33 17.84 18.66 18.82 18.66 18.66 17.68 19.14 17.68 17.52 18.17 19.46 19.78 19.78 19.14 18.98 19.62 19.78 18.49 20.18 20.02 18.88 19.37 19.69 19.86

15.87 15.90 15.95 16.09 16.13 15.84 16.18 16.50 16.48 16.27 16.72 16.67 16.60 16.51 16.22 16.85 16.39 16.48 16.83 17.23 17.65 17.60 17.36 17.40 17.60 17.61 16.96 17.79 18.13 17.46 17.44 17.72 17.76

17.21 17.36 17.52 17.68 17.52 16.57 17.21 18.17 17.68 16.88 18.01 18.01 18.01 18.01 17.04 18.49 16.88 17.04 17.68 18.81 19.13 19.13 18.49 18.33 18.97 19.13 17.21 19.62 19.46 18.33 18.97 19.29 19.46

233

15.17 15.19 15.26 15.37 15.37 15.10 15.43 15.78 15.69 15.49 16.02 15.97 15.89 15.85 15.61 16.21 15.77 15.89 16.12 16.54 16.93 16.88 16.64 16.70 16.93 16.91 16.23 17.21 17.37 16.78 16.89 17.13 17.20

16.78 16.78 16.94 17.10 17.10 16.14 16.78 17.74 17.10 16.31 17.58 17.58 17.42 17.58 16.62 18.06 16.46 16.62 17.42 18.38 18.71 18.71 17.90 17.90 18.55 18.71 16.62 19.20 19.04 17.90 18.38 19.04 19.04

14.62 14.63 14.73 14.83 14.83 14.62 14.89 15.26 15.16 14.96 15.45 15.47 15.40 15.39 15.19 15.74 15.31 15.48 15.70 16.10 16.40 16.36 16.16 16.24 16.45 16.42 15.79 16.78 16.86 16.35 16.54 16.76 16.84

15.98 15.98 16.14 16.29 16.14 15.67 16.14 16.77 16.46 15.82 16.77 16.77 16.61 16.77 16.14 17.24 16.14 16.29 16.93 17.56 17.88 17.88 17.40 17.24 17.88 17.88 16.14 18.36 18.36 17.56 18.20 18.52 18.52

14.09 14.13 14.24 14.31 14.35 14.23 14.41 14.74 14.65 14.54 14.93 14.99 14.96 14.98 14.86 15.29 14.96 15.17 15.32 15.68 15.83 15.87 15.77 15.84 16.03 16.02 15.53 16.37 16.40 16.02 16.25 16.45 16.55

13.24 13.24 13.40 13.40 13.56 13.56 13.71 13.71 13.86 13.86 14.02 14.17 14.33 14.33 14.33 14.48 14.48 14.64 14.80 14.80 14.96 14.96 15.12 15.28 15.28 15.44 15.44 15.44 15.59 15.76 15.76 15.91 16.07

13.02 13.10 13.21 13.27 13.39 13.43 13.50 13.60 13.70 13.77 13.86 13.95 14.06 14.14 14.15 14.30 14.34 14.46 14.60 14.64 14.76 14.84 14.91 15.01 15.10 15.18 15.22 15.36 15.47 15.51 15.59 15.74 15.87

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

08/09/07 08/10/07 08/11/07 08/12/07 08/13/07 08/14/07 08/15/07 08/16/07 08/17/07 08/18/07 08/19/07 08/20/07 08/21/07 08/22/07 08/23/07 08/24/07 08/25/07 08/26/07 08/27/07 08/28/07 08/29/07 08/30/07 08/31/07 09/01/07 09/02/07 09/03/07 09/04/07 09/05/07 09/06/07 09/07/07 09/08/07 09/09/07 09/10/07

23.33 23.04 22.71 23.23 23.18 22.97 22.51 22.97 22.90 22.85 21.80 19.39 21.63 21.87 21.92 21.94 22.32 22.47 21.49 21.27 21.72 22.99 22.80 23.38 23.55 23.09 22.59 20.63 20.27 20.84 19.70 18.99 18.82

21.37 21.48 20.96 21.18 21.30 21.06 20.85 21.29 21.24 21.14 19.37 18.25 19.52 20.24 20.20 20.16 20.40 20.75 20.09 19.66 19.83 20.76 21.74 21.63 21.96 21.54 21.21 19.21 18.45 18.99 18.38 17.60 17.23

21.94 21.01 21.13 21.51 22.08 21.80 20.67 19.53 21.08 21.08 20.89 21.03 21.46 21.53 20.75 20.56 20.89 21.46 22.23 22.49 22.75 22.32 21.96 19.98 19.72 20.41 19.29 18.60 18.58

21.02 19.55 19.46 19.98 20.28 20.08 18.59 17.99 19.16 19.53 19.28 19.28 19.63 20.00 19.35 18.99 19.11 19.91 20.96 20.86 21.20 20.79 20.63 18.18 17.74 18.64 17.95 17.23 16.96

20.18 19.86 20.35 20.51 20.51 19.86 19.69 20.67 20.67 20.84 19.69 20.02 20.67 20.35 20.35 20.67 20.84 20.67 20.18 20.35 20.67 20.51 20.67 21.50 21.17 21.01 20.35 19.04 20.02 20.18 19.37 18.72 19.21

18.08 18.22 18.13 18.50 18.45 18.29 18.19 19.01 18.93 18.73 17.75 18.04 18.86 18.68 18.61 18.70 18.97 19.02 18.66 18.52 18.74 19.15 19.56 19.50 19.76 19.35 19.24 17.57 18.20 18.53 17.99 17.48 17.58

19.62 19.46 19.94 19.94 20.11 19.46 19.46 20.43 20.27 20.43 18.65 19.78 20.43 20.11 20.11 20.43 20.59 20.43 19.94 20.11 20.43 20.11 20.43 21.09 20.76 20.59 19.78 18.33 19.78 19.94 18.81 18.65 18.97

234

17.46 17.61 17.58 17.85 17.85 17.60 17.62 18.40 18.29 18.16 17.09 17.68 18.38 18.15 18.09 18.20 18.40 18.44 18.14 18.04 18.25 18.52 18.93 18.92 19.08 18.71 18.55 17.06 17.80 18.04 17.49 17.07 17.22

19.20 19.20 19.69 19.69 19.85 19.20 19.20 20.01 19.85 20.17 18.06 19.53 20.17 19.85 20.01 20.17 20.33 20.17 19.85 20.01 20.33 19.85 20.17 20.66 20.49 20.33 19.53 17.74 19.78 19.94 18.81 18.65 18.97

17.07 17.20 17.23 17.45 17.46 17.21 17.31 17.98 17.88 17.81 16.82 17.49 18.05 17.83 17.80 17.89 18.05 18.08 17.83 17.78 17.99 18.11 18.47 18.51 18.62 18.29 18.11 16.88 17.80 18.04 17.49 17.07 17.22

18.52 18.52 19.01 19.17 19.17 18.68 18.84 19.49 19.33 19.66 17.56 19.33 19.49 19.49 19.49 19.82 19.82 19.66 19.49 19.49 19.82 19.33 19.82 20.31 19.98 19.98 19.33 17.40 19.49 19.49 18.84 18.68 19.17

16.71 16.84 16.93 17.06 17.13 16.95 17.08 17.56 17.51 17.52 16.76 17.41 17.76 17.60 17.59 17.67 17.73 17.77 17.62 17.59 17.76 17.76 18.03 18.20 18.16 17.93 17.76 16.80 17.52 17.59 17.17 16.98 17.18

16.23 16.23 16.39 16.54 16.54 16.71 16.86 16.86 16.86 17.02 16.86 17.18 17.18 17.18 17.18 17.18 17.34 17.34 17.34 17.34 17.34 17.34 17.34 17.34 17.34 17.34 17.18 17.02 17.34 17.34 17.18 17.18 17.50

15.94 16.06 16.17 16.26 16.36 16.45 16.57 16.65 16.73 16.82 16.81 16.94 16.96 16.97 16.99 16.99 17.03 17.08 17.09 17.09 17.10 17.08 17.09 17.12 17.07 17.00 16.96 16.90 16.98 17.00 16.96 16.96 17.13

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

09/11/07 09/12/07 09/13/07 09/14/07 09/15/07 09/16/07 09/17/07 09/18/07 09/19/07 09/20/07 09/21/07 09/22/07 09/23/07 09/24/07 09/25/07 09/26/07 09/27/07 09/28/07 09/29/07 09/30/07 10/01/07 10/02/07 10/03/07 10/04/07 10/05/07 10/06/07 10/07/07 10/08/07 10/09/07 10/10/07 10/11/07 10/12/07 10/13/07

19.15 19.41 19.96 20.25 20.25 19.58 18.75 17.70 16.73 17.37 17.94 17.15 15.75 16.20 16.37 16.61 16.94 16.37 14.58 13.83 14.51 14.65 14.53 14.84 13.88 12.92 14.46 15.25 15.84 15.32 13.33 13.50 14.60

17.42 17.75 18.34 18.90 18.70 18.19 17.57 16.28 15.52 15.82 16.38 15.89 15.26 14.94 14.95 15.15 15.47 15.36 13.69 12.92 13.47 13.62 14.05 13.72 12.97 11.84 12.85 14.00 14.52 14.11 12.61 12.96 13.35

19.01 19.32 19.53 19.13 19.70 19.08 18.65 17.65 16.99 17.42 17.84 17.13 15.80 16.32 16.42 16.63 16.96 16.32 14.55 14.07 14.70 14.79 14.82 14.77 13.93 12.92 14.39 15.39 15.94 15.32 13.83 13.35 14.70

17.27 17.61 18.03 18.32 18.25 17.79 17.43 15.94 15.62 15.86 16.33 15.92 15.26 14.96 14.91 15.12 15.40 15.46 13.21 12.76 13.75 13.61 14.24 13.81 12.86 11.85 12.83 13.99 14.57 14.23 12.87 12.89 13.39

19.53 19.69 19.86 19.69 19.69 19.37 18.55 17.74 17.91 18.39 18.72 18.07 16.94 17.27 17.43 17.58 18.07 17.58 15.67 15.67 15.36 15.99 15.67 15.19 14.72 14.41 15.67 16.47 16.79 15.99 14.88 14.41 15.67

18.08 18.21 18.46 18.70 18.49 18.13 17.67 16.46 16.66 17.12 17.34 17.09 16.32 15.94 16.18 16.31 16.61 16.38 14.76 14.48 14.79 14.79 15.12 14.58 13.93 13.18 13.80 15.01 15.37 14.95 13.68 13.81 14.20

19.46 19.62 19.62 19.46 19.29 19.13 18.17 17.36 17.84 18.33 18.65 17.68 16.57 17.21 17.36 17.52 17.84 17.04 15.29 15.46 15.14 15.93 15.46 15.14 14.51 13.88 15.14 16.09 16.24 15.77 14.35 13.88 15.14

235

17.70 17.80 18.02 18.25 18.01 17.65 17.22 16.04 16.45 16.88 17.06 16.71 15.98 15.72 15.93 16.05 16.31 15.96 14.41 14.23 14.53 14.69 14.89 14.43 13.79 12.82 13.49 14.63 14.91 14.32 13.10 13.20 13.78

19.46 19.62 19.62 19.46 19.29 19.13 18.17 17.36 17.84 18.33 18.65 17.68 16.57 17.21 17.36 17.52 17.84 17.04 15.29 15.46 15.12 15.74 15.27 14.80 14.18 13.56 15.12 15.74 15.91 14.96 13.87 13.26 14.64

17.70 17.80 18.02 18.25 18.01 17.65 17.22 16.04 16.45 16.88 17.06 16.71 15.98 15.72 15.93 16.05 16.31 15.96 14.41 14.23 14.50 14.58 14.68 14.27 13.55 12.42 13.18 14.28 14.41 13.63 12.60 12.62 13.32

19.33 19.49 19.49 19.33 19.17 19.01 18.52 16.93 18.36 18.68 18.84 17.56 16.77 17.88 17.88 17.88 17.88 16.93 15.67 15.67 15.67 15.98 15.67 15.19 14.72 14.72 15.57 16.36 16.52 14.31 14.31 13.54 15.57

17.44 17.54 17.65 17.79 17.59 17.36 17.10 16.21 16.72 16.96 17.08 16.64 16.13 16.11 16.13 16.15 16.30 15.79 14.71 14.54 14.78 14.87 14.94 14.57 13.96 13.03 13.69 14.43 14.42 13.68 12.87 12.93 13.60

17.50 17.50 17.50 17.34 17.34 17.50 17.34 17.18 17.18 17.18

17.16 17.25 17.23 17.17 17.15 17.20 17.09 17.04 16.94 16.93

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

10/14/07 10/15/07 10/16/07 10/17/07 10/18/07 10/19/07 10/20/07 10/21/07 10/22/07 10/23/07 10/24/07 10/25/07 10/26/07 10/27/07 10/28/07 10/29/07 10/30/07 10/31/07 11/01/07 11/02/07 11/03/07 11/04/07 11/05/07 11/06/07 11/07/07 11/08/07 11/09/07 11/10/07 11/11/07 11/12/07 11/13/07 11/14/07 11/15/07

14.79 14.07

13.58 13.11

14.89 15.03 14.98 14.24 12.58 12.17 12.22 12.58 12.87 13.26 14.00 13.40 12.17 11.71 11.66 12.05

13.57 13.80 14.17 13.37 11.14 11.49 11.65 11.48 11.73 12.01 12.74 12.59 11.07 10.69 10.65 10.88

15.99 15.83 15.52 14.41 13.16 12.85 13.16 13.32 13.63 14.09 14.57 14.09 12.85 13.16 13.16 13.63 14.09 13.01 12.38 12.07 12.23 12.07 12.07 11.76 11.61 11.76 11.61 11.45 12.07 10.83 10.68 9.74 9.89

14.53 14.72 14.57 13.71 11.83 12.25 12.24 12.00 12.43 12.81 13.37 13.14 12.03 11.84 11.99 12.70 13.35 12.01 11.53 11.15 10.95 10.90 10.94 10.91 10.82 10.93 10.88 10.79 11.13 9.63 9.96 8.83 8.90

15.46 15.29 14.66 13.88 12.18 12.18 12.49 12.65 13.27 13.73 14.19 13.42 12.18 12.03 12.34 12.81 13.42 12.03 11.56 11.10 11.10 10.94 10.94 10.94 11.10 11.25 10.79 10.48 10.94 9.54 9.86 8.77 8.92

236

14.06 14.19 13.96 13.16 11.06 11.60 11.67 11.44 11.96 12.29 12.86 12.52 11.30 10.84 11.10 11.82 12.54 10.96 10.47 10.02 9.85 9.75 9.74 9.86 9.87 10.09 9.91 9.84 10.17 8.51 8.99 7.83 7.87

15.12 14.96 14.18 13.26 11.54 11.70 11.70 12.17 12.79 13.41 13.71 12.94 11.39 11.54 11.86 12.48 12.94 11.39 11.23 10.62 10.62 10.47 10.47 10.47 10.47 10.62 9.84 9.69 10.16 8.46 9.07 7.84 7.99

13.59 13.63 13.40 12.64 10.36 10.99 11.07 10.94 11.48 11.76 12.27 11.90 10.69 10.30 10.60 11.30 11.95 10.38 9.93 9.48 9.32 9.22 9.20 9.32 9.26 9.39 9.12 9.10 9.41 7.67 8.22 7.10 7.07

15.89 14.93 14.46 13.38 11.37 11.84 12.30 13.08 11.37

13.83 13.70 13.50 12.74 10.65 11.19 11.39 11.39 11.22

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

11/16/07 11/17/07 11/18/07 11/19/07 11/20/07 11/21/07 11/22/07 11/23/07 11/24/07 11/25/07 11/26/07 11/27/07 11/28/07 11/29/07 11/30/07 12/01/07 12/02/07 12/03/07 12/04/07 12/05/07 12/06/07 12/07/07 12/08/07 12/09/07 12/10/07 12/11/07 12/12/07 12/13/07 12/14/07 12/15/07 12/16/07 12/17/07 12/18/07

10.68 11.92 12.69 12.38 10.21 8.65 8.50 7.57 7.88 8.50 7.88 8.19 7.72 8.03 7.57 7.10 7.10 8.50 9.74 9.27 8.96 8.96 8.50 6.94 6.63 5.69 5.54 6.17 6.01 6.48 7.26 7.41 7.41

9.93 11.01 11.97 11.18 9.10 7.75 7.24 6.60 6.68 7.47 7.02 7.43 7.03 7.35 6.54 6.04 6.12 7.38 8.85 8.62 8.47 8.32 7.47 6.03 5.82 4.72 4.77 5.31 5.02 5.40 5.97 6.54 6.59

9.86 9.08 11.25 10.27 11.87 11.17 11.25 10.10 8.77 7.96 7.38 6.46 7.07 6.06 6.44 5.51 6.76 5.58 7.38 6.44 6.60 5.86 7.22 6.40 6.60 5.95 6.91 6.13 6.13 5.31 5.51 4.71 5.51 4.83 7.22 6.25 8.77 7.92 8.00 7.49 7.84 7.18 7.53 7.03 6.76 6.06 5.51 4.51 4.88 4.31 3.79 3.07 4.26 3.32 4.73 3.92 4.42 3.45 4.57 3.90 5.67 4.67 6.13 5.26 5.67 5.30

237

9.07 10.47 10.93 10.16 7.69 6.29 6.14 5.67 5.98 6.61 5.83 6.29 5.83 5.98 5.36 4.74 4.58 6.29 7.84 7.23 6.92 6.45 5.83 4.43 3.96 2.71 3.49 3.96 3.65 3.65 4.74 5.21 4.74

8.41 9.57 10.34 9.13 7.08 5.57 5.35 4.82 4.95 5.75 5.13 5.62 5.22 5.27 4.59 3.97 4.02 5.45 7.13 6.66 6.31 6.20 5.24 3.73 3.51 2.26 2.62 3.25 2.78 3.13 3.98 4.48 4.47

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date

BR at Parma BR at Middleton

BR at Eagle

February 2009

Br at Glenwood BR at Veterans Parkway

BR at Marden Bridge

BR at Lucky Peak

Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average Maximum Average

12/19/07 12/20/07 12/21/07 12/22/07 12/23/07 12/24/07 12/25/07 12/26/07 12/27/07 12/28/07 12/29/07 12/30/07 12/31/07 01/01/08 01/02/08 01/03/08

7.10 7.41 6.48 5.69 6.01 6.79 5.69 5.69 5.54 5.07 6.17 6.48 5.54 4.60 4.44 4.60

6.63 6.62 5.52 4.58 5.01 5.70 4.76 4.69 4.56 4.29 4.94 5.33 4.42 3.44 3.41 3.49

5.67 5.82 4.73 3.63 4.10 5.36 4.26 3.79 3.63 3.48 4.57 4.88 3.63 2.69 2.69 2.69

BR = Boise River

238

5.30 5.35 3.94 2.94 3.44 4.50 3.37 3.13 3.04 2.73 3.53 4.03 2.92 1.84 1.71 1.94

4.89 5.05 3.65 2.71 3.18 4.43 3.49 2.86 2.86 2.39 3.65 3.96 2.71 1.76 1.60 1.60

4.47 4.56 3.08 2.14 2.64 3.80 2.66 2.35 2.27 1.90 2.72 3.25 2.17 1.09 0.89 1.13

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table C-10. Geomean Bacteria Data from Lower Boise River, 2003-2008, provided by the City of Boise.

Date 3/27/2003 4/3/2003 4/10/2003 4/17/2003 4/24/2003 5/1/2003 5/8/2003 5/15/2003 5/22/2003 5/29/2003 6/5/2003 6/12/2003 6/19/2003 6/26/2003 7/3/2003 7/10/2003 7/17/2003 7/24/2003 7/31/2003 8/7/2003 8/14/2003 8/21/2003 8/28/2003 9/4/2003 9/11/2003 9/18/2003

AU 011a_06

AU 011a_06

AU 011a_06

AU 011a_06

AU 005_06

Boise River at Eckert Road

Boise River at Marden Bridge

Boise River at Veterans Parkway

Boise River at Glenwood

Boise River at Eagle

E. coli cfu/100 mL Geomean 4.7 4 3.3 3.4 3.7 3.3 1.3 3.1 7.3 4.4 4.0 4.8 2.7 4.3 2.7 5.0 7.7 11.0 12.0 9.3 2.3 7.2 5.7 6.1 129.7 4.7 3.3 2.2 3.3 2.4 1.0 2.0 1.7 2.5 2.7 3.2 5.7 3.6 1.3 4.0 2.7 6.0 6.7 6.7 4.7 6.2 9.3 6.4 10.3 6.2 4.7 6.5

E. coli cfu/100 mL Geomean 15.3 7.3 10.3 6.4 4.0 7.1 9.0 7.7 3.7 8.6 7.7 11.3 17.3 12.6 6.3 11.4 15.0 28.7 14.3 23.9 13.7 21.8 10.3 19.4 643.3 19.3 6.0 8.3 9.0 8.5 7.7 8.1 10.0 7.3 9.3 8.6 7.0 8.5 7.0 9.6 4.7 11.4 22.0 15.6 8.7 15.5 13.0 17.2 17.0 16.6 22.0 14.2

E. coli cfu/100 mL Geomean 34.3 22.3 25.7 24.0 14.0 23.6 15.3 27.8 29.0 33.4 49.7 34.7 23.7 29.9 32.0 29.8 38.0 47.7 35.3 42.7 23.3 37.0 23.3 41.1 339.0 42.4 21.7 24.9 17.3 24.0 39.7 25.8 27.0 22.9 23.7 22.7 18.0 22.5 25.0 27.6 22.0 32.2 25.7 37.3 22.7 41.9 49.7 48.6 54.7 54.0 46.0 53.3

239

E. coli cfu/100 mL Geomean 28.0 29.6 37.0 32.5 30.0 32.4 25.3 32.3 29.0 33.4 44.7 36.2 36.3 36.2 29.7 36.4 29.7 46.2 43.3 42.6 45.0 36.5 37.3 34.6 97.7 32.7 19.7 26.1 20.0 30.3 34.7 36.0 28.0 39.7 32.0 45.2 41.3 47.1 47.0 53.4 56.7 54.5 53.7 54.8 39.3 48.1 77.0 49.2 52.0 52.3 58.3 52.5

E. coli cfu/100 mL Geomean 59.0 30.5 36.7 25.9 24.7 23.3 22.7 22.6 22.0 22.8 26.0 25.3 21.3 27.3 21.3 30.7 23.7 39.8 37.0 42.7 38.0 41.4 38.7 39.4 78.0 37.2 33.3 32.2 32.0 32.7 29.7 32.1 29.0 32.3 38.0 34.6 36.0 37.1 29.0 41.2 30.7 48.4 41.0 52.2 53.7 55.6 61.0 56.9 64.7 58.4 44.7 57.1

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date 9/25/2003 10/2/2003 10/9/2003 10/16/2003 10/23/2003 10/30/2003 11/6/2003 11/13/2003 11/20/2003 11/24/2003 12/4/2003 12/11/2003 12/16/2003 12/22/2003 12/29/2003 1/8/2004 1/15/2004 1/22/2004 1/29/2004 2/5/2004 2/12/2004 2/19/2004 2/26/2004 3/4/2004 3/11/2004 3/18/2004 3/29/2004 4/5/2004

February 2009

AU 011a_06

AU 011a_06

AU 011a_06

AU 011a_06

AU 005_06

Boise River at Eckert Road

Boise River at Marden Bridge

Boise River at Veterans Parkway

Boise River at Glenwood

Boise River at Eagle

E. coli cfu/100 mL Geomean 4.3 7.3 5.7 8.4 7.7 9.2 13.0 8.8 8.3 7.4 8.7 8.3 9.3 6.7 6.0 6.4 5.7 5.4 14.0 4.5 3.0 3.6 7.3 4.6 2.7 4.0 2.3 5.2 4.7 6.8 10.0 6.1 3.7 6.1 9.3 6.8 9.3 4.8 2.7 3.8 10.0 4.8 6.3 4.0 1.7 4.0 2.7 5.3 9.3 5.0 4.0 4.0 6.0 3.5 7.0 3.5

E. coli cfu/100 mL Geomean 21.3 13.1 14.7 11.7 10.7 11.8 8.0 11.8 14.3 12.1 12.3 13.0 15.0 11.0 10.7 7.8 9.3 6.0 20.0 5.0 5.3 4.2 2.7 6.8 3.0 9.9 3.7 13.0 8.7 21.6 58.3 20.1 17.0 13.9 12.0 10.9 45.7 8.6 6.0 5.7 9.3 6.4 5.0 6.6 3.7 8.5 5.7 11.5 11.0 12.3 11.0 11.5 18.0 9.8 16.0 9.1

E. coli cfu/100 mL Geomean 45.7 63.2 47.7 74.3 84.0 116.8 51.0 120.1 108.0 114.0 102.7 117.7 456.7 89.4 96.7 47.7 39.3 35.0 126.7 30.7 26.0 22.9 19.7 26.2 20.7 29.4 20.3 34.8 29.3 46.8 51.0 47.5 35.0 46.5 47.7 42.1 90.3 37.8 31.3 30.4 46.0 27.3 21.3 24.7 27.7 26.1 30.7 32.2 18.3 30.7 27.7 31.2 28.0 28.3 80.0 27.0

240

E. coli cfu/100 mL Geomean 28.0 57.1 44.0 69.2 105.0 94.3 53.0 89.7 88.7 79.5 73.0 76.6 206.7 50.7 82.0 33.2 29.0 24.8 73.3 24.9 9.3 21.1 24.7 29.8 19.0 35.0 29.7 41.3 32.0 48.1 53.0 48.7 54.7 41.1 43.7 36.6 63.3 35.6 34.3 28.4 22.7 23.7 30.7 23.9 38.0 23.2 20.3 25.9 14.0 24.0 23.7 26.9 26.0 28.3 66.0 31.9

E. coli cfu/100 mL Geomean 56.3 66.9 60.3 67.0 69.0 72.0 58.0 67.2 98.7 62.8 56.7 50.0 86.3 41.4 49.0 34.2 41.3 31.4 31.7 30.2 22.0 34.1 33.3 40.5 32.0 49.5 33.7 50.7 58.7 62.9 51.7 52.0 91.3 36.1 36.0 28.8 98.7 30.7 22.7 27.3 8.3 29.2 29.7 36.3 49.7 35.9 54.7 30.2 31.7 24.2 24.7 26.8 28.0 29.4 21.0 30.4

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

AU 011a_06

AU 011a_06

AU 011a_06

AU 011a_06

AU 005_06

Boise River at Eckert Road

Boise River at Marden Bridge

Boise River at Veterans Parkway

Boise River at Glenwood

Boise River at Eagle

Date 4/13/2004 4/19/2004 4/26/2004 5/3/2004 5/11/2004 5/17/2004 5/24/2004 6/1/2004 6/8/2004 6/14/2004 6/21/2004 6/28/2004 7/6/2004 7/12/2004 7/19/2004 7/26/2004 8/2/2004 8/10/2004 8/16/2004 8/23/2004 8/30/2004 9/7/2004 9/14/2004 9/20/2004 9/27/2004

E. coli cfu/100 mL Geomean 2.0 5.0 3.0 5.0 2.0 5.6 6.0 6.7 45.0 6.9 2.0 4.8 5.0 5.2 5.0 5.4 7.0 4.8 7.0 8.4 3.0 7.5 6.0 8.6 3.0 8.6 110.0 8.6 4.0 5.5 6.0 9.2 6.0 15.5 3.0 23.4 12.0 38.5 50.0 43.8 83.0 35.7 47.0 23.4 36.0 38.5 23.0 43.8 18.0 35.7

E. coli cfu/100 mL Geomean 8.0 12.5 8.0 13.1 5.0 12.7 12.0 14.9 80.0 14.9 10.0 9.6 7.0 8.7 11.0 9.5 12.0 9.5 9.0 8.3 6.0 8.8 11.0 9.5 11.0 9.5 6.0 9.5 12.0 10.3 9.0 14.1 11.0 15.1 11.0 14.2 9.0 16.0 56.0 16.9 13.0 11.5 8.0 14.2 20.0 16.0 12.0 16.9 8.0 11.5

E. coli cfu/100 mL Geomean 24.0 31.0 20.0 33.5 17.0 27.9 22.0 34.7 160.0 35.0 35.0 25.0 8.0 25.5 51.0 34.4 23.0 28.8 30.0 28.3 38.0 28.3 36.0 25.1 21.0 20.8 21.0 20.6 30.0 21.0 21.0 26.7 14.0 32.6 20.0 39.8 23.0 41.6 100.0 42.6 57.0 42.9 38.0 39.8 25.0 41.6 26.0 42.6 103.0 42.9

E. coli cfu/100 mL Geomean 14.0 31.3 25.0 33.7 30.0 37.3 48.0 37.1 60.0 35.2 20.0 33.7 42.0 39.2 29.0 50.9 37.0 51.2 48.0 50.9 43.0 56.7 154.0 54.1 30.0 36.7 36.0 37.8 82.0 38.6 34.0 43.0 22.0 49.9 35.0 52.4 40.0 49.0 140.0 51.6 72.0 42.7 28.0 52.4 25.0 49.0 52.0 51.6 54.0 42.7

E. coli cfu/100 mL Geomean 18.0 35.5 53.0 37.3 39.0 30.1 33.0 26.8 46.0 25.6 23.0 23.5 18.0 24.7 22.0 31.9 26.0 34.4 30.0 37.6 30.0 42.8 64.0 41.6 32.0 39.3 41.0 37.7 57.0 36.7 26.0 44.3 48.0 51.8 26.0 50.2 36.0 51.7 146.0 54.5 57.0 45.9 41.0 50.2 30.0 51.7 47.0 54.5 62.0 45.9

% Exceeds

0.0

0.0

0.0

0.0

0.0

241

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Date 8/23/2005 8/30/2005 9/6/2005 9/13/2005 9/20/2005 9/27/2005 10/3/2005 10/11/2005 10/18/2005 10/24/2005 11/1/2005 11/8/2005 11/15/2005 11/21/2005 11/29/2005 12/6/2005 12/13/2005 12/19/2005 12/27/2005

February 2009

AU 005_06

Au 005_06

AU 001_06

Boise River at Middleton Bridge

Boise River near Caldwell

Boise River near Parma

E. coli cfu/100 mL Geomean 132 221 220 245 140 199 76 149 1700 126 220 48 79 52 33 48 33 66 14 72 330 92 49 81 170 69 49 58 49 66 170 81 22 69 70 58 100 66

E. coli cfu/100 mL Geomean 140 80 360 62 330 64 33 42 6 46 40 82 410 135 41 92 49 88 112 113 490 98 60 62 33 51 170 58 56 79 49 62 23 51 60 58 790 79

E. coli cfu/100 mL Geomean 240 130 79 117 90 167 170 179 130 145 140 109 460 97 130 66 58 55 31 67 79 125 70 131 49 147 160 161 700 245 100 131 124 147 79 161 1300 245

% Exceeds 26.0 AU = assessment unit; cfu = colony-forming unit

5.0

63.0

242

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table C-11. Water discharge and temperature data collection locations and data file quality assurance annotation for Lower Boise River Mainstem Tributary Temperature Analysis Data Summary and Technical Report, June 2005. Provided by the City of Boise, January 2009. Temperature collection site location Boise River at Notus Boise River at Caldwell Conway Gulch Dixie Slough Fifteen Mile Creek Indian Creek Mason Creek Mill Slough Willow Creek Temperature data files (February 2004 to October 2004) Boise_Notus_up_1.xls

Latitude 43.71953 43.67806 43.72667 43.73083 43.68734 43.67385 43.6835 43.70111 43.70667

Longitude -116.79806 -116.698056 -116.80333 -116.88833 -116.59035 -116.70142 -116.66733 -116.62222 -116.62972

Notes

Boise_Notus_dwn_1.xls Caldwell_up1.xls

sensor pulled out of water on 9/18/04

Caldwell_dwn.xls

missing 3/21 to 3/24/2004 sensor out of water

Conway_up_1.xls Dixie_up_1.xls Dixie_dwn_1.xls Fifteenmile_up_1.xls Fifteenmile_dwn_1.xls Indian_up.xls Indian_dwn.xls Mason_up_1.xls

missing 7/11 to 7/30/2004 sensor out of water

Mason_dwn.xls Temperature data files (February 2004 to October 2004)

missing 15:00 to 21:00 on 3/24/04, checked and relaunched

Notes

243

Lower Boise River 5-year Subbasin Assessment and TMDL Review Mill_up.xls Mill_dwn_1.xls

February 2009

missing 3/24 to 6/24/04, sensor taken

Willow_up_1.xls

missing 3:00 to 16:00 on 8/8/04; 3/24 to 4/5/2004 sensor may have been pulled out of water

Willow_dwn_1.xls

missing 2/17 to 3/24/2004, sensor pulled out; from approx. 4/30 to 6/25/2004 sensor buried under 1 ft. of coarse sand

Table C-12. Daily average discharge (Q) data used to create Lower Boise River Mainstem Tributary Temperature Analysis Data Summary and Technical Report, June 2005. Data reported in cubic feet per second (cfs), provided by the City of Boise, January 2009. Conway 2004 SiteID, Year, Day 13212550F2003274 13212550F2003275 13212550F2003276 13212550F2003277 13212550F2003278 13212550F2003279 13212550F2003280 13212550F2003281 13212550F2003282 13212550F2003283 13212550F2003284 13212550F2003285 13212550F2003286 13212550F2003287 13212550F2003288 13212550F2003289 13212550F2003290 13212550F2003291

Q 45.5 45 44.5 44 43.5 43 40.1 37.3 34.4 31.6 28.7 25.9 23 24.3 25.6 26.9 28.1 29.4

Dixie Drain 2004 SiteID, Year, Day Q 13212890F2003274 232.3 13212890F2003275 228.7 13212890F2003276 225 13212890F2003277 221.3 13212890F2003278 217.7 13212890F2003279 214 13212890F2003280 211 13212890F2003281 208 13212890F2003282 205 13212890F2003283 202 13212890F2003284 199 13212890F2003285 196 13212890F2003286 193 13212890F2003287 190.2 13212890F2003288 187.3 13212890F2003289 184.5 13212890F2003290 181.7 13212890F2003291 178.8

Fivemile 2004 SiteID, Year, Day 13210810F2003274 13210810F2003275 13210810F2003276 13210810F2003277 13210810F2003278 13210810F2003279 13210810F2003280 13210810F2003281 13210810F2003282 13210810F2003283 13210810F2003284 13210810F2003285 13210810F2003286 13210810F2003287 13210810F2003288 13210810F2003289 13210810F2003290 13210810F2003291

244

Q 134.8 133.7 132.5 131.3 130.2 129 126.5 124 121.5 119 116.5 114 113 112 111 110 109 108

Indian Creek 2004 SiteID, Year, Day Q 13211445F2003274 76.5 13211445F2003275 74 13211445F2003276 71.5 13211445F2003277 69 13211445F2003278 66.5 13211445F2003279 64 13211445F2003280 66.1 13211445F2003281 68.3 13211445F2003282 70.4 13211445F2003283 72.6 13211445F2003284 74.7 13211445F2003285 76.9 13211445F2003286 79 13211445F2003287 79.4 13211445F2003288 79.9 13211445F2003289 80.3 13211445F2003290 80.7 13211445F2003291 81.1

Mason Creek 2004 SiteID, Year, Day Q 13210849F2003274 17 13210849F2003275 17 13210849F2003276 17 13210849F2003277 17 13210849F2003278 17 13210849F2003279 17 13210849F2003280 16.7 13210849F2003281 16.4 13210849F2003282 16.1 13210849F2003283 15.9 13210849F2003284 15.6 13210849F2003285 15.3 13210849F2003286 15 13210849F2003287 14.2 13210849F2003288 13.3 13210849F2003289 12.5 13210849F2003290 11.7 13210849F2003291 10.8

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Conway 2004 SiteID, Year, Day 13212550F2003292 13212550F2003293 13212550F2003294 13212550F2003295 13212550F2003296 13212550F2003297 13212550F2003298 13212550F2003299 13212550F2003300 13212550F2003301 13212550F2003302 13212550F2003303 13212550F2003304 13212550F2004092 13212550F2004093 13212550F2004094 13212550F2004095 13212550F2004096 13212550F2004097 13212550F2004098 13212550F2004099 13212550F2004100 13212550F2004101 13212550F2004102 13212550F2004103 13212550F2004104 13212550F2004105

Q 30.7 32 31 30 29 28 27 26 25 25 25 25 25 6 6 6 6 6 10.7 15.4 20.1 24.9 29.6 34.3 39 40 41

Dixie Drain 2004 SiteID, Year, Day Q 13212890F2003292 176 13212890F2003293 169.9 13212890F2003294 163.8 13212890F2003295 157.6 13212890F2003296 151.5 13212890F2003297 145.4 13212890F2003298 139.3 13212890F2003299 133.1 13212890F2003300 127 13212890F2003301 127 13212890F2003302 127 13212890F2003303 127 13212890F2003304 127 13212890F2004092 57 13212890F2004093 57 13212890F2004094 57 13212890F2004095 57 13212890F2004096 57 13212890F2004097 61.1 13212890F2004098 65.3 13212890F2004099 69.4 13212890F2004100 73.6 13212890F2004101 77.7 13212890F2004102 81.9 13212890F2004103 86 13212890F2004104 89 13212890F2004105 92

Fivemile 2004 SiteID, Year, Day 13210810F2003292 13210810F2003293 13210810F2003294 13210810F2003295 13210810F2003296 13210810F2003297 13210810F2003298 13210810F2003299 13210810F2003300 13210810F2003301 13210810F2003302 13210810F2003303 13210810F2003304 13210810F2004092 13210810F2004093 13210810F2004094 13210810F2004095 13210810F2004096 13210810F2004097 13210810F2004098 13210810F2004099 13210810F2004100 13210810F2004101 13210810F2004102 13210810F2004103 13210810F2004104 13210810F2004105

245

February 2009

Q 107 106 97.6 89.1 80.7 72.3 63.9 55.4 47 47 47 47 47 31 31 31 31 31 35.7 40.4 45.1 49.9 54.6 59.3 64 68.1 72.3

Indian Creek 2004 SiteID, Year, Day Q 13211445F2003292 81.6 13211445F2003293 82 13211445F2003294 78.6 13211445F2003295 75.1 13211445F2003296 71.7 13211445F2003297 68.3 13211445F2003298 64.9 13211445F2003299 61.4 13211445F2003300 58 13211445F2003301 58 13211445F2003302 58 13211445F2003303 58 13211445F2003304 58 13211445F2004092 27 13211445F2004093 27 13211445F2004094 27 13211445F2004095 27 13211445F2004096 27 13211445F2004097 32.3 13211445F2004098 37.6 13211445F2004099 42.9 13211445F2004100 48.1 13211445F2004101 53.4 13211445F2004102 58.7 13211445F2004103 64 13211445F2004104 68 13211445F2004105 72

Mason Creek 2004 SiteID, Year, Day Q 13210849F2003292 10 13210849F2003293 9.6 13210849F2003294 9.3 13210849F2003295 8.9 13210849F2003296 8.5 13210849F2003297 8.1 13210849F2003298 7.8 13210849F2003299 7.4 13210849F2003300 7 13210849F2003301 7 13210849F2003302 7 13210849F2003303 7 13210849F2003304 7 13210849F2004092 5 13210849F2004093 5 13210849F2004094 5 13210849F2004095 5 13210849F2004096 5 13210849F2004097 6.1 13210849F2004098 7.3 13210849F2004099 8.4 13210849F2004100 9.6 13210849F2004101 10.7 13210849F2004102 11.9 13210849F2004103 13 13210849F2004104 13.7 13210849F2004105 14.4

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Conway 2004 SiteID, Year, Day 13212550F2004106 13212550F2004107 13212550F2004108 13212550F2004109 13212550F2004110 13212550F2004111 13212550F2004112 13212550F2004113 13212550F2004114 13212550F2004115 13212550F2004116 13212550F2004117 13212550F2004118 13212550F2004119 13212550F2004120 13212550F2004121 13212550F2004122 13212550F2004123 13212550F2004124 13212550F2004125 13212550F2004126 13212550F2004127 13212550F2004128 13212550F2004129 13212550F2004130 13212550F2004131 13212550F2004132

Q 42 43 44 45 46 47.6 49.1 50.7 52.3 53.9 55.4 57 57 57.7 58.3 59 59.7 60.3 61 61 63.5 66 68.5 71 73.5 76 76

Dixie Drain 2004 SiteID, Year, Day Q 13212890F2004106 95 13212890F2004107 98 13212890F2004108 101 13212890F2004109 104 13212890F2004110 107 13212890F2004111 112.9 13212890F2004112 118.7 13212890F2004113 124.6 13212890F2004114 130.4 13212890F2004115 136.3 13212890F2004116 142.1 13212890F2004117 148 13212890F2004118 148 13212890F2004119 157.8 13212890F2004120 167.7 13212890F2004121 177.5 13212890F2004122 187.3 13212890F2004123 197.2 13212890F2004124 207 13212890F2004125 207 13212890F2004126 212.8 13212890F2004127 218.7 13212890F2004128 224.5 13212890F2004129 230.3 13212890F2004130 236.2 13212890F2004131 242 13212890F2004132 242

Fivemile 2004 SiteID, Year, Day 13210810F2004106 13210810F2004107 13210810F2004108 13210810F2004109 13210810F2004110 13210810F2004111 13210810F2004112 13210810F2004113 13210810F2004114 13210810F2004115 13210810F2004116 13210810F2004117 13210810F2004118 13210810F2004119 13210810F2004120 13210810F2004121 13210810F2004122 13210810F2004123 13210810F2004124 13210810F2004125 13210810F2004126 13210810F2004127 13210810F2004128 13210810F2004129 13210810F2004130 13210810F2004131 13210810F2004132

246

February 2009

Q 76.4 80.6 84.7 88.9 93 98.4 103.9 109.3 114.7 120.1 125.6 131 131 138 145 152 159 166 173 173 178.2 183.3 188.5 193.7 198.8 204 204

Indian Creek 2004 SiteID, Year, Day Q 13211445F2004106 76 13211445F2004107 80 13211445F2004108 84 13211445F2004109 88 13211445F2004110 92 13211445F2004111 94.1 13211445F2004112 96.3 13211445F2004113 98.4 13211445F2004114 100.6 13211445F2004115 102.7 13211445F2004116 104.9 13211445F2004117 107 13211445F2004118 107 13211445F2004119 111.2 13211445F2004120 115.3 13211445F2004121 119.5 13211445F2004122 123.7 13211445F2004123 127.8 13211445F2004124 132 13211445F2004125 132 13211445F2004126 133.5 13211445F2004127 135 13211445F2004128 136.5 13211445F2004129 138 13211445F2004130 139.5 13211445F2004131 141 13211445F2004132 141

Mason Creek 2004 SiteID, Year, Day Q 13210849F2004106 15.1 13210849F2004107 15.9 13210849F2004108 16.6 13210849F2004109 17.3 13210849F2004110 18 13210849F2004111 18.3 13210849F2004112 18.6 13210849F2004113 18.9 13210849F2004114 19.1 13210849F2004115 19.4 13210849F2004116 19.7 13210849F2004117 20 13210849F2004118 20 13210849F2004119 20.5 13210849F2004120 21 13210849F2004121 21.5 13210849F2004122 22 13210849F2004123 22.5 13210849F2004124 23 13210849F2004125 23 13210849F2004126 24 13210849F2004127 25 13210849F2004128 26 13210849F2004129 27 13210849F2004130 28 13210849F2004131 29 13210849F2004132 29

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Conway 2004 SiteID, Year, Day 13212550F2004133 13212550F2004134 13212550F2004135 13212550F2004136 13212550F2004137 13212550F2004138 13212550F2004139 13212550F2004140 13212550F2004141 13212550F2004142 13212550F2004143 13212550F2004144 13212550F2004145 13212550F2004146 13212550F2004147 13212550F2004148 13212550F2004149 13212550F2004150 13212550F2004151 13212550F2004152 13212550F2004153 13212550F2004154 13212550F2004155 13212550F2004156 13212550F2004157 13212550F2004158 13212550F2004159

Q 76.5 77 77.5 78 78.5 79 79 80.2 81.3 82.5 83.7 84.8 86 83.9 81.7 79.6 77.4 75.3 73.1 71 71 71.5 72 72.5 73 73.5 74

Dixie Drain 2004 SiteID, Year, Day Q 13212890F2004133 243.8 13212890F2004134 245.7 13212890F2004135 247.5 13212890F2004136 249.3 13212890F2004137 251.2 13212890F2004138 253 13212890F2004139 253 13212890F2004140 256 13212890F2004141 259 13212890F2004142 262 13212890F2004143 265 13212890F2004144 268 13212890F2004145 271 13212890F2004146 267.9 13212890F2004147 264.7 13212890F2004148 261.6 13212890F2004149 258.4 13212890F2004150 255.3 13212890F2004151 252.1 13212890F2004152 249 13212890F2004153 249 13212890F2004154 246.2 13212890F2004155 243.3 13212890F2004156 240.5 13212890F2004157 237.7 13212890F2004158 234.8 13212890F2004159 232

Fivemile 2004 SiteID, Year, Day 13210810F2004133 13210810F2004134 13210810F2004135 13210810F2004136 13210810F2004137 13210810F2004138 13210810F2004139 13210810F2004140 13210810F2004141 13210810F2004142 13210810F2004143 13210810F2004144 13210810F2004145 13210810F2004146 13210810F2004147 13210810F2004148 13210810F2004149 13210810F2004150 13210810F2004151 13210810F2004152 13210810F2004153 13210810F2004154 13210810F2004155 13210810F2004156 13210810F2004157 13210810F2004158 13210810F2004159

247

February 2009

Q 205.2 206.3 207.5 208.7 209.8 211 211 216.3 221.7 227 232.3 237.7 243 240.6 238.1 235.7 233.3 230.9 228.4 226 226 221.2 216.3 211.5 206.7 201.8 197

Indian Creek 2004 SiteID, Year, Day Q 13211445F2004133 137.8 13211445F2004134 134.7 13211445F2004135 131.5 13211445F2004136 128.3 13211445F2004137 125.2 13211445F2004138 122 13211445F2004139 122 13211445F2004140 124.8 13211445F2004141 127.7 13211445F2004142 130.5 13211445F2004143 133.3 13211445F2004144 136.2 13211445F2004145 139 13211445F2004146 137.1 13211445F2004147 135.3 13211445F2004148 133.4 13211445F2004149 131.6 13211445F2004150 129.7 13211445F2004151 127.9 13211445F2004152 126 13211445F2004153 126 13211445F2004154 119.7 13211445F2004155 113.3 13211445F2004156 107 13211445F2004157 100.7 13211445F2004158 94.3 13211445F2004159 88

Mason Creek 2004 SiteID, Year, Day Q 13210849F2004133 30.2 13210849F2004134 31.3 13210849F2004135 32.5 13210849F2004136 33.7 13210849F2004137 34.8 13210849F2004138 36 13210849F2004139 36 13210849F2004140 35 13210849F2004141 34 13210849F2004142 33 13210849F2004143 32 13210849F2004144 31 13210849F2004145 30 13210849F2004146 29.6 13210849F2004147 29.1 13210849F2004148 28.7 13210849F2004149 28.3 13210849F2004150 27.9 13210849F2004151 27.4 13210849F2004152 27 13210849F2004153 27 13210849F2004154 26.2 13210849F2004155 25.3 13210849F2004156 24.5 13210849F2004157 23.7 13210849F2004158 22.8 13210849F2004159 22

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Conway 2004 SiteID, Year, Day 13212550F2004160 13212550F2004161 13212550F2004162 13212550F2004163 13212550F2004164 13212550F2004165 13212550F2004166 13212550F2004167 13212550F2004168 13212550F2004169 13212550F2004170 13212550F2004171 13212550F2004172 13212550F2004173 13212550F2004174 13212550F2004175 13212550F2004176 13212550F2004177 13212550F2004178 13212550F2004179 13212550F2004180 13212550F2004181 13212550F2004182 13212550F2004183 13212550F2004184 13212550F2004185 13212550F2004186

Q 74 73.1 72.2 71.2 70.3 69.4 68.5 67.5 66.6 65.7 64.8 63.8 62.9 62 62 60.5 59 57.5 56 54.5 53 52 51 50 49 48 47

Dixie Drain 2004 SiteID, Year, Day Q 13212890F2004160 232 13212890F2004161 230.8 13212890F2004162 229.5 13212890F2004163 228.3 13212890F2004164 227.1 13212890F2004165 225.8 13212890F2004166 224.6 13212890F2004167 223.4 13212890F2004168 222.2 13212890F2004169 220.9 13212890F2004170 219.7 13212890F2004171 218.5 13212890F2004172 217.2 13212890F2004173 216 13212890F2004174 216 13212890F2004175 210.5 13212890F2004176 205 13212890F2004177 199.5 13212890F2004178 194 13212890F2004179 188.5 13212890F2004180 183 13212890F2004181 180.3 13212890F2004182 177.6 13212890F2004183 174.9 13212890F2004184 172.1 13212890F2004185 169.4 13212890F2004186 166.7

Fivemile 2004 SiteID, Year, Day 13210810F2004160 13210810F2004161 13210810F2004162 13210810F2004163 13210810F2004164 13210810F2004165 13210810F2004166 13210810F2004167 13210810F2004168 13210810F2004169 13210810F2004170 13210810F2004171 13210810F2004172 13210810F2004173 13210810F2004174 13210810F2004175 13210810F2004176 13210810F2004177 13210810F2004178 13210810F2004179 13210810F2004180 13210810F2004181 13210810F2004182 13210810F2004183 13210810F2004184 13210810F2004185 13210810F2004186

248

February 2009

Q 197 194.4 191.8 189.2 186.5 183.9 181.3 178.7 176.1 173.5 170.8 168.2 165.6 163 163 160.3 157.7 155 152.3 149.7 147 145.9 144.7 143.6 142.4 141.3 140.1

Indian Creek 2004 SiteID, Year, Day Q 13211445F2004160 88 13211445F2004161 87.1 13211445F2004162 86.2 13211445F2004163 85.2 13211445F2004164 84.3 13211445F2004165 83.4 13211445F2004166 82.5 13211445F2004167 81.5 13211445F2004168 80.6 13211445F2004169 79.7 13211445F2004170 78.8 13211445F2004171 77.8 13211445F2004172 76.9 13211445F2004173 76 13211445F2004174 76 13211445F2004175 73.7 13211445F2004176 71.3 13211445F2004177 69 13211445F2004178 66.7 13211445F2004179 64.3 13211445F2004180 62 13211445F2004181 60.7 13211445F2004182 59.4 13211445F2004183 58.1 13211445F2004184 56.9 13211445F2004185 55.6 13211445F2004186 54.3

Mason Creek 2004 SiteID, Year, Day Q 13210849F2004160 22 13210849F2004161 21.7 13210849F2004162 21.4 13210849F2004163 21.1 13210849F2004164 20.8 13210849F2004165 20.5 13210849F2004166 20.2 13210849F2004167 19.8 13210849F2004168 19.5 13210849F2004169 19.2 13210849F2004170 18.9 13210849F2004171 18.6 13210849F2004172 18.3 13210849F2004173 18 13210849F2004174 18 13210849F2004175 18.3 13210849F2004176 18.7 13210849F2004177 19 13210849F2004178 19.3 13210849F2004179 19.7 13210849F2004180 20 13210849F2004181 19.9 13210849F2004182 19.7 13210849F2004183 19.6 13210849F2004184 19.4 13210849F2004185 19.3 13210849F2004186 19.1

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Conway 2004 SiteID, Year, Day 13212550F2004187 13212550F2004188 13212550F2004189 13212550F2004190 13212550F2004191 13212550F2004192 13212550F2004193 13212550F2004194 13212550F2004195 13212550F2004196 13212550F2004197 13212550F2004198 13212550F2004199 13212550F2004200 13212550F2004201 13212550F2004202 13212550F2004203 13212550F2004204 13212550F2004205 13212550F2004206 13212550F2004207 13212550F2004208 13212550F2004209 13212550F2004210 13212550F2004211 13212550F2004212 13212550F2004213

Q 46 46 45.5 45 44.5 44 43.5 43 43 41.8 40.7 39.5 38.3 37.2 36 36 36.5 37 37.5 38 38.5 39 39 37.7 36.4 35.1 33.8

Dixie Drain 2004 SiteID, Year, Day Q 13212890F2004187 164 13212890F2004188 164 13212890F2004189 163.2 13212890F2004190 162.3 13212890F2004191 161.5 13212890F2004192 160.7 13212890F2004193 159.8 13212890F2004194 159 13212890F2004195 159 13212890F2004196 161.8 13212890F2004197 164.7 13212890F2004198 167.5 13212890F2004199 170.3 13212890F2004200 173.2 13212890F2004201 176 13212890F2004202 176 13212890F2004203 173.7 13212890F2004204 171.4 13212890F2004205 169.1 13212890F2004206 166.8 13212890F2004207 164.5 13212890F2004208 162.2 13212890F2004209 162 13212890F2004210 160.5 13212890F2004211 159 13212890F2004212 157.5 13212890F2004213 156

Fivemile 2004 SiteID, Year, Day 13210810F2004187 13210810F2004188 13210810F2004189 13210810F2004190 13210810F2004191 13210810F2004192 13210810F2004193 13210810F2004194 13210810F2004195 13210810F2004196 13210810F2004197 13210810F2004198 13210810F2004199 13210810F2004200 13210810F2004201 13210810F2004202 13210810F2004203 13210810F2004204 13210810F2004205 13210810F2004206 13210810F2004207 13210810F2004208 13210810F2004209 13210810F2004210 13210810F2004211 13210810F2004212 13210810F2004213

249

February 2009

Q 139 139 135.2 131.3 127.5 123.7 119.8 116 116 116.8 117.7 118.5 119.3 120.2 121 121 120.2 119.4 118.6 117.8 117 116.2 116 114.8 113.6 112.4 111.2

Indian Creek 2004 SiteID, Year, Day Q 13211445F2004187 53 13211445F2004188 53 13211445F2004189 56.8 13211445F2004190 60.7 13211445F2004191 64.5 13211445F2004192 68.3 13211445F2004193 72.2 13211445F2004194 76 13211445F2004195 76 13211445F2004196 76.8 13211445F2004197 77.7 13211445F2004198 78.5 13211445F2004199 79.3 13211445F2004200 80.2 13211445F2004201 81 13211445F2004202 81 13211445F2004203 82.8 13211445F2004204 84.6 13211445F2004205 86.4 13211445F2004206 88.2 13211445F2004207 90 13211445F2004208 91.8 13211445F2004209 92 13211445F2004210 90.5 13211445F2004211 89 13211445F2004212 87.5 13211445F2004213 86

Mason Creek 2004 SiteID, Year, Day Q 13210849F2004187 19 13210849F2004188 19 13210849F2004189 18.7 13210849F2004190 18.3 13210849F2004191 18 13210849F2004192 17.7 13210849F2004193 17.3 13210849F2004194 17 13210849F2004195 17 13210849F2004196 17.7 13210849F2004197 18.3 13210849F2004198 19 13210849F2004199 19.7 13210849F2004200 20.3 13210849F2004201 21 13210849F2004202 21 13210849F2004203 20.7 13210849F2004204 20.4 13210849F2004205 20.1 13210849F2004206 19.8 13210849F2004207 19.5 13210849F2004208 19.2 13210849F2004209 19 13210849F2004210 18.8 13210849F2004211 18.6 13210849F2004212 18.4 13210849F2004213 18.2

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Conway 2004 SiteID, Year, Day 13212550F2004214 13212550F2004215 13212550F2004216 13212550F2004217 13212550F2004218 13212550F2004219 13212550F2004220 13212550F2004221 13212550F2004222 13212550F2004223 13212550F2004224 13212550F2004225 13212550F2004226 13212550F2004227 13212550F2004228 13212550F2004229 13212550F2004230 13212550F2004231 13212550F2004232 13212550F2004233 13212550F2004234 13212550F2004235 13212550F2004236 13212550F2004237 13212550F2004238 13212550F2004239 13212550F2004240

Q 32.5 31.2 31 30.3 29.6 28.9 28.2 27.5 26.8 27 28.2 29.4 30.6 31.8 33 34.2 34 35.5 37 38.5 40 41.5 43 43 43.7 44.4 45.1

Dixie Drain 2004 SiteID, Year, Day Q 13212890F2004214 154.5 13212890F2004215 153 13212890F2004216 153 13212890F2004217 152 13212890F2004218 151 13212890F2004219 150 13212890F2004220 149 13212890F2004221 148 13212890F2004222 147 13212890F2004223 147 13212890F2004224 149.3 13212890F2004225 151.6 13212890F2004226 153.9 13212890F2004227 156.2 13212890F2004228 158.5 13212890F2004229 160.8 13212890F2004230 161 13212890F2004231 163 13212890F2004232 165 13212890F2004233 167 13212890F2004234 169 13212890F2004235 171 13212890F2004236 173 13212890F2004237 173 13212890F2004238 170.7 13212890F2004239 168.4 13212890F2004240 166.1

Fivemile 2004 SiteID, Year, Day 13210810F2004214 13210810F2004215 13210810F2004216 13210810F2004217 13210810F2004218 13210810F2004219 13210810F2004220 13210810F2004221 13210810F2004222 13210810F2004223 13210810F2004224 13210810F2004225 13210810F2004226 13210810F2004227 13210810F2004228 13210810F2004229 13210810F2004230 13210810F2004231 13210810F2004232 13210810F2004233 13210810F2004234 13210810F2004235 13210810F2004236 13210810F2004237 13210810F2004238 13210810F2004239 13210810F2004240

250

February 2009

Q 110 108.8 109 106.2 103.4 100.6 97.8 95 92.2 92 93.8 95.6 97.4 99.2 101 102.8 103 107 111 115 119 123 127 127 125.2 123.4 121.6

Indian Creek 2004 SiteID, Year, Day Q 13211445F2004214 84.5 13211445F2004215 83 13211445F2004216 83 13211445F2004217 80.7 13211445F2004218 78.4 13211445F2004219 76.1 13211445F2004220 73.8 13211445F2004221 71.5 13211445F2004222 69.2 13211445F2004223 69 13211445F2004224 69.5 13211445F2004225 70 13211445F2004226 70.5 13211445F2004227 71 13211445F2004228 71.5 13211445F2004229 72 13211445F2004230 72 13211445F2004231 70.5 13211445F2004232 69 13211445F2004233 67.5 13211445F2004234 66 13211445F2004235 64.5 13211445F2004236 63 13211445F2004237 63 13211445F2004238 61.8 13211445F2004239 60.6 13211445F2004240 59.4

Mason Creek 2004 SiteID, Year, Day Q 13210849F2004214 18 13210849F2004215 17.8 13210849F2004216 18 13210849F2004217 18 13210849F2004218 18 13210849F2004219 18 13210849F2004220 18 13210849F2004221 18 13210849F2004222 18 13210849F2004223 18 13210849F2004224 18.8 13210849F2004225 19.6 13210849F2004226 20.4 13210849F2004227 21.2 13210849F2004228 22 13210849F2004229 22.8 13210849F2004230 23 13210849F2004231 22.5 13210849F2004232 22 13210849F2004233 21.5 13210849F2004234 21 13210849F2004235 20.5 13210849F2004236 20 13210849F2004237 20 13210849F2004238 19.7 13210849F2004239 19.4 13210849F2004240 19.1

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Conway 2004 SiteID, Year, Day 13212550F2004241 13212550F2004242 13212550F2004243 13212550F2004244 13212550F2004245 13212550F2004246 13212550F2004247 13212550F2004248 13212550F2004249 13212550F2004250 13212550F2004251 13212550F2004252 13212550F2004253 13212550F2004254 13212550F2004255 13212550F2004256 13212550F2004257 13212550F2004258 13212550F2004259 13212550F2004260 13212550F2004261 13212550F2004262 13212550F2004263 13212550F2004264 13212550F2004265 13212550F2004266 13212550F2004267

Q 45.8 46.5 47.2 47 45.7 44.4 43.1 41.8 40.5 39.2 39 37.8 36.6 35.4 34.2 33 31.8 32 34.3 36.6 38.9 41.2 43.5 45.8 46 46.5 47

Dixie Drain 2004 SiteID, Year, Day Q 13212890F2004241 163.8 13212890F2004242 161.5 13212890F2004243 159.2 13212890F2004244 159 13212890F2004245 157 13212890F2004246 155 13212890F2004247 153 13212890F2004248 151 13212890F2004249 149 13212890F2004250 147 13212890F2004251 147 13212890F2004252 151.3 13212890F2004253 155.6 13212890F2004254 159.9 13212890F2004255 164.2 13212890F2004256 168.5 13212890F2004257 172.8 13212890F2004258 173 13212890F2004259 179.3 13212890F2004260 185.6 13212890F2004261 191.9 13212890F2004262 198.2 13212890F2004263 204.5 13212890F2004264 210.8 13212890F2004265 210 13212890F2004266 209.2 13212890F2004267 208.4

Fivemile 2004 SiteID, Year, Day 13210810F2004241 13210810F2004242 13210810F2004243 13210810F2004244 13210810F2004245 13210810F2004246 13210810F2004247 13210810F2004248 13210810F2004249 13210810F2004250 13210810F2004251 13210810F2004252 13210810F2004253 13210810F2004254 13210810F2004255 13210810F2004256 13210810F2004257 13210810F2004258 13210810F2004259 13210810F2004260 13210810F2004261 13210810F2004262 13210810F2004263 13210810F2004264 13210810F2004265 13210810F2004266 13210810F2004267

251

February 2009

Q 119.8 118 116.2 116 115.2 114.4 113.6 112.8 112 111.2 111 113.5 116 118.5 121 123.5 126 126 129.5 133 136.5 140 143.5 147 147 148 149

Indian Creek 2004 SiteID, Year, Day Q 13211445F2004241 58.2 13211445F2004242 57 13211445F2004243 55.8 13211445F2004244 56 13211445F2004245 54.5 13211445F2004246 53 13211445F2004247 51.5 13211445F2004248 50 13211445F2004249 48.5 13211445F2004250 47 13211445F2004251 47 13211445F2004252 49.5 13211445F2004253 52 13211445F2004254 54.5 13211445F2004255 57 13211445F2004256 59.5 13211445F2004257 62 13211445F2004258 62 13211445F2004259 61.5 13211445F2004260 61 13211445F2004261 60.5 13211445F2004262 60 13211445F2004263 59.5 13211445F2004264 59 13211445F2004265 59 13211445F2004266 60 13211445F2004267 61

Mason Creek 2004 SiteID, Year, Day Q 13210849F2004241 18.8 13210849F2004242 18.5 13210849F2004243 18.2 13210849F2004244 18 13210849F2004245 18.3 13210849F2004246 18.6 13210849F2004247 18.9 13210849F2004248 19.2 13210849F2004249 19.5 13210849F2004250 19.8 13210849F2004251 20 13210849F2004252 19.5 13210849F2004253 19 13210849F2004254 18.5 13210849F2004255 18 13210849F2004256 17.5 13210849F2004257 17 13210849F2004258 17 13210849F2004259 17.3 13210849F2004260 17.6 13210849F2004261 17.9 13210849F2004262 18.2 13210849F2004263 18.5 13210849F2004264 18.8 13210849F2004265 19 13210849F2004266 19 13210849F2004267 19

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Conway 2004 SiteID, Year, Day 13212550F2004268 13212550F2004269 13212550F2004270 13212550F2004271 13212550F2004272 13212550F2004273 13212550F2004274 13212550F2004275 13212550F2004276 13212550F2004277 13212550F2004278 13212550F2004279 13212550F2004280 13212550F2004281 13212550F2004282 13212550F2004283 13212550F2004284 13212550F2004285 13212550F2004286 13212550F2004287 13212550F2004288 13212550F2004289 13212550F2004290 13212550F2004291 13212550F2004292 13212550F2004293 13212550F2004294

Q 47.5 48 48.5 49 49 48.7 48.4 48.1 47.8 47.5 47.2 48 48.8 49.6 50.4 51.2 52 52.8 51.3 49.8 48.3 46.8 45.3 43.8 42.3 40.7 39.1

Dixie Drain 2004 SiteID, Year, Day Q 13212890F2004268 207.6 13212890F2004269 206.8 13212890F2004270 206 13212890F2004271 205.2 13212890F2004272 205 13212890F2004273 202.5 13212890F2004274 200 13212890F2004275 197.5 13212890F2004276 195 13212890F2004277 192.5 13212890F2004278 190 13212890F2004279 189.1 13212890F2004280 188.2 13212890F2004281 187.3 13212890F2004282 186.4 13212890F2004283 185.5 13212890F2004284 184.6 13212890F2004285 183.7 13212890F2004286 181 13212890F2004287 178.3 13212890F2004288 175.6 13212890F2004289 172.9 13212890F2004290 170.2 13212890F2004291 167.5 13212890F2004292 164.8 13212890F2004293 161.7 13212890F2004294 158.6

Fivemile 2004 SiteID, Year, Day 13210810F2004268 13210810F2004269 13210810F2004270 13210810F2004271 13210810F2004272 13210810F2004273 13210810F2004274 13210810F2004275 13210810F2004276 13210810F2004277 13210810F2004278 13210810F2004279 13210810F2004280 13210810F2004281 13210810F2004282 13210810F2004283 13210810F2004284 13210810F2004285 13210810F2004286 13210810F2004287 13210810F2004288 13210810F2004289 13210810F2004290 13210810F2004291 13210810F2004292 13210810F2004293 13210810F2004294

252

February 2009

Q 150 151 152 153 153 150.7 148.4 146.1 143.8 141.5 139.2 137.5 135.8 134.1 132.4 130.7 129 127.3 125.5 123.7 121.9 120.1 118.3 116.5 114.7 111.1 107.5

Indian Creek 2004 SiteID, Year, Day Q 13211445F2004268 62 13211445F2004269 63 13211445F2004270 64 13211445F2004271 65 13211445F2004272 65 13211445F2004273 63.5 13211445F2004274 62 13211445F2004275 60.5 13211445F2004276 59 13211445F2004277 57.5 13211445F2004278 56 13211445F2004279 58 13211445F2004280 60 13211445F2004281 62 13211445F2004282 64 13211445F2004283 66 13211445F2004284 68 13211445F2004285 70 13211445F2004286 68.9 13211445F2004287 67.8 13211445F2004288 66.7 13211445F2004289 65.6 13211445F2004290 64.5 13211445F2004291 63.4 13211445F2004292 62.3 13211445F2004293 63.6 13211445F2004294 64.9

Mason Creek 2004 SiteID, Year, Day Q 13210849F2004268 19 13210849F2004269 19 13210849F2004270 19 13210849F2004271 19 13210849F2004272 19 13210849F2004273 18.8 13210849F2004274 18.6 13210849F2004275 18.4 13210849F2004276 18.2 13210849F2004277 18 13210849F2004278 17.8 13210849F2004279 18.5 13210849F2004280 19.2 13210849F2004281 19.9 13210849F2004282 20.6 13210849F2004283 21.3 13210849F2004284 22 13210849F2004285 22.7 13210849F2004286 22.9 13210849F2004287 23.1 13210849F2004288 23.3 13210849F2004289 23.5 13210849F2004290 23.7 13210849F2004291 23.9 13210849F2004292 24.1 13210849F2004293 22.8 13210849F2004294 21.4

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Conway 2004 SiteID, Year, Day 13212550F2004295 13212550F2004296 13212550F2004297 13212550F2004298 13212550F2004299 13212550F2004300 13212550F2004301 13212550F2004302 13212550F2004303 13212550F2004304 13212550F2004305

Q 37.5 35.9 34.3 32.7 31.1 31.1 31.1 31.1 31.1 31.1 31.1

Mason Drain 2004 SiteID, Year, Day Q 13210980F2003274 125.2 13210980F2003275 123.3 13210980F2003276 121.5 13210980F2003277 119.7 13210980F2003278 117.8 13210980F2003279 116 13210980F2003280 113.7 13210980F2003281 111.4 13210980F2003282 109.1 13210980F2003283 106.9 13210980F2003284 104.6 13210980F2003285 102.3 13210980F2003286 100

Dixie Drain 2004 SiteID, Year, Day Q 13212890F2004295 155.5 13212890F2004296 152.4 13212890F2004297 149.3 13212890F2004298 146.2 13212890F2004299 143.1 13212890F2004300 143.1 13212890F2004301 143.1 13212890F2004302 143.1 13212890F2004303 143.1 13212890F2004304 143.1 13212890F2004305 143.1

Fivemile 2004 SiteID, Year, Day 13210810F2004295 13210810F2004296 13210810F2004297 13210810F2004298 13210810F2004299 13210810F2004300 13210810F2004301 13210810F2004302 13210810F2004303 13210810F2004304 13210810F2004305

February 2009

Q 103.9 100.3 96.7 93.1 93.1 93.1 93.1 93.1 93.1 93.1 93.1

N. Middleton 2004 S. Middleton 2004 SiteID, Year, Day Q SiteID, Year, Day Q 13210824F2003274 42.5 13210831F2003274 83.7 82.3 13210824F2003275 42 13210831F2003275 13210831F2003276 81 13210824F2003276 41.5 79.7 13210824F2003277 41 13210831F2003277 78.3 13210824F2003278 40.5 13210831F2003278 77 13210824F2003279 40 13210831F2003279 76 13210824F2003280 39.6 13210831F2003280 75 13210824F2003281 39.1 13210831F2003281 74 13210824F2003282 38.7 13210831F2003282 73 13210824F2003283 38.3 13210831F2003283 72 13210824F2003284 37.9 13210831F2003284 71 13210824F2003285 37.4 13210831F2003285 70 13210824F2003286 37 13210831F2003286

253

Indian Creek 2004 SiteID, Year, Day Q 13211445F2004295 66.2 13211445F2004296 67.5 13211445F2004297 68.8 13211445F2004298 70.1 13211445F2004299 70.1 13211445F2004300 70.1 13211445F2004301 70.1 13211445F2004302 70.1 13211445F2004303 70.1 13211445F2004304 70.1 13211445F2004305 70.1

Mason Creek 2004 SiteID, Year, Day Q 13210849F2004295 20 13210849F2004296 18.7 13210849F2004297 17.4 13210849F2004298 16 13210849F2004299 16 13210849F2004300 16 13210849F2004301 16 13210849F2004302 16 13210849F2004303 16 13210849F2004304 16 13210849F2004305 16

Thurman 2004 SiteID, Year, Day 13209450W2003274 13209450W2003275 13209450W2003276 13209450W2003277 13209450W2003278 13209450W2003279 13209450W2003280 13209450W2003281 13209450W2003282 13209450W2003283 13209450W2003284 13209450W2003285 13209450W2003286

Willow Creek 2004 SiteID, Year, Day Q 13210835F2003274 11.2 13210835F2003275 11.3 13210835F2003276 11.5 13210835F2003277 11.7 13210835F2003278 11.8 13210835F2003279 12 13210835F2003280 11.7 13210835F2003281 11.4 13210835F2003282 11.1 13210835F2003283 10.9 13210835F2003284 10.6 13210835F2003285 10.3 13210835F2003286 10

Q 17 17 17 17 17 17 17.1 17.3 17.4 17.5 17.6 17.8 17.9

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Mason Drain 2004 SiteID, Year, Day Q 13210980F2003287 97.6 13210980F2003288 95.1 13210980F2003289 92.7 13210980F2003290 90.3 13210980F2003291 87.9 13210980F2003292 85.4 13210980F2003293 83 13210980F2003294 78.4 13210980F2003295 73.9 13210980F2003296 69.3 13210980F2003297 64.7 13210980F2003298 60.1 13210980F2003299 55.6 13210980F2003300 51 13210980F2003301 51 13210980F2003302 51 13210980F2003303 51 13210980F2003304 51 13210980F2004092 29 13210980F2004093 29 13210980F2004094 29 13210980F2004095 29 13210980F2004096 29 13210980F2004097 30.3 13210980F2004098 31.6 13210980F2004099 32.9 13210980F2004100 34.1 13210980F2004101 35.4

N. Middleton 2004 SiteID, Year, Day Q 13210824F2003287

36

13210824F2003288

35

13210824F2003289

34

13210824F2003290

33

13210824F2003291

32

13210824F2003292

31

13210824F2003293

30

13210824F2003294

29

13210824F2003295

28

13210824F2003296

27

13210824F2003297

26

13210824F2003298

25

13210824F2003299

24

13210824F2003300

23

13210824F2003301

23

13210824F2003302

23

13210824F2003303

23

13210824F2003304

23

13210824F2004092

18

13210824F2004093

18

13210824F2004094

18

13210824F2004095

18

13210824F2004096

18

13210824F2004097

18.9

13210824F2004098

19.7

13210824F2004099

20.6

13210824F2004100

21.4

13210824F2004101

22.3

S. Middleton 2004 SiteID, Year, Day Q 13210831F2003287 68.7 13210831F2003288 67.4 13210831F2003289 66.1 13210831F2003290 64.9 13210831F2003291 63.6 13210831F2003292 62.3 13210831F2003293 61 13210831F2003294 59 13210831F2003295 57 13210831F2003296 55 13210831F2003297 53 13210831F2003298 51 13210831F2003299 49 13210831F2003300 47 13210831F2003301 47 13210831F2003302 47 13210831F2003303 47 13210831F2003304 47 13210831F2004092 32 13210831F2004093 32 13210831F2004094 32 13210831F2004095 32 13210831F2004096 32 13210831F2004097 34.4 13210831F2004098 36.9 13210831F2004099 39.3 13210831F2004100 41.7 13210831F2004101 44.1

254

February 2009

Thurman 2004 SiteID, Year, Day 13209450W2003287 13209450W2003288 13209450W2003289 13209450W2003290 13209450W2003291 13209450W2003292 13209450W2003293 13209450W2003294 13209450W2003295 13209450W2003296 13209450W2003297 13209450W2003298 13209450W2003299 13209450W2003300 13209450W2003301 13209450W2003302 13209450W2003303 13209450W2003304 13209450W2004092 13209450W2004093 13209450W2004094 13209450W2004095 13209450W2004096 13209450W2004097 13209450W2004098 13209450W2004099 13209450W2004100 13209450W2004101

Q 18 17.8 17.7 17.5 17.3 17.2 17 16.7 16.4 16.1 15.9 15.6 15.3 15 15 15 15 15 6 6 6 6 6 6.4 6.9 7.3 7.7 8.1

Willow Creek 2004 SiteID, Year, Day Q 13210835F2003287 9.6 13210835F2003288 9.1 13210835F2003289 8.7 13210835F2003290 8.3 13210835F2003291 7.9 13210835F2003292 7.4 13210835F2003293 7 13210835F2003294 6.3 13210835F2003295 5.6 13210835F2003296 4.9 13210835F2003297 4.1 13210835F2003298 3.4 13210835F2003299 2.7 13210835F2003300 2 13210835F2003301 2 13210835F2003302 2 13210835F2003303 2 13210835F2003304 2 13210835F2004092 1 13210835F2004093 1 13210835F2004094 1 13210835F2004095 1 13210835F2004096 1 13210835F2004097 1.3 13210835F2004098 1.6 13210835F2004099 1.9 13210835F2004100 2.1 13210835F2004101 2.4

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Mason Drain 2004 SiteID, Year, Day Q 13210980F2004102 36.7 13210980F2004103 38 13210980F2004104 41.6 13210980F2004105 45.1 13210980F2004106 48.7 13210980F2004107 52.3 13210980F2004108 55.9 13210980F2004109 59.4 13210980F2004110 63 13210980F2004111 66 13210980F2004112 69 13210980F2004113 72 13210980F2004114 75 13210980F2004115 78 13210980F2004116 81 13210980F2004117 84 13210980F2004118 84 13210980F2004119 88 13210980F2004120 92 13210980F2004121 96 13210980F2004122 100 13210980F2004123 104 13210980F2004124 108 13210980F2004125 108 13210980F2004126 113.5 13210980F2004127 119 13210980F2004128 124.5 13210980F2004129 130

N. Middleton 2004 SiteID, Year, Day Q 13210824F2004102

23.1

13210824F2004103

24

13210824F2004104

26.4

13210824F2004105

28.9

13210824F2004106

31.3

13210824F2004107

33.7

13210824F2004108

36.1

13210824F2004109

38.6

13210824F2004110

41

13210824F2004111

41.3

13210824F2004112

41.6

13210824F2004113

41.9

13210824F2004114

42.1

13210824F2004115

42.4

13210824F2004116

42.7

13210824F2004117

43

13210824F2004118

43

13210824F2004119

43.3

13210824F2004120

43.7

13210824F2004121

44

13210824F2004122

44.3

13210824F2004123

44.7

13210824F2004124

45

13210824F2004125

45

13210824F2004126

46

13210824F2004127

47

13210824F2004128

48

13210824F2004129

49

S. Middleton 2004 SiteID, Year, Day Q 13210831F2004102 46.6 13210831F2004103 49 13210831F2004104 51 13210831F2004105 53 13210831F2004106 55 13210831F2004107 57 13210831F2004108 59 13210831F2004109 61 13210831F2004110 63 13210831F2004111 67.1 13210831F2004112 71.3 13210831F2004113 75.4 13210831F2004114 79.6 13210831F2004115 83.7 13210831F2004116 87.9 13210831F2004117 92 13210831F2004118 92 13210831F2004119 93.8 13210831F2004120 95.7 13210831F2004121 97.5 13210831F2004122 99.3 13210831F2004123 101.2 13210831F2004124 103 13210831F2004125 103 13210831F2004126 107.2 13210831F2004127 111.3 13210831F2004128 115.5 13210831F2004129 119.7

255

February 2009

Thurman 2004 SiteID, Year, Day 13209450W2004102 13209450W2004103 13209450W2004104 13209450W2004105 13209450W2004106 13209450W2004107 13209450W2004108 13209450W2004109 13209450W2004110 13209450W2004111 13209450W2004112 13209450W2004113 13209450W2004114 13209450W2004115 13209450W2004116 13209450W2004117 13209450W2004118 13209450W2004119 13209450W2004120 13209450W2004121 13209450W2004122 13209450W2004123 13209450W2004124 13209450W2004125 13209450W2004126 13209450W2004127 13209450W2004128 13209450W2004129

Q 8.6 9 10.3 11.6 12.9 14.1 15.4 16.7 18 18.4 18.9 19.3 19.7 20.1 20.6 21 21 21.3 21.7 22 22.3 22.7 23 23 23.5 24 24.5 25

Willow Creek 2004 SiteID, Year, Day Q 13210835F2004102 2.7 13210835F2004103 3 13210835F2004104 3.7 13210835F2004105 4.4 13210835F2004106 5.1 13210835F2004107 5.9 13210835F2004108 6.6 13210835F2004109 7.3 13210835F2004110 8 13210835F2004111 9.4 13210835F2004112 10.9 13210835F2004113 12.3 13210835F2004114 13.7 13210835F2004115 15.1 13210835F2004116 16.6 13210835F2004117 18 13210835F2004118 16 13210835F2004119 17.8 13210835F2004120 19.7 13210835F2004121 21.5 13210835F2004122 23.3 13210835F2004123 25.2 13210835F2004124 27 13210835F2004125 27 13210835F2004126 28.5 13210835F2004127 30 13210835F2004128 31.5 13210835F2004129 33

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Mason Drain 2004 SiteID, Year, Day Q 13210980F2004130 135.5 13210980F2004131 141 13210980F2004132 141 13210980F2004133 148.7 13210980F2004134 156.3 13210980F2004135 164 13210980F2004136 171.7 13210980F2004137 179.3 13210980F2004138 187 13210980F2004139 187 13210980F2004140 183.3 13210980F2004141 179.7 13210980F2004142 176 13210980F2004143 172.3 13210980F2004144 168.7 13210980F2004145 165 13210980F2004146 164.6 13210980F2004147 164.1 13210980F2004148 163.7 13210980F2004149 163.3 13210980F2004150 162.9 13210980F2004151 162.4 13210980F2004152 162 13210980F2004153 162 13210980F2004154 160.2 13210980F2004155 158.3 13210980F2004156 156.5 13210980F2004157 154.7

N. Middleton 2004 SiteID, Year, Day Q 13210824F2004130

50

13210824F2004131

51

13210824F2004132

51

13210824F2004133

51.3

13210824F2004134

51.7

13210824F2004135

52

13210824F2004136

52.3

13210824F2004137

52.7

13210824F2004138

53

13210824F2004139

53

13210824F2004140

53.7

13210824F2004141

54.3

13210824F2004142

55

13210824F2004143

55.7

13210824F2004144

56.3

13210824F2004145

57

13210824F2004146

55.9

13210824F2004147

54.7

13210824F2004148

53.6

13210824F2004149

52.4

13210824F2004150

51.3

13210824F2004151

50.1

13210824F2004152

49

13210824F2004153

49

13210824F2004154

47.7

13210824F2004155

46.3

13210824F2004156

45

13210824F2004157

43.7

S. Middleton 2004 SiteID, Year, Day Q 13210831F2004130 123.8 13210831F2004131 128 13210831F2004132 128 13210831F2004133 129 13210831F2004134 130 13210831F2004135 131 13210831F2004136 132 13210831F2004137 133 13210831F2004138 134 13210831F2004139 134 13210831F2004140 134.7 13210831F2004141 135.3 13210831F2004142 136 13210831F2004143 136.7 13210831F2004144 137.3 13210831F2004145 138 13210831F2004146 136 13210831F2004147 134 13210831F2004148 132 13210831F2004149 130 13210831F2004150 128 13210831F2004151 126 13210831F2004152 124 13210831F2004153 124 13210831F2004154 121 13210831F2004155 118 13210831F2004156 115 13210831F2004157 112

256

February 2009

Thurman 2004 SiteID, Year, Day 13209450W2004130 13209450W2004131 13209450W2004132 13209450W2004133 13209450W2004134 13209450W2004135 13209450W2004136 13209450W2004137 13209450W2004138 13209450W2004139 13209450W2004140 13209450W2004141 13209450W2004142 13209450W2004143 13209450W2004144 13209450W2004145 13209450W2004146 13209450W2004147 13209450W2004148 13209450W2004149 13209450W2004150 13209450W2004151 13209450W2004152 13209450W2004153 13209450W2004154 13209450W2004155 13209450W2004156 13209450W2004157

Q 25.5 26 26 25.7 25.3 25 24.7 24.3 24 24 25 26 27 28 29 30 29.4 28.9 28.3 27.7 27.1 26.6 26 26 25 24 23 22

Willow Creek 2004 SiteID, Year, Day Q 13210835F2004130 34.5 13210835F2004131 36 13210835F2004132 36 13210835F2004133 38.2 13210835F2004134 40.3 13210835F2004135 42.5 13210835F2004136 44.7 13210835F2004137 46.8 13210835F2004138 49 13210835F2004139 49 13210835F2004140 49.5 13210835F2004141 50 13210835F2004142 50.5 13210835F2004143 51 13210835F2004144 51.5 13210835F2004145 52 13210835F2004146 49.4 13210835F2004147 46.9 13210835F2004148 44.3 13210835F2004149 41.7 13210835F2004150 39.1 13210835F2004151 36.6 13210835F2004152 34 13210835F2004153 34 13210835F2004154 31.3 13210835F2004155 28.7 13210835F2004156 26 13210835F2004157 23.3

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Mason Drain 2004 SiteID, Year, Day Q 13210980F2004158 152.8 13210980F2004159 151 13210980F2004160 151 13210980F2004161 150.1 13210980F2004162 149.2 13210980F2004163 148.2 13210980F2004164 147.3 13210980F2004165 146.4 13210980F2004166 145.5 13210980F2004167 144.5 13210980F2004168 143.6 13210980F2004169 142.7 13210980F2004170 141.8 13210980F2004171 140.8 13210980F2004172 139.9 13210980F2004173 139 13210980F2004174 139 13210980F2004175 140.3 13210980F2004176 141.7 13210980F2004177 143 13210980F2004178 144.3 13210980F2004179 145.7 13210980F2004180 147 13210980F2004181 145.1 13210980F2004182 143.3 13210980F2004183 141.4 13210980F2004184 139.6 13210980F2004185 137.7

N. Middleton 2004 SiteID, Year, Day Q 13210824F2004158

42.3

13210824F2004159

41

13210824F2004160

41

13210824F2004161

40.8

13210824F2004162

40.5

13210824F2004163

40.3

13210824F2004164

40.1

13210824F2004165

39.8

13210824F2004166

39.6

13210824F2004167

39.4

13210824F2004168

39.2

13210824F2004169

38.9

13210824F2004170

38.7

13210824F2004171

38.5

13210824F2004172

38.2

13210824F2004173

38

13210824F2004174

38

13210824F2004175

37.7

13210824F2004176

37.3

13210824F2004177

37

13210824F2004178

36.7

13210824F2004179

36.3

13210824F2004180

36

13210824F2004181

35.6

13210824F2004182

35.1

13210824F2004183

34.7

13210824F2004184

34.3

13210824F2004185

33.9

S. Middleton 2004 SiteID, Year, Day Q 13210831F2004158 109 13210831F2004159 106 13210831F2004160 106 13210831F2004161 105 13210831F2004162 104 13210831F2004163 103 13210831F2004164 102 13210831F2004165 101 13210831F2004166 100 13210831F2004167 99 13210831F2004168 98 13210831F2004169 97 13210831F2004170 96 13210831F2004171 95 13210831F2004172 94 13210831F2004173 93 13210831F2004174 93 13210831F2004175 92 13210831F2004176 91 13210831F2004177 90 13210831F2004178 89 13210831F2004179 88 13210831F2004180 87 13210831F2004181 86.6 13210831F2004182 86.1 13210831F2004183 85.7 13210831F2004184 85.3 13210831F2004185 84.9

257

February 2009

Thurman 2004 SiteID, Year, Day 13209450W2004158 13209450W2004159 13209450W2004160 13209450W2004161 13209450W2004162 13209450W2004163 13209450W2004164 13209450W2004165 13209450W2004166 13209450W2004167 13209450W2004168 13209450W2004169 13209450W2004170 13209450W2004171 13209450W2004172 13209450W2004173 13209450W2004174 13209450W2004175 13209450W2004176 13209450W2004177 13209450W2004178 13209450W2004179 13209450W2004180 13209450W2004181 13209450W2004182 13209450W2004183 13209450W2004184 13209450W2004185

Q 21 20 20 19.9 19.8 19.8 19.7 19.6 19.5 19.5 19.4 19.3 19.2 19.2 19.1 19 19 18.8 18.7 18.5 18.3 18.2 18 18 18 18 18 18

Willow Creek 2004 SiteID, Year, Day Q 13210835F2004158 20.7 13210835F2004159 18 13210835F2004160 18 13210835F2004161 17.5 13210835F2004162 17.1 13210835F2004163 16.6 13210835F2004164 16.2 13210835F2004165 15.7 13210835F2004166 15.2 13210835F2004167 14.8 13210835F2004168 14.3 13210835F2004169 13.8 13210835F2004170 13.4 13210835F2004171 12.9 13210835F2004172 12.5 13210835F2004173 12 13210835F2004174 12 13210835F2004175 11.2 13210835F2004176 10.3 13210835F2004177 9.5 13210835F2004178 8.7 13210835F2004179 7.8 13210835F2004180 7 13210835F2004181 6.9 13210835F2004182 6.7 13210835F2004183 6.6 13210835F2004184 6.4 13210835F2004185 6.3

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Mason Drain 2004 SiteID, Year, Day Q 13210980F2004186 135.9 13210980F2004187 134 13210980F2004188 134 13210980F2004189 131.8 13210980F2004190 129.7 13210980F2004191 127.5 13210980F2004192 125.3 13210980F2004193 123.2 13210980F2004194 121 13210980F2004195 121 13210980F2004196 121.8 13210980F2004197 122.7 13210980F2004198 123.5 13210980F2004199 124.3 13210980F2004200 125.2 13210980F2004201 126 13210980F2004202 126 13210980F2004203 124.2 13210980F2004204 122.4 13210980F2004205 120.6 13210980F2004206 118.8 13210980F2004207 117 13210980F2004208 115.2 13210980F2004209 115 13210980F2004210 113.7 13210980F2004211 112.4 13210980F2004212 111.1 13210980F2004213 109.8

N. Middleton 2004 SiteID, Year, Day Q 13210824F2004186

33.4

13210824F2004187

33

13210824F2004188

33

13210824F2004189

32

13210824F2004190

31

13210824F2004191

30

13210824F2004192

29

13210824F2004193

28

13210824F2004194

27

13210824F2004195

27

13210824F2004196

28.2

13210824F2004197

29.3

13210824F2004198

30.5

13210824F2004199

31.7

13210824F2004200

32.8

13210824F2004201

34

13210824F2004202

34

13210824F2004203

33

13210824F2004204

32

13210824F2004205

31

13210824F2004206

30

13210824F2004207

29

13210824F2004208

28

13210824F2004209

28

13210824F2004210

27.7

13210824F2004211

27.4

13210824F2004212

27.1

13210824F2004213

26.8

S. Middleton 2004 SiteID, Year, Day Q 13210831F2004186 84.4 13210831F2004187 84 13210831F2004188 84 13210831F2004189 82.2 13210831F2004190 80.3 13210831F2004191 78.5 13210831F2004192 76.7 13210831F2004193 74.8 13210831F2004194 73 13210831F2004195 73 13210831F2004196 76 13210831F2004197 79 13210831F2004198 82 13210831F2004199 85 13210831F2004200 88 13210831F2004201 91 13210831F2004202 91 13210831F2004203 89.8 13210831F2004204 88.6 13210831F2004205 87.4 13210831F2004206 86.2 13210831F2004207 85 13210831F2004208 83.8 13210831F2004209 84 13210831F2004210 83.2 13210831F2004211 82.4 13210831F2004212 81.6 13210831F2004213 80.8

258

February 2009

Thurman 2004 SiteID, Year, Day 13209450W2004186 13209450W2004187 13209450W2004188 13209450W2004189 13209450W2004190 13209450W2004191 13209450W2004192 13209450W2004193 13209450W2004194 13209450W2004195 13209450W2004196 13209450W2004197 13209450W2004198 13209450W2004199 13209450W2004200 13209450W2004201 13209450W2004202 13209450W2004203 13209450W2004204 13209450W2004205 13209450W2004206 13209450W2004207 13209450W2004208 13209450W2004209 13209450W2004210 13209450W2004211 13209450W2004212 13209450W2004213

Q 18 18 18 17.7 17.3 17 16.7 16.3 16 16 16.2 16.3 16.5 16.7 16.8 17 17 17.3 17.6 17.9 18.2 18.5 18.8 19 19.3 19.6 19.9 20.2

Willow Creek 2004 SiteID, Year, Day Q 13210835F2004186 6.1 13210835F2004187 6 13210835F2004188 6 13210835F2004189 5.8 13210835F2004190 5.7 13210835F2004191 5.5 13210835F2004192 5.3 13210835F2004193 5.2 13210835F2004194 5 13210835F2004195 5 13210835F2004196 5.3 13210835F2004197 5.7 13210835F2004198 6 13210835F2004199 6.3 13210835F2004200 6.7 13210835F2004201 7 13210835F2004202 7 13210835F2004203 7.3 13210835F2004204 7.6 13210835F2004205 7.9 13210835F2004206 8.2 13210835F2004207 8.5 13210835F2004208 8.8 13210835F2004209 9 13210835F2004210 8.5 13210835F2004211 8 13210835F2004212 7.5 13210835F2004213 7

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Mason Drain 2004 SiteID, Year, Day Q 13210980F2004214 108.5 13210980F2004215 107.2 13210980F2004216 107 13210980F2004217 108.5 13210980F2004218 110 13210980F2004219 111.5 13210980F2004220 113 13210980F2004221 114.5 13210980F2004222 116 13210980F2004223 116 13210980F2004224 117.2 13210980F2004225 118.4 13210980F2004226 119.6 13210980F2004227 120.8 13210980F2004228 122 13210980F2004229 123.2 13210980F2004230 123 13210980F2004231 120.8 13210980F2004232 118.6 13210980F2004233 116.4 13210980F2004234 114.2 13210980F2004235 112 13210980F2004236 109.8 13210980F2004237 110 13210980F2004238 111.5 13210980F2004239 113 13210980F2004240 114.5 13210980F2004241 116

N. Middleton 2004 SiteID, Year, Day Q 13210824F2004214

26.5

13210824F2004215

26.2

13210824F2004216

26

13210824F2004217

25.7

13210824F2004218

25.4

13210824F2004219

25.1

13210824F2004220

24.8

13210824F2004221

24.5

13210824F2004222

24.2

13210824F2004223

24

13210824F2004224

24.7

13210824F2004225

25.4

13210824F2004226

26.1

13210824F2004227

26.8

13210824F2004228

27.5

13210824F2004229

28.2

13210824F2004230

28

13210824F2004231

28.5

13210824F2004232

29

13210824F2004233

29.5

13210824F2004234

30

13210824F2004235

30.5

13210824F2004236

31

13210824F2004237

31

13210824F2004238

30.3

13210824F2004239

29.6

13210824F2004240

28.9

13210824F2004241

28.2

S. Middleton 2004 SiteID, Year, Day Q 13210831F2004214 80 13210831F2004215 79.2 13210831F2004216 79 13210831F2004217 78.3 13210831F2004218 77.6 13210831F2004219 76.9 13210831F2004220 76.2 13210831F2004221 75.5 13210831F2004222 74.8 13210831F2004223 75 13210831F2004224 76 13210831F2004225 77 13210831F2004226 78 13210831F2004227 79 13210831F2004228 80 13210831F2004229 81 13210831F2004230 81 13210831F2004231 80.2 13210831F2004232 79.4 13210831F2004233 78.6 13210831F2004234 77.8 13210831F2004235 77 13210831F2004236 76.2 13210831F2004237 76 13210831F2004238 75.3 13210831F2004239 74.6 13210831F2004240 73.9 13210831F2004241 73.2

259

February 2009

Thurman 2004 SiteID, Year, Day 13209450W2004214 13209450W2004215 13209450W2004216 13209450W2004217 13209450W2004218 13209450W2004219 13209450W2004220 13209450W2004221 13209450W2004222 13209450W2004223 13209450W2004224 13209450W2004225 13209450W2004226 13209450W2004227 13209450W2004228 13209450W2004229 13209450W2004230 13209450W2004231 13209450W2004232 13209450W2004233 13209450W2004234 13209450W2004235 13209450W2004236 13209450W2004237 13209450W2004238 13209450W2004239 13209450W2004240 13209450W2004241

Q 20.5 20.8 21 20.5 20 19.5 19 18.5 18 18 18.8 19.6 20.4 21.2 22 22.8 23 22.5 22 21.5 21 20.5 20 20 19.4 18.8 18.2 17.6

Willow Creek 2004 SiteID, Year, Day Q 13210835F2004214 6.5 13210835F2004215 6 13210835F2004216 6 13210835F2004217 5.7 13210835F2004218 5.4 13210835F2004219 5.1 13210835F2004220 4.8 13210835F2004221 4.5 13210835F2004222 4.2 13210835F2004223 4 13210835F2004224 4.8 13210835F2004225 5.6 13210835F2004226 6.4 13210835F2004227 7.2 13210835F2004228 8 13210835F2004229 8.8 13210835F2004230 9 13210835F2004231 8.7 13210835F2004232 8.4 13210835F2004233 8.1 13210835F2004234 7.8 13210835F2004235 7.5 13210835F2004236 7.2 13210835F2004237 7 13210835F2004238 6.7 13210835F2004239 6.4 13210835F2004240 6.1 13210835F2004241 5.8

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Mason Drain 2004 SiteID, Year, Day Q 13210980F2004242 117.5 13210980F2004243 119 13210980F2004244 119 13210980F2004245 118 13210980F2004246 117 13210980F2004247 116 13210980F2004248 115 13210980F2004249 114 13210980F2004250 113 13210980F2004251 113 13210980F2004252 114.5 13210980F2004253 116 13210980F2004254 117.5 13210980F2004255 119 13210980F2004256 120.5 13210980F2004257 122 13210980F2004258 122 13210980F2004259 124.3 13210980F2004260 126.6 13210980F2004261 128.9 13210980F2004262 131.2 13210980F2004263 133.5 13210980F2004264 135.8 13210980F2004265 136 13210980F2004266 134.7 13210980F2004267 133.4 13210980F2004268 132.1 13210980F2004269 130.8

N. Middleton 2004 SiteID, Year, Day Q 13210824F2004242

27.5

13210824F2004243

26.8

13210824F2004244

27

13210824F2004245

27.3

13210824F2004246

27.6

13210824F2004247

27.9

13210824F2004248

28.2

13210824F2004249

28.5

13210824F2004250

28.8

13210824F2004251

29

13210824F2004252

28.7

13210824F2004253

28.4

13210824F2004254

28.1

13210824F2004255

27.8

13210824F2004256

27.5

13210824F2004257

27.2

13210824F2004258

27

13210824F2004259

28

13210824F2004260

29

13210824F2004261

30

13210824F2004262

31

13210824F2004263

32

13210824F2004264

33

13210824F2004265

33

13210824F2004266

37

13210824F2004267

37.2

13210824F2004268

37.4

13210824F2004269

37.6

S. Middleton 2004 SiteID, Year, Day Q 13210831F2004242 72.5 13210831F2004243 71.8 13210831F2004244 72 13210831F2004245 72.3 13210831F2004246 72.6 13210831F2004247 72.9 13210831F2004248 73.2 13210831F2004249 73.5 13210831F2004250 73.8 13210831F2004251 74 13210831F2004252 74.8 13210831F2004253 75.6 13210831F2004254 76.4 13210831F2004255 77.2 13210831F2004256 78 13210831F2004257 78.8 13210831F2004258 79 13210831F2004259 79.7 13210831F2004260 80.4 13210831F2004261 81.1 13210831F2004262 81.8 13210831F2004263 82.5 13210831F2004264 83.2 13210831F2004265 83 13210831F2004266 83.2 13210831F2004267 83.4 13210831F2004268 83.6 13210831F2004269 83.8

260

February 2009

Thurman 2004 SiteID, Year, Day 13209450W2004242 13209450W2004243 13209450W2004244 13209450W2004245 13209450W2004246 13209450W2004247 13209450W2004248 13209450W2004249 13209450W2004250 13209450W2004251 13209450W2004252 13209450W2004253 13209450W2004254 13209450W2004255 13209450W2004256 13209450W2004257 13209450W2004258 13209450W2004259 13209450W2004260 13209450W2004261 13209450W2004262 13209450W2004263 13209450W2004264 13209450W2004265 13209450W2004266 13209450W2004267 13209450W2004268 13209450W2004269

Q 17 17 17 17.2 17.4 17.6 17.8 18 18.2 18 17.7 17.4 17.1 16.8 16.5 16.2 16 16.7 17.4 18.1 18.8 19.5 20.2 20 20.2 20.4 20.6 20.8

Willow Creek 2004 SiteID, Year, Day Q 13210835F2004242 5.5 13210835F2004243 5.2 13210835F2004244 5 13210835F2004245 5.7 13210835F2004246 6.4 13210835F2004247 7.1 13210835F2004248 7.8 13210835F2004249 8.5 13210835F2004250 9.2 13210835F2004251 9 13210835F2004252 9.3 13210835F2004253 9.6 13210835F2004254 9.9 13210835F2004255 10.2 13210835F2004256 10.5 13210835F2004257 10.8 13210835F2004258 11 13210835F2004259 11.5 13210835F2004260 12 13210835F2004261 12.5 13210835F2004262 13 13210835F2004263 13.5 13210835F2004264 14 13210835F2004265 14 13210835F2004266 13.7 13210835F2004267 13.4 13210835F2004268 13.1 13210835F2004269 12.8

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Mason Drain 2004 SiteID, Year, Day Q 13210980F2004270 129.5 13210980F2004271 128.2 13210980F2004272 128 13210980F2004273 128.5 13210980F2004274 129 13210980F2004275 129.5 13210980F2004276 130 13210980F2004277 130.5 13210980F2004278 131 13210980F2004279 129.6 13210980F2004280 128.2 13210980F2004281 126.8 13210980F2004282 125.4 13210980F2004283 124 13210980F2004284 122.6 13210980F2004285 121.2 13210980F2004286 120.6 13210980F2004287 120 13210980F2004288 119.4 13210980F2004289 118.8 13210980F2004290 118.2 13210980F2004291 117.6 13210980F2004292 117 13210980F2004293 114.1 13210980F2004294 111.2 13210980F2004295 108.3 13210980F2004296 105.4 13210980F2004297 102.5

N. Middleton 2004 SiteID, Year, Day Q 13210824F2004270

37.8

13210824F2004271

38

13210824F2004272

37

13210824F2004273

36.8

13210824F2004274

36.6

13210824F2004275

36.4

13210824F2004276

36.2

13210824F2004277

36

13210824F2004278

35.8

13210824F2004279

35.1

13210824F2004280

34.4

13210824F2004281

33.7

13210824F2004282

33

13210824F2004283

32.3

13210824F2004284

31.6

13210824F2004285

30.9

13210824F2004286

30.3

13210824F2004287

29.7

13210824F2004288

29.1

13210824F2004289

28.5

13210824F2004290

27.9

13210824F2004291

27.3

13210824F2004292

26.7

13210824F2004293

26.2

13210824F2004294

25.7

13210824F2004295

25.2

13210824F2004296

24.7

13210824F2004297

24.2

S. Middleton 2004 SiteID, Year, Day Q 13210831F2004270 84 13210831F2004271 84.2 13210831F2004272 84 13210831F2004273 82.8 13210831F2004274 81.6 13210831F2004275 80.4 13210831F2004276 79.2 13210831F2004277 78 13210831F2004278 76.8 13210831F2004279 76.4 13210831F2004280 76 13210831F2004281 75.6 13210831F2004282 75.2 13210831F2004283 74.8 13210831F2004284 74.4 13210831F2004285 74 13210831F2004286 73 13210831F2004287 72 13210831F2004288 71 13210831F2004289 70 13210831F2004290 69 13210831F2004291 68 13210831F2004292 67 13210831F2004293 66.6 13210831F2004294 66.2 13210831F2004295 65.8 13210831F2004296 65.4 13210831F2004297 65

261

February 2009

Thurman 2004 SiteID, Year, Day 13209450W2004270 13209450W2004271 13209450W2004272 13209450W2004273 13209450W2004274 13209450W2004275 13209450W2004276 13209450W2004277 13209450W2004278 13209450W2004279 13209450W2004280 13209450W2004281 13209450W2004282 13209450W2004283 13209450W2004284 13209450W2004285 13209450W2004286 13209450W2004287 13209450W2004288 13209450W2004289 13209450W2004290 13209450W2004291 13209450W2004292 13209450W2004293 13209450W2004294 13209450W2004295 13209450W2004296 13209450W2004297

Q 21 21.2 21 20.3 19.6 18.9 18.2 17.5 16.8 16.7 16.6 16.5 16.4 16.3 16.2 16.1 15.8 15.5 15.2 14.9 14.6 14.3 14 14.3 14.6 14.9 15.2 15.5

Willow Creek 2004 SiteID, Year, Day Q 13210835F2004270 12.5 13210835F2004271 12.2 13210835F2004272 12 13210835F2004273 13 13210835F2004274 14 13210835F2004275 15 13210835F2004276 16 13210835F2004277 17 13210835F2004278 18 13210835F2004279 16.9 13210835F2004280 15.8 13210835F2004281 14.7 13210835F2004282 13.6 13210835F2004283 12.5 13210835F2004284 11.4 13210835F2004285 10.3 13210835F2004286 9.8 13210835F2004287 9.3 13210835F2004288 8.8 13210835F2004289 8.3 13210835F2004290 7.8 13210835F2004291 7.3 13210835F2004292 6.8 13210835F2004293 6.4 13210835F2004294 6 13210835F2004295 5.6 13210835F2004296 5.2 13210835F2004297 4.8

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Mason Drain 2004 SiteID, Year, Day Q 13210980F2004298 99.6 13210980F2004299 96.7 13210980F2004300 96.8 13210980F2004301 96.9 13210980F2004302 97 13210980F2004303 97.1 13210980F2004304 97.1 13210980F2004305 97.1

N. Middleton 2004 SiteID, Year, Day Q 13210824F2004298

23.7

13210824F2004299

23.2

13210824F2004300

23.2

13210824F2004301

23.2

13210824F2004302

23.2

13210824F2004303

23.2

13210824F2004304

23.2

13210824F2004305 SiteID = Site Identification number; Q = discharge

23.2

S. Middleton 2004 SiteID, Year, Day Q 13210831F2004298 64.6 13210831F2004299 64.2 13210831F2004300 64.2 13210831F2004301 64.2 13210831F2004302 64.2 13210831F2004303 64.2 13210831F2004304 64.2 13210831F2004305 64.2

262

February 2009

Thurman 2004 SiteID, Year, Day 13209450W2004298 13209450W2004299 13209450W2004300 13209450W2004301 13209450W2004302 13209450W2004303 13209450W2004304 13209450W2004305

Q 15.8 16.1 16.1 16.1 16.1 16.1 16.1 16.1

Willow Creek 2004 SiteID, Year, Day Q 13210835F2004298 4.4 13210835F2004299 4 13210835F2004300 4 13210835F2004301 4 13210835F2004302 4 13210835F2004303 4 13210835F2004304 4 13210835F2004305 4

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table C-13. Water temperature data (abridged) in degrees Celsius used to create Lower Boise River Mainstem Tributary Temperature Analysis Data Summary and Technical Report, June 2005. Data provided by the City of Boise, January 2009. Lower Boise River Drain and Tributary Abridged Water Temperature (*C) Data Day 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004

Time 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52

Willow up 14.94 14.94 14.94 14.79 14.79 14.79 14.63 14.47 14.47 14.32 14.32 14.16 14.01 14.01 13.85 13.85 13.7 13.7 13.7 13.54 13.54 13.54 13.54 13.39 13.39 13.39 13.24 13.24 13.08

Willow dn 15.41 15.56 15.56 15.56 15.56 15.41 15.41 15.24 15.24 15.08 14.93 14.77 14.61 14.45 14.29 14.14 13.98 13.98 13.83 13.83 13.83 13.67 13.67 13.52 13.37 13.21 13.06 12.9 12.74

Mill up

Mill dn 14.61 14.3 13.99 13.68 13.53 13.22 13.07 12.76 12.6 12.44 12.44 12.76 12.91 13.07 12.91 12.91 12.91 12.91 12.91 12.76 12.6 12.44 12.13 11.98 11.82 11.67 11.51 11.36 11.21

Fifteenmile up 15.49 15.34 15.02 14.7 14.38 14.07 13.76 13.61 13.3 13.14 12.99 12.83 12.83 12.83 12.83 12.83 12.83 12.83 12.83 12.83 12.68 12.68 12.52 12.37 12.06 11.9 11.74 10.51 10.35

Fifteenmile dn 14.68 14.05 13.59 13.28 12.97 12.66 12.35 12.2 11.89 11.73 11.73 11.89 12.2 12.35 12.35 12.35 12.51 12.51 12.51 12.35 12.2 11.89 11.58 11.42 11.11 10.96 10.65 10.49 10.34

263

Caldwell dn 15.98 15.67 15.36 15.04 14.72 14.41 14.1 13.79 13.48 13.33 13.33 13.33 13.33 13.33 13.33 13.33 13.33 13.33 13.33 13.18 13.02 12.87 12.71 12.56 12.24 12.09 11.93 11.78 11.62

Caldwell up 15.88 15.72 15.41 15.09 14.77 14.3 14.14 13.84 13.53 13.38 13.38 13.22 13.38 13.22 13.38 13.38 13.38 13.38 13.22 13.07 12.92 12.76 12.61 12.45 12.29 12.14 11.83 11.68 11.52

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004

Time 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52

Willow up 13.08 12.93 12.93 12.77 12.77 12.62 12.62 12.46 12.46 12.31 12.31 12.31 12.31 12.31 12.31 12.31 12.31 12.31 12.46 12.46 12.46 12.46 12.62 12.62 12.62 12.62 12.62 12.62 12.62 12.46 12.46 12.46

Willow dn 12.59 12.43 12.28 12.12 12.12 11.97 11.81 11.66 11.66 11.66 11.66 11.66 11.81 11.97 12.12 12.28 12.59 12.74 12.9 12.9 12.9 12.9 12.9 12.74 12.74 12.74 12.59 12.59 12.43 12.43 12.28 12.28

Mill up

Mill dn 11.05 10.89 10.74 10.74 10.74 10.89 11.05 11.36 11.82 11.98 12.44 13.07 13.22 13.37 13.37 13.37 13.22 12.91 12.6 12.44 12.13 11.98 11.82 11.51 11.36 11.21 11.05 10.89 10.89 10.89 11.05 11.36

Fifteenmile up 10.19 10.19 10.04 9.88 9.88 9.88 10.04 10.51 10.97 11.43 11.9 12.37 12.83 13.14 13.3 13.3 13.14 12.83 12.52 12.21 11.74 11.43 11.13 10.97 10.66 10.51 10.35 10.19 10.04 10.19 10.35 10.51

Fifteenmile dn 10.18 10.03 9.87 9.87 9.72 9.87 10.03 10.49 10.96 11.42 11.89 12.51 12.82 13.13 13.28 13.28 13.13 12.82 12.51 12.04 11.73 11.42 11.11 10.81 10.65 10.49 10.18 10.18 10.03 10.03 10.34 10.49

264

Caldwell dn 11.31 11.16 11.01 11.01 11.01 11.16 11.31 11.62 11.93 12.4 12.71 13.18 13.33 13.48 13.48 13.48 13.33 13.18 13.18 12.87 12.71 12.56 12.24 12.09 11.78 11.62 11.47 11.31 11.31 11.31 11.47 11.93

February 2009

Caldwell up 11.37 11.22 11.06 10.91 10.91 11.06 11.37 11.68 11.98 12.45 12.76 13.07 13.38 13.53 13.53 13.38 13.38 13.22 13.07 12.92 12.76 12.45 12.29 12.14 11.83 11.68 11.52 11.37 11.37 11.37 11.52 11.83

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004

Time 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52

Willow up 12.31 12.31 12.31 12.31 12.31 12.15 12.31 12.31 12.31 12.46 12.46 12.62 12.77 12.77 12.77 12.77 12.77 12.77 12.77 12.77 12.62 12.62 12.46 12.46 12.31 12.31 12.15 12.15 12.15 12.15 12.15 12.31

Willow dn 12.12 12.12 11.97 11.97 12.12 12.12 12.12 12.28 12.43 12.43 12.59 12.74 12.9 12.9 12.9 12.9 12.74 12.74 12.59 12.59 12.43 12.12 11.97 11.81 11.66 11.66 11.66 11.66 11.66 11.81 12.12 12.43

Mill up

Mill dn 12.13 12.76 13.07 13.37 13.99 14.3 14.3 14.14 13.83 13.53 13.22 12.91 12.6 12.13 11.82 11.51 11.21 10.89 10.58 10.43 10.43 10.74 11.21 11.98 12.76 13.68 14.46 15.24 15.72 15.88 15.88 15.72

Fifteenmile up 11.28 12.06 12.68 13.14 13.61 14.07 14.23 14.23 13.92 13.46 12.99 12.68 12.37 11.9 11.43 11.13 10.66 10.35 10.04 9.72 9.72 9.88 10.19 10.97 11.9 12.83 13.92 14.7 15.34 15.66 15.97 15.97

Fifteenmile dn 11.42 12.2 12.82 13.28 13.89 14.21 14.36 14.21 13.89 13.28 12.97 12.51 12.04 11.58 11.27 10.81 10.49 10.03 9.72 9.41 9.41 9.72 10.18 10.96 12.04 12.97 14.05 14.99 15.47 15.78 16.1 16.1

265

Caldwell dn 12.24 12.71 12.71 13.18 13.79 13.94 14.1 14.1 14.1 13.94 13.63 13.33 13.18 12.71 12.4 12.09 11.62 11.31 11.01 10.85 10.85 11.16 11.62 12.24 12.87 13.63 14.41 15.04 15.67 15.98 15.98 15.98

February 2009

Caldwell up 12.29 12.61 12.76 13.22 13.84 13.84 13.99 14.14 13.99 13.84 13.68 13.38 13.07 12.76 12.45 11.98 11.68 11.37 11.06 10.91 10.91 11.22 11.52 12.14 12.92 13.68 14.3 15.09 15.57 15.88 15.88 15.88

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 5/13/2004 5/13/2004 5/13/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004

Time 21:52 22:52 23:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52 13:52 14:52 15:52

Willow up 12.46 12.62 12.77 13.7 13.54 13.54 13.39 13.39 13.39 13.24 13.24 13.24 13.24 13.24 13.24 13.24 13.24 13.39 13.39 13.39 13.24 13.24 13.24 13.24 13.08 13.08 12.93 12.93 12.93 12.77 12.77 12.77

Willow dn 12.59 12.74 13.06 14.14 13.98 13.83 13.67 13.52 13.52 13.37 13.37 13.37 13.37 13.37 13.37 13.37 13.37 13.52 13.52 13.52 13.52 13.52 13.37 13.37 13.21 13.21 13.21 13.21 13.06 13.06 12.9 12.74

Mill up

Mill dn 15.56 15.24 14.77 13.07 13.37 13.68 13.83 13.99 14.14 14.14 14.14 14.14 13.99 13.83 13.68 13.53 13.37 13.07 12.91 12.76 12.44 12.13 11.82 11.67 11.67 11.82 12.44 12.76 13.37 14.3 14.93 15.56

Fifteenmile up 15.81 15.49 14.86 12.37 12.83 13.14 13.46 13.76 14.07 14.07 14.23 14.07 14.07 13.92 13.61 13.3 12.99 12.83 12.52 12.37 12.06 11.74 11.43 11.28 11.28 11.28 11.59 12.06 12.68 13.61 14.38 15.18

Fifteenmile dn 15.78 15.47 14.83 12.2 12.82 13.13 13.43 13.74 14.05 14.05 14.21 14.05 14.05 13.74 13.59 13.28 12.97 12.66 12.51 12.35 12.04 11.73 11.42 11.27 11.11 11.27 11.58 12.04 12.66 13.59 14.36 14.99

266

Caldwell dn 15.83 15.67 15.36 13.48 13.63 13.94 14.1 14.26 14.41 14.41 14.57 14.57 14.57 14.41 14.26 14.1 13.94 13.79 13.48 13.33 13.02 12.71 12.56 12.4 12.24 12.24 12.4 12.71 13.18 13.79 14.41 14.88

February 2009

Caldwell up 15.88 15.57 15.41 13.38 13.68 13.84 13.99 14.14 14.3 14.46 14.61 14.46 14.46 14.3 14.3 14.14 13.99 13.68 13.53 13.38 13.07 12.76 12.61 12.29 12.14 12.14 12.45 12.76 13.22 13.68 14.3 14.93

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004

Time 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52

Willow up 12.77 12.77 12.77 12.93 12.93 13.08 13.24 13.39 13.39 13.54 13.54 13.7 13.7 13.7 13.7 13.7 13.7 13.54 13.54 13.54 13.39 13.39 13.24 13.24 13.24 13.24 13.24 13.39 13.39 13.54 13.54 13.7

Willow dn 12.74 12.74 12.9 12.9 13.06 13.21 13.37 13.52 13.67 13.83 13.83 13.98 13.98 14.14 14.14 13.98 13.98 13.98 13.83 13.83 13.67 13.67 13.52 13.52 13.52 13.37 13.52 13.52 13.52 13.67 13.67 13.83

Mill up

Mill dn 16.03 16.35 16.51 16.51 16.19 15.88 15.4 15.08 14.61 14.14 13.83 13.37 13.07 12.76 12.44 12.13 12.13 12.29 12.6 13.37 13.99 14.61 14.93 15.08 15.56 15.56 15.56 15.4 15.24 15.08 14.77 14.46

Fifteenmile up 15.66 16.13 16.44 16.44 16.29 15.81 15.49 14.86 14.38 13.76 13.3 12.99 12.52 12.21 11.74 11.43 11.43 11.43 11.74 12.37 12.99 13.76 14.38 14.86 15.49 15.81 15.81 15.49 15.34 15.02 14.54 14.07

Fifteenmile dn 15.63 16.1 16.42 16.42 16.26 15.78 15.31 14.83 14.21 13.74 13.28 12.97 12.51 12.04 11.73 11.42 11.42 11.42 11.73 12.35 13.13 13.74 14.36 14.99 15.47 15.63 15.63 15.47 15.31 14.99 14.52 14.05

267

Caldwell dn 15.51 15.98 16.3 16.3 16.3 16.3 16.14 15.83 15.51 15.19 14.88 14.41 14.1 13.79 13.33 13.02 12.87 12.87 13.02 13.33 13.94 14.57 14.88 15.19 15.67 15.67 15.83 15.83 15.67 15.67 15.36 15.19

February 2009

Caldwell up 15.57 15.88 16.2 16.36 16.36 16.2 16.04 15.88 15.57 15.25 14.77 14.46 14.14 13.68 13.38 13.07 12.92 12.76 12.92 13.38 13.84 14.46 14.93 15.25 15.57 15.72 15.72 15.72 15.72 15.57 15.41 15.25

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/19/2004 5/19/2004 5/19/2004 5/19/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004

Time 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 5:52 6:52 7:52 8:52

Willow up 13.7 13.85 13.85 13.85 13.85 13.85 13.85 13.85 13.85 13.85 13.7 13.7 13.7 13.7 13.54 13.54 13.54 13.54 13.54 13.54 13.54 13.7 13.7 13.7 13.7 13.7 13.7 13.7 14.63 14.63 14.63 14.63

Willow dn 13.83 13.98 13.98 13.98 14.14 14.14 14.14 14.14 14.14 14.14 13.98 13.98 13.98 13.98 13.83 13.83 13.67 13.67 13.83 13.83 13.83 13.83 13.83 13.98 13.98 13.98 13.98 14.14 14.77 14.77 14.77 14.77

Mill up

Mill dn 14.14 13.99 13.68 13.53 13.37 13.07 12.91 12.76 12.76 12.76 12.91 13.07 13.53 14.14 14.61 14.77 14.93 14.93 14.93 14.93 14.77 14.46 14.3 13.99 13.68 13.37 13.22 13.07 13.83 13.68 13.68 13.68

Fifteenmile up 13.76 13.46 13.14 12.99 12.68 12.52 12.37 12.21 12.21 12.21 12.37 12.52 12.99 13.46 14.07 14.23 14.38 14.23 14.23 14.07 13.76 13.46 13.14 12.99 12.68 12.52 12.37 12.21 13.3 13.14 12.99 12.99

Fifteenmile dn 13.74 13.43 13.13 12.82 12.66 12.51 12.35 12.2 12.2 12.2 12.35 12.51 12.97 13.43 14.05 14.21 14.36 14.21 14.21 14.05 13.74 13.43 13.13 12.82 12.66 12.51 12.35 12.2 13.13 12.97 12.82 12.82

268

Caldwell dn 15.04 14.72 14.41 14.26 14.1 13.79 13.63 13.48 13.33 13.18 13.33 13.33 13.63 14.1 14.41 14.72 15.04 15.04 15.19 15.19 15.04 14.88 14.72 14.57 14.26 14.1 13.79 13.48 14.72 14.41 14.26 14.26

February 2009

Caldwell up 14.93 14.77 14.46 14.3 13.99 13.84 13.68 13.38 13.38 13.22 13.22 13.22 13.68 13.99 14.46 14.77 14.93 15.09 15.09 15.09 15.09 14.93 14.61 14.46 14.3 13.99 13.84 13.53 14.61 14.46 14.3 14.3

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004

Time 9:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52

Willow up 14.63 14.47 14.47 14.47 14.32 14.32 14.32 14.32 14.32 14.32 14.32 14.32 14.32 14.32 14.32 14.32 14.32 14.32 14.32 14.32 14.32 14.32 14.32 14.32 14.32 14.32 14.32 14.16 14.16 14.16 14.16 14.16

Willow dn 14.77 14.77 14.77 14.77 14.77 14.77 14.77 14.77 14.77 14.77 14.77 14.77 14.77 14.77 14.77 14.61 14.61 14.61 14.61 14.61 14.61 14.61 14.61 14.45 14.61 14.61 14.61 14.61 14.61 14.61 14.61 14.61

Mill up

Mill dn 13.99 14.3 14.61 15.24 15.24 15.24 15.24 15.4 15.4 15.4 15.56 15.4 15.24 15.08 14.93 14.77 14.61 14.3 14.14 13.99 13.83 13.83 13.68 13.53 13.53 13.37 13.83 13.99 14.3 14.77 14.61 15.08

Fifteenmile up 13.14 13.3 13.76 14.38 14.7 15.18 15.34 15.49 15.49 15.49 15.34 15.18 15.02 14.86 14.54 14.23 14.07 13.92 13.76 13.61 13.61 13.46 13.3 13.3 13.14 12.99 13.3 13.46 13.92 14.38 14.38 14.86

Fifteenmile dn 13.13 13.43 13.74 14.52 14.83 15.15 15.47 15.47 15.63 15.47 15.31 15.15 14.83 14.68 14.52 14.21 14.05 13.74 13.59 13.59 13.43 13.43 13.28 13.28 13.13 12.97 13.28 13.43 13.74 14.36 14.36 14.83

269

Caldwell dn 14.41 14.57 14.88 15.36 15.36 15.67 15.67 15.67 15.83 15.98 15.98 15.98 15.83 15.67 15.67 15.36 15.19 15.04 14.72 14.57 14.41 14.26 14.1 13.94 13.94 13.79 13.94 14.1 14.41 14.72 14.72 15.04

February 2009

Caldwell up 14.3 14.61 14.77 15.25 15.41 15.57 15.72 15.72 15.88 15.88 16.04 16.04 15.88 15.88 15.57 15.41 15.25 14.93 14.77 14.61 14.46 14.3 14.14 13.99 13.84 13.84 13.99 14.14 14.46 14.77 14.77 15.09

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 6/29/2004 6/29/2004 6/29/2004 6/29/2004 6/29/2004 6/29/2004 6/29/2004 6/29/2004 6/29/2004 6/29/2004 6/29/2004 6/29/2004 6/29/2004

Time 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52

Willow up 14.16 14.16 14.01 14.16 14.16 14.16 14.16 14.16 14.16 14.16 14.16 14.16 14.16 14.16 14.01 14.01 13.85 13.85 13.85 19.92 20.08 20.4 20.73 21.22 21.89 22.39 22.72 22.72 22.39 21.89 21.56 21.22

Willow dn 14.61 14.45 14.45 14.29 14.14 14.14 13.98 13.83 13.67 13.67 13.52 13.52 13.52 13.52 13.52 13.52 13.52 13.52 13.52 21.22 20.72 20.23 19.91 19.58 19.09 18.77 18.44 18.12 17.79 18.12 18.44 18.93

Mill up

18.33 18.82 19.31 19.96 20.44 20.77 20.77 20.44 20.12 19.96 19.63 19.31 19.14

Mill dn 15.24 15.24 15.24 15.08 14.77 14.61 14.3 13.99 13.68 13.37 13.07 12.76 12.44 12.13 11.98 11.98 12.13 12.29 12.76 18.59 19.08 19.73 20.22 20.71 20.71 20.38 20.06 20.06 19.73 19.41 19.24 18.92

Fifteenmile up 15.02 15.02 14.86 14.7 14.54 14.23 13.92 13.61 13.3 12.83 12.52 12.21 11.74 11.43 11.28 11.28 11.43 11.59 12.06 18.05 18.7 19.51 20.32 21.31 21.81 22.14 21.81 21.48 20.98 20.48 19.83 19.34

Fifteenmile dn 14.99 14.99 14.83 14.68 14.36 14.21 13.89 13.59 13.13 12.82 12.51 12.2 11.73 11.42 11.27 11.27 11.27 11.58 12.04 18.01 18.66 19.47 20.28 21.26 21.76 22.09 21.76 21.42 20.93 20.44 19.79 19.31

270

Caldwell dn 15.36 15.36 15.36 15.36 15.19 14.88 14.57 14.26 14.1 13.79 13.48 13.18 13.02 12.71 12.56 12.4 12.4 12.56 12.87 18.54 18.87 19.35 19.83 20.48 21.14 21.31 21.14 20.98 20.64 20.32 19.99 19.67

February 2009

Caldwell up 15.25 15.41 15.41 15.25 15.09 14.93 14.61 14.3 13.99 13.84 13.53 13.22 12.92 12.76 12.45 12.29 12.29 12.45 12.76 18.59 18.91 19.39 19.88 20.53 21.18 21.35 21.02 20.86 20.69 20.37 20.04 19.72

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 6/29/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/20/2004 7/20/2004 7/20/2004 7/20/2004 7/20/2004

Time 23:52 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52

Willow up 20.73 20.4 19.92 19.76 19.27 19.11 18.62 18.29 18.29 18.46 18.62 18.94 19.59 20.56 21.72 22.72 23.73 24.6 25.12 25.47 25.82 24.95 24.26 23.73 23.22 22.89 22.56 22.22 21.89 21.56 21.22

Willow dn 19.58 20.39 21.55 22.39 23.23 23.92 24.27 23.74 23.23 22.72 22.22 21.88 21.55 20.23 21.38 22.39 23.4 24.44 24.96 25.48 25.83 24.96 24.27 23.74 23.4 22.89 22.56 22.22 21.88 21.72 21.38 21.05

Mill up 18.82 18.49 18.33 18.01 17.69 17.37 17.06 16.74 16.58 16.58 16.58 16.89 17.37 17.85 19.14 19.63 20.12 20.44 20.77 21.09 21.26 21.26 21.09 21.09 20.77 20.77 20.44 20.28 19.96 19.79 19.63 19.31

Mill dn 18.59 18.43 18.11 17.79 17.47 17.15 16.83 16.51 16.51 16.67 16.83 17.31 17.79 18.27 19.57 20.06 20.22 20.71 21.03 21.36 21.19 21.19 21.03 20.87 20.71 20.54 20.22 20.06 19.89 19.57 19.24 19.08

Fifteenmile up 18.86 18.37 17.89 17.41 17.08 16.61 16.29 15.97 15.81 15.81 15.97 16.29 17.08 17.73 18.86 19.67 20.65 21.31 21.98 22.65 23.16 22.98 22.65 22.31 21.98 21.48 21.14 20.65 20.32 19.99 19.67 19.51

Fifteenmile dn 18.82 18.33 17.85 17.37 17.05 16.57 16.26 15.94 15.78 15.78 15.94 16.26 17.05 17.85 18.82 19.63 20.6 21.26 21.92 22.59 23.09 22.93 22.76 22.42 21.92 21.42 21.09 20.6 20.28 19.96 19.63 19.47

271

Caldwell dn 19.35 19.03 18.71 18.38 18.06 17.74 17.58 17.26 17.09 16.94 16.94 17.26 17.58 18.06 19.19 19.67 20.32 20.64 21.14 21.81 22.14 21.98 21.98 21.81 21.64 21.48 21.14 20.98 20.64 20.48 20.16 19.99

February 2009

Caldwell up 19.39 19.07 18.75 18.43 18.11 17.78 17.46 17.31 16.99 16.99 16.99 17.14 17.62 18.11 19.07 19.56 20.21 20.69 21.18 21.68 22.01 22.01 22.01 21.84 21.68 21.35 21.18 20.86 20.69 20.37 20.21 20.04

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 7/20/2004 7/20/2004 7/20/2004 7/20/2004 7/20/2004 7/20/2004 7/20/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004

Time 5:52 6:52 7:52 8:52 9:52 10:52 11:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52

Willow up 20.89 20.56 20.24 20.08 19.92 20.24 21.06 22.08 22.58 22.75 22.75 22.92 23.26 23.26 23.42 23.26 23.08 22.75 22.42 22.08 21.92 21.92 21.75 21.75 21.41 21.24 21.08 21.08 20.91 20.91 20.74 20.91

Willow dn 20.56 20.23 20.07 19.91 20.23 20.72 21.72 20.38 20.71 20.87 21.2 21.37 21.71 21.87 22.04 21.87 21.71 21.37 21.2 21.03 21.03 20.87 20.54 20.38 20.22 20.06 19.9 19.9 19.74 19.74 19.74 19.58

Mill up 19.14 18.82 18.82 18.66 18.82 19.14 19.63 19.96 20.12 20.28 20.6 20.77 20.93 20.93 20.93 20.77 20.77 20.6 20.44 20.12 20.12 19.96 19.79 19.63 19.63 19.47 19.31 19.14 19.14 18.98 18.98 18.98

Mill dn 18.92 18.76 18.76 18.76 19.08 19.57 20.06 19.56 19.56 19.56 19.56 19.56 19.72 19.72 19.88 19.88 20.04 20.04 20.04 20.04 20.04 20.04 20.04 19.88 19.88 19.88 19.72 19.72 19.56 19.56 19.39 19.39

Fifteenmile up 19.18 18.86 18.7 18.7 18.7 19.02 19.51 20.13 20.45 20.78 21.28 21.61 21.78 22.11 22.28 22.28 21.94 21.61 21.28 20.94 20.78 20.45 20.29 19.97 19.64 19.48 19.32 19.16 19.16 18.99 18.99 19.16

Fifteenmile dn 19.14 18.82 18.66 18.66 18.66 18.98 19.47 20.23 20.39 20.88 21.21 21.54 21.88 22.04 22.21 22.21 21.88 21.71 21.38 21.04 20.72 20.55 20.23 19.91 19.74 19.42 19.42 19.26 19.09 19.09 19.09 19.09

272

Caldwell dn 19.83 19.51 19.35 19.35 19.35 19.51 19.83 20.48 20.81 21.14 21.31 21.48 21.64 21.98 21.98 21.81 21.64 21.48 21.31 21.14 20.98 20.81 20.48 20.48 20.32 20.16 19.99 19.83 19.67 19.67 19.67 19.67

February 2009

Caldwell up 19.72 19.56 19.39 19.23 19.39 19.56 19.72 20.38 20.71 20.87 21.2 21.37 21.71 21.87 22.04 21.87 21.71 21.37 21.2 21.03 21.03 20.87 20.54 20.38 20.22 20.06 19.9 19.9 19.74 19.74 19.74 19.58

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/23/2004 8/23/2004

Time 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52

Willow up 20.91 21.08 21.75 22.42 22.58 22.92 23.08 22.92 22.75 22.42 22.25 22.08 20.58 20.42 20.26 20.09 20.09 20.26 20.42 20.58 20.58 20.42 20.26 20.09 20.09 19.77 19.61 19.29 19.13 18.97 18.97 18.97

Willow dn 19.74 20.06 20.22 20.71 20.87 21.2 21.2 21.2 21.2 20.87 20.87 20.54 20.06 19.74 19.58 19.58 19.42 19.42 19.58 19.58 19.74 19.58 19.58 19.42 19.42 19.26 19.09 18.93 18.77 18.45 18.29 18.13

Mill up 18.98 19.47 19.79 20.28 20.6 20.77 20.77 20.77 20.6 20.28 20.12 20.12 18.82 18.66 18.66 18.66 18.66 18.66 18.82 18.82 18.98 18.82 18.82 18.49 18.49 18.33 18.17 17.85 17.85 17.69 17.53 17.37

Mill dn 19.39 19.23 19.23 19.23 19.23 19.39 19.56 19.56 19.72 19.72 19.88 19.88 19.56 19.56 19.39 19.39 19.23 19.23 19.23 19.06 19.06 19.06 19.06 19.06 19.06 18.9 18.9 18.9 18.74 18.74 18.74 18.57

Fifteenmile up 19.16 19.48 19.97 20.45 20.94 21.11 21.28 21.44 21.44 21.28 21.11 20.94 18.99 18.67 18.51 18.51 18.51 18.67 18.67 18.83 18.99 19.16 19.16 18.99 18.99 18.67 18.51 18.34 18.02 17.86 17.54 17.38

Fifteenmile dn 19.09 19.42 19.91 20.39 20.88 21.21 21.38 21.38 21.38 21.38 21.04 20.88 18.93 18.77 18.6 18.6 18.44 18.6 18.77 18.93 19.09 19.09 19.09 18.93 18.93 18.6 18.44 18.28 17.96 17.79 17.63 17.48

273

Caldwell dn 19.83 20.16 20.32 20.81 21.14 21.31 21.31 21.31 21.14 20.98 20.81 20.64 19.99 19.83 19.67 19.51 19.51 19.51 19.51 19.67 19.67 19.67 19.67 19.51 19.51 19.35 19.19 18.87 18.71 18.54 18.38 18.22

February 2009

Caldwell up 19.74 20.06 20.22 20.71 20.87 21.2 21.2 21.2 21.2 20.87 20.87 20.54 20.06 19.74 19.58 19.58 19.42 19.42 19.58 19.58 19.74 19.58 19.58 19.42 19.42 19.26 19.09 18.93 18.77 18.45 18.29 18.13

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 8/23/2004 8/23/2004 8/23/2004 8/23/2004 8/23/2004 8/23/2004 8/23/2004 8/23/2004 8/23/2004 8/23/2004

Time 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52

Willow up 18.64 18.48 18.32 18.16 17.99 17.83 17.83 17.83 18.16 18.64

Willow dn 17.97 17.81 17.64 17.48 17.33 17.17 17.01 17.01 17.01 17.33

Day 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004

Time 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52

Notus dn 15.98 15.82 15.5 15.34 15.18 15.03 14.71 14.56 14.24 14.24 14.24 14.08 13.93 13.93 13.77 13.77 13.77 13.62 13.46

Notus up 15.88 15.72 15.56 15.41 15.24 14.92 14.77 14.45 14.29 14.14 14.14 13.98 13.83 13.83 13.83 13.83 13.68 13.52 13.37

Mill up 17.21 17.06 16.89 16.89 16.74 16.58 16.58 16.58 16.74 17.06

Mill dn 18.57 18.41 18.41 18.25 18.09 18.09 17.93 17.77 17.77 17.77

Fifteenmile up 17.22 17.06 16.9 16.74 16.58 16.42 16.27 16.42 16.58 17.06

Indian up 15.71 15.39 15.07 14.74 14.43 14.12 13.96 13.66 13.5 13.34 13.34 13.34 13.34 13.34 13.34 13.34 13.34 13.34 13.34

Indian dn 15.68 15.36 15.04 14.73 14.41 14.26 13.94 13.79 13.48 13.33 13.33 13.33 13.33 13.33 13.33 13.48 13.48 13.48 13.33

Dixie up 16.88 16.4 15.92 15.45 15.13 14.66 14.34 14.03 13.72 13.42 13.26 13.26 13.26 13.26 13.42 13.57 13.57 13.57 13.57

Fifteenmile dn 17.16 17 16.84 16.68 16.52 16.37 16.37 16.37 16.68 17

Dixie dn 16.91 16.43 15.96 15.49 15.01 14.69 14.38 13.92 13.76 13.46 13.3 13.3 13.3 13.46 13.46 13.61 13.61 13.61 13.61

Mason up 14.81 14.49 14.18 13.87 13.41 13.1 12.94 12.63 12.48 12.32 12.32 12.48 12.63 12.79 12.79 12.79 12.79 12.63 12.63

274

February 2009

Caldwell dn 18.06 17.9 17.58 17.42 17.26 17.09 17.09 17.09 17.09 17.58

Mason dn 13.01 12.7 12.54 12.39 12.54 12.54 12.7 12.7 12.86 12.86 12.7 12.7 12.7 12.54 12.39 12.08 11.92 11.61 11.46

Caldwell up 17.97 17.81 17.64 17.48 17.33 17.17 17.01 17.01 17.01 17.33

Conway up 14.63 14.32 14.01 13.71 13.4 13.24 13.09 12.78 12.63 12.63 12.78 12.78 12.94 12.94 12.94 13.09 13.24 13.4 13.24

Conway dn 14.62 14.3 13.99 13.83 13.53 13.37 13.06 12.91 12.75 12.59 12.75 12.75 12.91 12.91 12.91 13.06 13.22 13.37 13.22

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/10/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/11/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004

Time 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52

Notus dn 13.31 13.15 12.84 12.84 12.68 12.53 12.37 12.22 12.22 12.07 11.91 11.76 11.6 11.6 11.76 11.76 11.91 12.37 12.68 12.99 13.46 13.62 13.77 13.77 13.62 13.46 13.31 13.15 12.99 12.84 12.84 12.84 12.68

Notus up 13.37 13.06 12.91 12.75 12.59 12.44 12.28 12.13 12.13 11.97 11.82 11.66 11.66 11.66 11.66 11.66 11.82 12.28 12.44 12.75 13.22 13.52 13.68 13.68 13.52 13.37 13.22 13.06 12.91 12.91 12.75 12.75 12.75

Indian up 13.34 13.19 12.88 12.72 12.57 12.41 12.25 12.09 11.78 11.78 11.63 11.47 11.32 11.32 11.32 11.47 11.63 12.09 12.25 12.72 13.03 13.5 13.81 13.96 13.96 13.96 13.81 13.66 13.34 13.19 13.03 12.72 12.57

Indian dn 13.18 13.18 13.02 12.87 12.56 12.4 12.25 12.09 11.94 11.78 11.63 11.47 11.32 11.32 11.32 11.47 11.63 12.09 12.4 12.71 13.18 13.48 13.79 13.94 13.94 13.94 13.79 13.64 13.48 13.18 13.02 12.87 12.56

Dixie up 13.42 13.26 12.95 12.79 12.64 12.33 12.02 11.86 11.71 11.55 11.39 11.39 11.24 11.24 11.24 11.39 11.71 12.02 12.33 12.79 13.26 13.72 14.19 14.5 14.5 14.5 14.34 14.19 13.88 13.72 13.42 13.11 12.95

Dixie dn 13.46 13.3 12.99 12.84 12.53 12.22 12.06 11.75 11.59 11.44 11.44 11.28 11.28 11.28 11.28 11.59 11.75 12.22 12.53 12.99 13.61 14.07 14.38 14.54 14.69 14.54 14.38 14.23 13.92 13.61 13.46 13.15 12.99

Mason up 12.63 12.32 12.17 11.86 11.71 11.39 11.24 11.08 10.93 10.78 10.62 10.47 10.31 10.31 10.31 10.47 10.93 11.24 11.71 12.32 12.79 13.41 13.72 14.02 14.02 13.87 13.56 13.25 12.94 12.63 12.32 12.17 11.86

275

Mason dn 11.31 11.15 10.84 10.69 10.53 10.53 10.38 10.38 10.38 10.53 10.99 11.46 11.92 12.39 13.01 13.47 13.78 13.93 13.93 13.78 13.47 13.17 12.86 12.54 12.23 12.08 11.77 11.61 11.46 11.15 10.99 10.84 10.84

February 2009 Conway up 13.09 12.94 12.63 12.47 12.32 12.16 12.01 11.86 11.7 11.54 11.54 11.39 11.24 11.24 11.39 11.54 11.86 12.01 12.63 12.94 13.4 13.86 14.32 14.48 14.48 14.17 13.86 13.56 13.24 12.94 12.63 12.47 12.32

Conway dn 13.06 12.91 12.75 12.44 12.28 12.28 12.13 11.82 11.66 11.51 11.51 11.51 11.35 11.35 11.35 11.51 11.66 11.97 12.44 12.91 13.22 13.68 14.14 14.46 14.46 14.3 13.99 13.68 13.22 12.91 12.75 12.44 12.28

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/12/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004

Time 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52

Notus dn 12.53 12.37 12.22 12.07 11.91 12.07 12.22 12.53 12.84 13.31 13.31 13.31 13.62 13.93 13.93 13.77 13.62 13.46 13.31 13.15 13.15 12.99 12.84 12.68 12.53 12.22 11.91 11.76 11.6 11.91 12.22 12.68 13.31

Notus up 12.59 12.44 12.28 12.13 11.97 11.97 12.13 12.28 12.75 13.06 13.22 13.06 13.37 13.68 13.83 13.68 13.52 13.37 13.37 13.22 13.06 13.06 12.91 12.75 12.44 12.28 11.97 11.82 11.66 11.66 11.97 12.44 13.06

Indian up 12.41 12.25 12.09 11.94 11.78 11.78 11.94 12.09 12.41 12.88 13.19 13.34 13.81 14.27 14.43 14.59 14.43 14.27 13.96 13.81 13.5 13.19 12.88 12.57 12.25 11.94 11.63 11.47 11.32 11.32 11.63 12.09 12.57

Indian dn 12.4 12.25 12.09 11.94 11.94 11.94 11.94 12.25 12.56 12.87 13.18 13.48 13.79 14.26 14.41 14.41 14.41 14.26 13.94 13.79 13.48 13.18 12.87 12.56 12.25 11.94 11.63 11.47 11.32 11.47 11.63 12.09 12.71

Dixie up 12.79 12.48 12.33 12.17 12.02 12.02 12.02 12.33 12.64 12.95 13.72 13.88 14.34 14.97 15.13 15.29 15.29 14.97 14.66 14.34 14.03 13.57 13.11 12.79 12.33 12.02 11.71 11.39 11.24 11.24 11.39 12.02 12.64

Dixie dn 12.68 12.53 12.37 12.22 12.06 12.06 12.06 12.53 12.84 13.15 13.92 14.07 14.69 15.17 15.33 15.49 15.33 15.01 14.69 14.38 13.92 13.46 13.15 12.68 12.37 12.06 11.75 11.44 11.28 11.28 11.59 12.22 12.99

Mason up 11.55 11.39 11.08 10.93 10.93 10.78 10.93 11.24 11.71 12.32 12.94 13.41 13.72 14.33 14.49 14.65 14.49 14.18 13.87 13.41 12.94 12.48 12.02 11.55 11.24 10.78 10.47 10.16 10 10.16 10.47 11.08 12.17

276

Mason dn 10.99 11.31 11.77 12.39 13.01 13.47 13.93 14.4 14.56 14.56 14.4 14.09 13.78 13.32 12.86 12.39 11.92 11.46 11.15 10.84 10.38 10.22 10.07 10.22 10.53 11.15 12.08 13.17 14.24 15.19 15.82 16.46 16.62

February 2009 Conway up 12.16 11.86 11.86 11.7 11.54 11.54 11.7 12.01 12.47 13.09 13.71 13.86 14.01 14.48 14.95 14.63 14.32 14.17 13.86 13.56 13.09 12.63 12.32 11.86 11.54 11.24 10.93 10.77 10.47 10.62 10.93 11.7 12.47

Conway dn 12.13 11.97 11.82 11.66 11.51 11.51 11.66 11.97 12.44 12.91 13.53 13.83 13.83 14.3 14.93 14.77 14.46 14.14 13.83 13.53 13.22 12.75 12.28 11.97 11.66 11.35 11.04 10.73 10.58 10.58 10.89 11.51 12.28

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/13/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/15/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004

Time 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52

Notus dn 13.93 14.39 14.87 15.34 15.5 15.5 15.5 15.34 15.34 15.18 15.18 14.56 14.71 14.71 14.71 14.56 14.56 14.71 14.71 14.56 14.56 14.56 14.39 14.24 14.08 14.08 13.93 13.62 13.46 13.31 12.99 12.84 12.84

Notus up 13.68 14.14 14.77 15.08 15.41 15.41 15.41 15.24 15.24 15.08 15.08 14.45 14.61 14.61 14.61 14.45 14.45 14.45 14.61 14.45 14.45 14.45 14.29 14.29 14.14 13.98 13.83 13.68 13.37 13.22 13.06 12.91 12.75

Indian up 13.34 13.96 14.74 15.39 15.87 16.02 16.18 16.02 15.87 15.54 15.39 16.18 15.71 15.39 14.91 14.59 14.12 13.81 13.5 13.34 13.34 13.5 13.66 13.81 14.12 14.27 14.59 14.74 14.91 14.91 14.91 14.91 14.74

Indian dn 13.33 14.1 14.73 15.36 15.83 15.99 15.99 15.99 15.83 15.52 15.36 16.15 15.68 15.36 14.88 14.57 14.26 13.79 13.64 13.48 13.33 13.48 13.64 13.94 14.1 14.26 14.57 14.73 14.88 14.88 14.88 14.88 14.73

Dixie up 13.57 14.5 15.61 16.4 17.04 17.52 17.68 17.52 17.36 16.88 16.56 17.2 16.72 16.24 15.77 15.29 14.82 14.5 14.19 13.88 13.88 13.88 14.19 14.5 14.82 15.13 15.29 15.45 15.61 15.61 15.61 15.45 15.29

Dixie dn 13.92 14.86 15.96 16.75 17.39 17.87 17.87 17.71 17.39 16.91 16.43 17.23 16.75 16.12 15.64 15.17 14.69 14.38 14.07 13.92 13.92 14.07 14.23 14.69 14.86 15.33 15.49 15.64 15.64 15.81 15.64 15.49 15.33

Mason up 13.25 14.18 15.12 15.92 16.39 16.7 16.7 16.39 16.07 15.6 15.28 15.76 15.28 14.65 14.18 13.72 13.1 12.79 12.32 12.17 12.17 12.48 12.79 13.25 13.56 13.87 14.18 14.33 14.49 14.65 14.65 14.49 14.33

277

Mason dn 16.62 16.46 16.14 15.66 15.19 14.71 14.24 13.93 13.47 13.01 12.7 12.7 12.39 12.23 12.23 12.54 12.86 13.32 13.78 14.09 14.24 14.4 14.56 14.71 14.71 14.56 14.4 14.24 14.09 13.78 13.63 13.32 13.01

February 2009 Conway up 13.4 14.32 15.27 16.22 16.85 17.01 16.85 16.53 16.22 15.74 15.27 15.58 14.95 14.32 13.86 13.24 12.78 12.47 12.01 11.86 11.86 12.16 12.47 12.94 13.24 13.56 13.86 14.01 14.32 14.48 14.63 14.63 14.48

Conway dn 13.06 13.99 14.93 15.88 16.52 16.99 16.83 16.52 16.2 15.88 15.41 15.73 15.09 14.46 13.99 13.37 12.91 12.59 12.13 11.97 11.82 12.13 12.44 12.75 13.22 13.53 13.68 13.99 14.14 14.46 14.62 14.62 14.62

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/16/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004

Time 9:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52

Notus dn 12.99 13.31 13.62 14.24 14.71 15.18 15.5 15.66 15.98 15.98 15.98 15.98 15.82 15.66 15.66 15.5 15.34 15.18 14.87 14.71 14.39 14.08 13.77 13.77 13.77 13.93 14.39 15.03 15.34 15.66 15.5 15.66 15.66

Notus up 12.91 13.06 13.52 13.83 14.45 14.92 15.24 15.41 15.72 15.88 15.88 15.88 15.72 15.72 15.56 15.41 15.24 15.08 14.92 14.61 14.45 14.14 13.83 13.68 13.68 13.83 14.14 14.77 15.08 15.41 15.41 15.56 15.56

Indian up 14.59 14.43 14.27 14.12 13.81 13.66 13.34 13.19 13.03 12.88 12.72 12.72 12.88 13.34 13.81 14.27 14.91 15.54 16.02 16.5 16.66 16.66 16.66 16.5 16.18 15.87 15.54 15.23 14.91 14.43 14.12 13.81 13.5

Indian dn 14.57 14.41 14.26 14.1 13.79 13.64 13.48 13.18 13.02 12.87 12.71 12.71 13.02 13.33 13.79 14.41 15.04 15.52 15.99 16.47 16.62 16.62 16.62 16.47 16.15 15.99 15.68 15.2 14.88 14.57 14.1 13.79 13.48

Dixie up 15.13 14.97 14.66 14.5 14.19 13.88 13.57 13.26 13.11 12.79 12.64 12.64 12.95 13.26 13.88 14.5 15.45 16.24 16.88 17.36 17.84 18 17.84 17.68 17.36 16.88 16.4 15.92 15.45 14.97 14.66 14.34 14.03

Dixie dn 15.17 15.01 14.69 14.38 14.23 13.92 13.61 13.3 12.99 12.84 12.68 12.84 13.15 13.61 14.23 14.86 15.81 16.59 17.23 17.87 18.19 18.19 18.03 17.71 17.39 16.91 16.28 15.81 15.49 15.01 14.69 14.23 13.92

Mason up 14.18 14.02 13.87 13.56 13.25 13.1 12.79 12.48 12.17 11.86 11.71 11.71 12.02 12.48 13.1 14.02 14.81 15.76 16.23 16.7 17.02 17.02 16.86 16.54 16.07 15.6 15.28 14.81 14.33 13.87 13.41 13.1 12.63

278

Mason dn 12.7 12.39 12.08 11.92 11.77 11.77 12.08 12.7 13.32 14.24 15.19 15.98 16.46 16.77 17.09 17.09 16.93 16.62 16.14 15.66 15.19 14.71 14.24 13.78 13.47 13.01 12.7 12.39 12.23 12.23 12.54 13.17 13.93

February 2009 Conway up 14.32 14.01 13.86 13.56 13.24 13.09 12.78 12.47 12.16 11.86 11.7 11.86 12.16 12.78 13.4 14.01 14.79 15.42 16.22 16.53 17.33 17.33 17.17 16.69 16.22 15.58 14.95 14.32 13.86 13.4 13.09 12.78 12.32

Conway dn 14.3 14.14 13.83 13.53 13.37 13.06 12.91 12.59 12.28 11.97 11.82 11.82 12.13 12.59 13.22 13.83 14.62 15.09 15.88 16.36 17.15 17.31 17.15 16.83 16.36 15.73 15.09 14.46 13.99 13.53 13.06 12.75 12.44

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/17/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/18/2004 5/19/2004 5/19/2004 5/19/2004

Time 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52

Notus dn 15.5 15.5 15.5 15.34 15.34 15.18 15.03 15.03 14.87 14.71 14.56 14.39 14.24 14.08 13.93 13.93 13.93 13.77 14.24 14.71 15.03 15.34 15.5 15.34 15.18 15.18 15.03 15.03 14.87 14.87 14.71 14.56 14.39

Notus up 15.56 15.41 15.41 15.41 15.24 15.08 15.08 14.92 14.92 14.77 14.61 14.45 14.29 13.98 13.83 13.83 13.83 13.83 13.83 14.45 14.92 15.08 15.56 15.24 15.24 15.08 15.08 14.92 14.92 14.77 14.61 14.61 14.45

Indian up 13.34 13.19 13.19 13.34 13.66 14.27 14.74 15.23 15.54 15.87 16.02 16.18 16.18 16.02 15.87 15.54 15.39 15.23 14.91 14.59 14.43 14.12 13.96 13.81 13.81 13.66 13.66 13.66 13.66 13.96 14.59 14.43 14.12

Indian dn 13.33 13.18 13.18 13.48 13.79 14.41 14.88 15.2 15.52 15.83 15.99 16.15 16.15 15.99 15.83 15.68 15.36 15.04 14.88 14.57 14.41 14.26 14.1 13.79 13.79 13.64 13.64 13.64 13.64 14.1 14.57 14.41 14.26

Dixie up 13.72 13.57 13.57 13.57 13.88 14.5 15.29 15.92 16.4 16.56 17.04 17.04 16.88 16.56 16.24 15.92 15.61 15.29 15.13 14.82 14.66 14.5 14.5 14.34 14.19 14.03 14.03 14.03 14.19 14.03 15.29 15.13 14.82

Dixie dn 13.76 13.46 13.46 13.76 14.07 14.69 15.64 16.28 16.59 16.91 17.23 17.07 16.91 16.59 16.28 15.96 15.64 15.33 15.17 14.86 14.69 14.54 14.38 14.23 14.23 14.07 14.07 14.07 14.23 14.07 15.33 15.17 14.86

Mason up 12.32 12.17 12.17 12.48 12.94 13.56 14.33 15.12 15.44 15.76 15.92 16.07 16.07 15.92 15.6 15.28 14.96 14.65 14.33 14.02 13.72 13.56 13.41 13.1 12.94 12.94 12.79 12.94 12.94 13.25 14.18 13.87 13.72

279

Mason dn 14.71 15.34 15.66 15.98 16.14 16.29 16.14 15.82 15.66 15.34 14.87 14.56 14.24 14.09 13.78 13.47 13.32 13.17 13.01 12.86 12.86 13.01 13.01 13.47 14.09 14.71 15.34 15.51 15.66 15.51 12.54 12.39 12.39

February 2009 Conway up 12.16 11.86 11.86 12.32 12.94 13.71 14.48 15.27 15.9 16.06 16.22 16.37 16.22 15.9 15.42 14.95 14.63 14.32 14.01 13.71 13.56 13.4 13.24 13.09 13.09 12.94 12.94 13.09 13.4 13.4 14.63 14.32 14.17

Conway dn 12.13 11.82 11.82 12.28 12.75 13.53 14.14 15.09 15.73 16.04 16.04 16.36 16.36 15.88 15.57 15.09 14.77 14.3 13.99 13.68 13.53 13.37 13.22 13.22 13.06 12.91 12.91 13.06 13.37 13.37 14.62 14.46 14.14

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 5/19/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/27/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004

Time 3:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52

Notus dn 14.24 15.34 15.18 15.03 15.18 15.18 15.5 15.66 16.14 16.29 16.14 16.14 15.98 15.98 16.14 16.14 16.14 16.14 15.98 15.82 15.66 15.66 15.5 15.5 15.34 15.03 14.87 14.71 14.56 14.39 14.39 14.56 14.71

Notus up 14.29 15.41 15.24 15.08 14.92 15.08 15.24 15.56 16.04 16.19 16.04 16.04 15.88 15.88 15.88 16.04 16.04 16.04 15.88 15.88 15.72 15.56 15.41 15.41 15.24 15.08 14.92 14.61 14.61 14.45 14.29 14.45 14.45

Indian up 15.39 15.23 14.91 14.74 14.74 14.91 15.07 15.23 15.54 15.87 16.02 16.18 16.18 16.34 16.34 16.18 16.18 16.02 15.87 15.87 15.71 15.39 15.23 15.07 14.91 14.74 14.74 14.59 14.43 14.43 14.27 14.43 14.59

Indian dn 15.36 15.2 15.04 14.88 14.73 14.88 15.04 15.2 15.68 15.68 15.99 15.99 16.15 16.31 16.31 16.31 16.15 15.99 15.99 15.68 15.68 15.52 15.2 15.04 14.88 14.88 14.73 14.57 14.41 14.41 14.26 14.41 14.57

Dixie up 15.77 15.77 15.61 15.45 15.61 15.77 16.08 16.56 17.2 17.2 17.2 17.2 17.04 17.04 17.2 17.2 17.04 16.72 16.56 16.4 16.24 16.08 15.92 15.77 15.61 15.45 15.29 15.13 14.97 14.97 14.97 15.13 15.29

Dixie dn 16.12 15.81 15.49 15.49 15.64 15.81 16.28 16.75 17.23 17.23 17.23 17.23 17.23 17.23 17.39 17.23 17.07 16.75 16.59 16.43 16.28 16.12 15.96 15.81 15.64 15.49 15.33 15.17 15.01 15.01 15.01 15.17 15.49

Mason up 15.44 14.65 14.33 14.18 14.18 14.18 14.33 14.49 15.12 15.76 15.92 16.07 16.07 16.07 16.07 16.07 15.92 15.92 15.6 15.44 15.12 14.96 14.65 14.49 14.33 14.33 14.18 14.02 13.87 13.72 13.72 13.72 13.87

280

Mason dn 14.56 14.71 15.34 15.82 15.98 16.14 16.14 16.14 16.14 16.14 15.98 15.82 15.66 15.51 15.19 15.03 14.87 14.71 14.56 14.4 14.24 14.09 13.93 13.78 13.78 13.93 13.93 14.24 14.87 14.87 15.34 15.66 15.82

February 2009 Conway up 15.42 14.17 14.01 13.86 14.01 14.17 14.48 14.95 15.58 15.9 15.9 15.9 15.9 15.9 15.74 15.74 15.58 15.42 15.11 14.95 14.79 14.63 14.48 14.32 14.32 14.17 14.01 13.86 13.86 13.86 13.71 14.01 14.32

Conway dn 15.41 14.14 13.99 13.83 13.99 14.14 14.46 14.77 15.25 15.73 15.88 15.88 15.88 15.88 15.73 15.73 15.57 15.25 15.09 14.93 14.77 14.62 14.46 14.3 14.3 14.14 13.99 13.99 13.83 13.83 13.68 13.83 13.99

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/28/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 5/29/2004 6/29/2004 6/29/2004 6/29/2004 6/29/2004 6/29/2004 6/29/2004 6/29/2004 6/29/2004 6/29/2004 6/29/2004

Time 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52

Notus dn 15.18 15.34 15.18 15.5 15.5 15.5 15.34 15.34 15.18 15.03 14.87 14.71 14.39 14.24 13.93 13.62 13.46 13.15 12.99 12.99 13.15 13.31 13.46 19.68 20.17 20.65 21.31 21.81 22.31 22.31 21.64 21.14 20.82

Notus up 14.92 15.24 15.24 15.41 15.41 15.41 15.41 15.24 15.08 14.92 14.92 14.61 14.45 14.29 13.98 13.68 13.37 13.22 12.91 12.91 13.06 13.22 13.37 19.57 20.06 20.38 21.03 21.7 22.2 22.37 21.87 21.2 20.87

Indian up 14.91 15.23 15.07 15.71 15.87 16.02 15.87 15.71 15.54 15.23 14.91 14.59 14.43 14.12 13.81 13.66 13.34 13.03 12.88 12.88 12.88 13.03 13.34 18.43 18.76 19.08 19.74 20.23 20.88 21.05 20.88 20.72 20.56

Indian dn 14.88 15.2 15.04 15.68 15.83 15.99 15.83 15.68 15.52 15.2 15.04 14.73 14.41 14.1 13.94 13.64 13.48 13.18 13.02 12.87 12.87 13.18 13.33 18.38 18.7 19.19 19.68 20.32 20.81 20.97 20.81 20.64 20.48

Dixie up 16.08 16.24 16.24 16.56 16.72 16.56 16.4 16.24 15.92 15.77 15.45 15.13 14.82 14.5 14.19 13.88 13.57 13.26 13.11 12.95 13.26 13.57 14.03 20.42 20.75 21.25 21.92 22.59 23.09 23.09 22.59 22.26 22.09

Dixie dn 16.28 16.43 16.43 16.75 16.75 16.59 16.43 16.28 15.96 15.64 15.33 15.17 14.86 14.38 14.07 13.76 13.61 13.3 13.15 12.99 13.3 13.61 14.23 20.62 20.95 21.62 22.28 22.78 23.29 23.12 22.62 22.28 22.28

Mason up 14.18 14.81 14.96 15.28 15.92 16.07 16.07 15.76 15.44 15.12 14.65 14.33 14.02 13.56 13.25 12.94 12.48 12.17 12.02 11.86 11.86 12.02 12.48 17.98 18.46 19.11 19.92 20.57 21.39 21.72 21.39 20.89 20.41

281

Mason dn 15.98 15.82 15.51 15.03 14.71 14.4 14.09 13.63 13.32 13.01 12.7 12.39 12.08 11.92 11.92 12.23 12.54 13.01 13.63 14.24 14.87 15.51 15.98 21.8 21.47 20.97 20.47 19.99 19.67 19.34 19.02 18.69 18.37

February 2009 Conway up 14.79 15.42 15.74 16.06 16.22 16.06 15.74 15.27 14.95 14.63 14.17 13.71 13.24 12.78 12.47 12.16 11.86 11.7 11.54 11.7 12.01 12.47 13.09 18.77 19.09 19.74 20.39 21.04 21.54 21.71 21.04 20.23 19.91

Conway dn 14.3 14.93 15.25 15.57 15.73 15.88 15.57 15.41 15.09 14.77 14.3 13.99 13.53 13.22 12.91 12.59 12.28 12.13 11.97 11.82 11.97 12.28 12.75 18.76 18.92 19.74 20.38 20.87 21.54 21.71 21.21 20.38 19.9

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 6/29/2004 6/29/2004 6/29/2004 6/29/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 6/30/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/19/2004 7/20/2004 7/20/2004 7/20/2004

Time 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52

Notus dn 20.65 20.49 20.33 20.01 19.84 19.52 19.19 18.86 18.53 18.21 18.05 17.73 17.73 17.89 18.21 18.7 19.19 20.33 20.82 21.48 22.14 22.48 22.99 22.99 22.48 22.31 21.98 21.81 21.48 21.31 21.14 21.14 20.82

Notus up 20.71 20.38 20.22 20.06 19.73 19.41 19.24 18.92 18.59 18.27 17.95 17.79 17.63 17.63 17.95 18.43 18.92 20.06 20.71 21.53 22.03 22.53 22.87 23.04 22.71 22.37 22.03 21.7 21.53 21.37 21.2 21.03 20.87

Indian up 20.23 19.9 19.57 19.24 18.92 18.59 18.27 17.94 17.62 17.46 17.14 16.98 16.82 16.98 17.14 17.46 17.94 19.08 19.41 20.06 20.39 20.88 21.38 21.71 21.54 21.71 21.54 21.38 21.21 21.05 20.72 20.56 20.39

Indian dn 20.16 19.84 19.51 19.19 18.86 18.54 18.22 17.89 17.73 17.42 17.1 16.94 16.94 16.94 17.1 17.57 18.06 18.86 19.03 19.35 19.68 20 20.32 20.64 20.81 20.97 21.14 21.3 21.14 21.14 20.97 20.81 20.64

Dixie up 21.92 21.59 21.08 20.75 20.42 20.1 19.78 19.46 19.13 18.81 18.64 18.32 18.32 18.48 18.64 19.13 19.78 20.59 21.08 21.76 22.26 22.92 23.43 23.77 23.6 23.6 23.43 23.09 22.76 22.42 22.26 21.92 21.59

Dixie dn 21.95 21.45 21.12 20.78 20.46 20.13 19.81 19.49 19.17 18.84 18.52 18.36 18.36 18.52 18.84 19.33 19.97 20.78 21.28 21.95 22.62 23.29 23.63 23.97 23.8 23.63 23.46 23.12 22.78 22.45 22.12 21.95 21.62

Mason up 19.92 19.6 19.27 18.95 18.62 18.3 17.98 17.66 17.18 16.86 16.54 16.23 16.07 16.23 16.39 16.86 17.49 18.62 19.11 19.76 20.41 21.06 21.72 21.89 22.06 21.89 21.72 21.56 21.22 21.06 20.89 20.57 20.41

282

Mason dn 18.05 17.73 17.41 16.93 16.62 16.46 16.29 16.29 16.62 17.09 17.73 18.37 19.18 19.83 20.31 20.64 20.64 22.13 22.13 22.13 21.97 21.63 21.3 21.13 20.97 20.64 20.47 20.15 19.83 19.67 19.34 19.18 19.02

February 2009 Conway up 19.58 19.42 19.26 18.77 18.44 17.97 17.81 17.49 17.17 17.01 16.85 16.69 16.69 17.01 17.49 17.81 18.29

Conway dn 19.74 19.58 19.25 18.92 18.43 17.95 17.79 17.47 17.31 16.99 16.83 16.68 16.68 16.99 17.31 17.79 18.27

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 7/20/2004 7/20/2004 7/20/2004 7/20/2004 7/20/2004 7/20/2004 7/20/2004 7/20/2004 7/20/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/16/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004

Time 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52 11:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52 2:52 3:52 4:52 5:52 6:52 7:52 8:52 9:52 10:52

Notus dn 20.65 20.49 20.17 20.01 19.84 19.84 20.01 20.33 20.65 20.11 20.11 20.27 20.43 20.76 20.92 21.08 21.08 21.25 21.25 21.25 21.08 21.08 20.92 20.76 20.59 20.59 20.43 20.43 20.27 20.11 20.11 19.94 19.94

Notus up 20.71 20.38 20.22 19.89 19.73 19.73 19.89 20.22 20.54 20.74 21.23 21.56 21.89 22.22 22.39 22.39 22.39 22.39 22.22 22.06 21.89 21.56 21.39 21.23 21.07 20.91 20.74 20.58 20.42 20.26 20.09 20.09 20.09

Indian up 20.06 19.9 19.57 19.41 19.24 19.24 19.24 19.41 19.74 20.06 20.38 20.54 20.71 20.88 21.04 21.38 21.38 21.21 21.04 20.88 20.71 20.54 20.54 20.38 20.38 20.22 20.06 19.89 19.73 19.57 19.41 19.41 19.41

Indian dn 20.48 20.32 20.16 19.84 19.68 19.51 19.51 19.51 19.51 20.16 20.32 20.48 20.81 20.97 21.14 21.3 21.3 21.3 21.14 20.97 20.81 20.64 20.64 20.48 20.32 20.16 20 19.84 19.68 19.51 19.51 19.51 19.51

Dixie up 21.42 21.08 20.92 20.59 20.42 20.42 20.42 20.59 20.75 21.25 21.42 21.76 22.26 22.59 22.76 22.76 22.76 22.76 22.59 22.42 22.26 22.09 21.92 21.59 21.42 21.25 21.08 20.92 20.75 20.59 20.59 20.42 20.59

Dixie dn 21.28 21.12 20.78 20.62 20.46 20.46 20.46 20.62 20.95 21 21.17 21.5 22 22.33 22.5 22.67 22.67 22.67 22.67 22.33 22.17 22 21.83 21.67 21.5 21.33 21 20.83 20.67 20.67 20.51 20.34 20.34

Mason up 20.08 19.76 19.6 19.27 19.11 18.78 18.78 18.95 19.27 19.86 20.02 20.34 20.5 20.83 20.99 20.99 20.99 20.99 20.83 20.83 20.67 20.5 20.5 20.34 20.18 20.02 19.86 19.69 19.37 19.21 19.21 19.04 19.04

283

Mason dn 18.86 19.02 19.34 19.67 20.31 20.8 21.47 21.8 22.13 20.15 19.99 19.83 19.67 19.67 19.67 19.83 19.99 20.15 20.47 20.64 20.8 20.97 21.13 21.13 20.97 20.97 20.8 20.64 20.47 20.47 20.31 20.15 19.99

February 2009 Conway up

Conway dn

19.02 19.18 19.67 20.16 20.48 20.64 20.64 20.64 20.64 20.32 19.99 19.67 19.5 19.5 19.34 19.18 19.02 18.85 18.69 18.53 18.37 18.37 18.37

18.76 19.42 19.9 20.54 20.71 21.04 21.04 20.87 20.71 20.54 20.22 20.06 19.58 19.25 18.92 18.43 18.11 17.79 17.47 17.31 17.15 17.15 17.63

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Day 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/17/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/22/2004 8/23/2004 8/23/2004

Time 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 6:52 7:52 8:52 9:52 10:52 11:52 12:52 13:52 14:52 15:52 16:52 17:52 18:52 19:52 20:52 21:52 22:52 23:52 0:52 1:52

Notus dn 19.78 19.78 19.78 19.94 20.11 20.43 20.59 20.76 20.92 20.92 20.92 20.76 20.59 20.27 20.11 19.94 19.78 19.78 19.78 19.62 19.62 19.62 19.62 19.62 19.62 19.62 19.45 19.45 19.29 19.13 19.13 18.97 18.8

Notus up 20.09 20.09 20.42 20.74 21.23 21.56 22.06 22.06 21.89 21.72 21.56 21.23 21.07 20.26 19.93 19.93 19.77 19.77 19.77 19.93 20.09 20.09 19.93 19.93 19.77 19.6 19.44 19.12 18.95 18.79 18.63 18.47 18.31

Indian up 19.41 19.41 19.73 20.06 20.38 20.54 20.71 20.71 20.71 20.71 20.54 20.38 20.22 19.41 19.08 18.92 18.92 18.76 18.76 18.92 18.92 19.08 19.08 18.92 18.92 18.76 18.59 18.43 18.43 18.11 18.11 17.94 17.78

Indian dn 19.35 19.51 19.84 20 20.32 20.64 20.81 20.81 20.81 20.64 20.48 20.32 20.32 19.35 19.19 19.03 18.86 18.86 18.86 18.86 19.03 19.03 19.03 19.03 18.86 18.86 18.7 18.54 18.38 18.22 18.06 17.89 17.73

Dixie up 20.59 20.75 20.92 21.25 21.59 21.92 22.09 22.26 22.09 22.09 22.09 21.92 21.76 20.1 19.94 19.78 19.78 19.78 19.78 19.78 19.94 19.78 19.78 19.78 19.62 19.62 19.29 19.13 18.97 18.81 18.64 18.48 18.32

Dixie dn 20.51 20.51 20.67 21 21.33 21.67 21.83 22 22 22 22 21.83 21.67 20.18 20.02 19.86 19.7 19.7 19.7 19.7 19.7 19.7 19.7 19.7 19.54 19.54 19.37 19.21 19.05 18.89 18.72 18.56 18.4

Mason up 18.88 19.04 19.21 19.53 20.02 20.34 20.5 20.5 20.5 20.34 20.18 20.02 20.02 18.72 18.55 18.39 18.39 18.39 18.39 18.39 18.55 18.55 18.55 18.55 18.39 18.23 18.07 17.91 17.74 17.58 17.43 17.43 17.27

284

Mason dn 19.83 19.67 19.51 19.34 19.18 19.18 19.02 19.02 19.18 19.34 19.67 19.99 20.15 20.15 19.99 19.83 19.67 19.51 19.34 19.02 18.86 18.69 18.53 18.53 18.53 18.53 18.53 18.69 18.69 18.69 18.53 18.37 18.21

February 2009 Conway up 18.37 18.37 18.69 19.18 19.67 20.16 20.48 20.64 20.64 20.48 20.32 20.16 19.99 17.72 17.56 17.4 17.4 17.56 17.56 17.72 17.72 17.72 17.72 17.56 17.56 17.4 17.24 17.24 16.92 16.92 16.77 16.61 16.45

Conway dn 18.27 18.92 19.58 20.38 20.87 21.37 21.54 21.37 21.04 20.87 20.38 20.06 19.58 17.53 17.53 17.69 18.33 18.82 19.14 19.63 20.28 20.93 21.26 21.43 21.26 21.1 20.61 20.12 19.79 19.31 18.98 18.66 18.49

Lower Boise River 5-year Subbasin Assessment and TMDL Review Notus Notus Indian Indian Dixie dn up up dn up Day Time 8/23/2004 2:52 18.8 18.14 17.62 17.57 18.16 8/23/2004 3:52 18.64 17.98 17.46 17.42 18 8/23/2004 4:52 18.48 17.82 17.3 17.26 17.68 8/23/2004 5:52 18.32 17.66 17.14 17.1 17.52 8/23/2004 6:52 18.16 17.5 16.98 16.94 17.36 8/23/2004 7:52 18.16 17.34 16.82 16.94 17.2 8/23/2004 8:52 17.99 17.18 16.66 16.78 17.2 8/23/2004 9:52 17.83 17.18 16.66 16.78 17.2 8/23/2004 10:52 17.83 17.34 16.82 16.78 17.36 8/23/2004 11:52 17.83 17.66 16.98 17.1 17.68 Dn = downstream; up = upstream of locations listed in Table C-11.

Dixie dn 18.08 17.92 17.76 17.59 17.43 17.28 17.12 17.12 17.12 17.43

Mason up 17.11 16.95 16.63 16.47 16.47 16.32 16.16 16.32 16.47 16.63

285

Mason dn 18.05 17.89 17.73 17.57 17.57 17.41 17.25 17.09 16.93 16.77

February 2009 Conway up 16.45 16.13 15.97 15.82 15.82 15.82 15.66 15.82 15.97 16.45

Conway dn 18.17 17.85 17.53 17.21 17.06 16.89 17.21 17.69 18.17 18.66

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Lower Boise River Drains and Tributary Ammonia Data, 2008 0.25

Ammonia (mg/L)

0.20

0.15

0.10

0.05

11 /1 7/ 20 08

10 /8 /2 00 8

8/ 29 /2 00 8

7/ 20 /2 00 8

6/ 10 /2 00 8

5/ 1/ 20 08

0.00

Date Thurman Drain Sand Hollow, Oasis

E. Hartley Sand Hollow, Market

W. Hartley Indian Creek-Kings RD

Figure C-1. Reported results of ammonia from samples collected from the Lower Boise River Drains and Tributaries by DEQ, 2008.

286

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Dissolved Oxygen Concentration Lower Boise River Subbasin, 2008 (selected locations) 12

Dissloved Oxygen (mg/L)

11 10 9 8 7 6 5 4 08 /20 1 / 5

0 0/2 6/1

08

0 0/2 7/2

08

0 9/2 8/2

08

20 /8/ 10

08

/2 /17 11

8 00

Date Thurman Drain Indian Creek-Kings RD

W. Hartley Drain Minimum Criteria

E. Hartley Drain

Figure C-2. Reported results of dissolved oxygen (DO) from data collected from Lower Boise River load allocation locations by DEQ, 2008. Dissolved Oxygen Concentration, AU 017, Sand Hollow Creek, 2008 11

Dissloved Oxygen (mg/L)

10 9 8 7 6 5 4 3 2 08 / 20 5/ 1

8 00 0/2 1 / 6

8 00 0/2 2 / 7

8 00 9/2 2 / 8

08 20 /8/ 0 1

/2 /17 11

8 00

Date Sand Hollow at Oasis RD

Sand Hollow near Market RD

Minimum Criteria

Figure C-3. Reported results of dissolved oxygen (DO) from data collected from Sand Hollow Creek (AU 017) by DEQ, 2008. 287

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Water Temperature Data from Lower Boise River Subbasin, 2008 (selected locations)

Water Temperature (*C)

29 26 23 20 17 14 11 8 08 / 20 5/1

0 0/2 6/ 1

08

0 0/ 2 7/2

08

0 9/2 8/ 2

08

0 8/2 10 /

08

2 17 / 11 /

008

Date Thurman Drain Indian Creek near Kings RD

E. Hartley Drain SS Daily Maximum Criteria

W. Hartley Drain

Figure C-4. Reported results of water temperature from data collected from Lower Boise River load allocation locations by DEQ, 2008. Water Temperature Data, AU 017, Sand Hollow Creek, 2008 28 Water Temperature (*C)

26 24 22 20 18 16 14 12 10 8 08 / 20 5/1

0 0/ 2 6/ 1

08

0 0/2 7/2

08

0 9/ 2 8/ 2

08

0 8/2 10 /

08

2 17 / 11 /

008

Date Sand Hollow at Oasis RD MOD* Daily Maximum Criteria

Sand Hollow near Market RD

Figure C-5. Reported results of water temperature from data collected from Sand Hollow Creek (AU 017) by DEQ, 2008.

288

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

E. coli Data from Lower Boise River Subbasin, 2008 (selected locations) 1200

E. coli (cfu/100ml)

1000 800 600 400 200 0 08 / 20 5/1

0 0/2 6/1

08

0 0/2 7/2

08

0 9/2 8/2

08

0 8/2 10 /

08

2 17 / 11 /

008

Date Thurman Drain Indian Creek-Kings RD Maximum Criteria

W. Hartley Drain Sand Hollow at Oasis RD

E. Hartley Drain Sand Hollow near Market RD

Figure C-6. Reported results of E. coli from data collected from Lower Boise River load allocation locations by DEQ, 2008. Suspended Sediment Data from Lower Boise River Subbasin, 2008 (selected locations)

Suspended Sediment (mg/L)

10000

1000

100

10

1 08 /20 5/1

0 08 0/2 6/ 1

0 08 0/2 7/ 2

0 08 9/ 2 8/2

0 08 8/2 10 /

2 17 / 11 /

008

Date Thurman Drain Indian Creek-Kings RD 60 day Maximum Target

E. Hartley Drain Sand Hollow at Oasis RD 14-day Maximum Target

W. Hartley Drain Sand Hollow near Market RD

Figure C-7. Reported results of suspended sediment from data collected from Lower Boise River load allocation locations by DEQ, 2008.

289

Lower Boise River 5-year Subbasin Assessment and TMDL Review

This page intentionally left blank for correct doubled-sided printing.

290

February 2009

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Appendix D. Designated Management Agency Reports of Implementation Activities and Effectiveness

291

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table D-1. Reports of nonpoint source implementation projects in the Lower Boise River subbasin. Received from Idaho Soil Conservation Commission (ISCC) May 29, 2008.

Summary of Actual Best Management Practice (BMP) Expenditures CANYON SCD

HUC: 17050114

Amount Best Management Practice: Installed:

Total BMP Operator State Other Acres ----------Units Counted (E)----------Costs: Funds: Matching: Monies: Treated: Acres Riparian Feet AFO (Head)

Overall Summary of Best Management Practices GRANTS 17050114 PIPELINE – HIGH PRESS.

3235 FT

$25,411

$14,174

$11,237

$0

0

0

0

PIPELINE – LOW PRESS.

40 FT

$4,971

$2,485

$2,485

$0

0

0

0

10391 FT

$68,039

$36,378

$31,661

$0

227

227

0

0

LAND SMOOTHING

15 AC

$9,110

$5,399

$3,711

$0

15

0

0

0

PASTURE & HAYLAND PLANTING

20 AC

$1,622

$811

$811

$0

20

20

0

0

STRUCTURE FOR WATER CONTROL

10 EA

$12,985

$6,492

$6,492

$0

0

0

0

1 EA

$22,580

$12,580

$10,000

$0

100

100

0

1,500

$144,717

$78,320

$66,398

$0

362

347

0

1,500

$66,398

$0

362

347

0

1,500

GATED PIPELINE

WASTE STORAGE FACILITY Project Total:

(A Total of 19 BMPs Recorded)

$144,717

$78,320

E = estimated; AFO = animal feeding operation

292

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Summary of Actual BMP Expenditures CANYON SCD

CONWAY GULCH HUC: 17050114 Total -----Units Counted (E)----Operator State Other Acres Amount BMP Riparian Funds: Matching: Monies: Treated Acres Feet Installed: Costs: Best Management Practice: AFO(Head) CONSERVATION CROP ROTATION

9279 AC

$0

46,395

0

0

0

DEEP TILLAGE

655 AC

$0

655

0

0

0

FILTER STRIP

150 AC

$0

150

0

0

0

29256 FT

$0

0

0

0

PIPELINE – HIGH PRESS.

7574 FT

$0

0

0

0

PIPELINE – LOW PRESS.

59535 FT

$0

0

0

0

1425 AC

$0

14,250

0

0

0

470 AC

$0

470

0

0

0

$0

46,395

9,279

0

0

CONCRETE DITCH

IRRIGATION SYSTEM, SPRINKLER IRRIG. SYSTEM, SURFACE & SUBSURFACE IRRIGATION WATER MANAGEMENT

9279 AC $1,263,085

$607,029

$656,056

LAND SMOOTHING

716 AC

$0

7,160

0

0

0

MULCHING

923 AC

$0

4,615

0

0

0

6565 AC

$0

6,565

0

0

0

RESIDUE MANAGEMENT; MULCH TILL SEDIMENT BASIN

42 EA

$0

0

0

0

STRUCTURE FOR WATER CONTROL

86 EA

$0

0

0

0

2773 FT

$0

0

0

0

9,279

0

0

UNDERGROUND OUTLET Project Total:

$1,263,085 $607,029 $656,056 $0

E = estimated; AFO = animal feeding operation

293

126,655

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Summary of Actual BMP Expenditures CANYON SCD

Dixie Slough WQPA

Best Management Practice: CONSERVATION CROP ROTATION

Amount Installed:

HUC: 17050114 Total BMP Costs:

Operator State Other Funds: Matching: Monies:

----Units Counted (E)--Acres Riparian AFO Treated: Acres Feet (Head)

342.3 AC

$8,535

$8,535

$0

854

70

0

0

2800 FT

$3,444

$861

$2,583

$0

29

29

0

40

0.5 AC

$47

$12

$35

$0

42

0

0

0

13431 FT

$97,250

$25,242

$72,008

$0

290

81

0

0

PIPELINE – CORR. METAL

255 FT

$2,615

$776

$1,839

$0

0

0

0

PIPELINE – HIGH PRESS. UND. PLASTIC

450 FT

$4,706

$1,441

$3,265

$0

0

0

0

PIPELINE – LOW PRESS. UND. PLASTIC

13304 FT

$145,150

$62,130

$83,019

$0

400

26

0

PIPELINE - CONCRETE

1805 FT

$13,523

$3,381

$10,142

$0

0

0

0

PIPELINE – REINF. PLASTIC MORTAR

3860 FT

$33,199

$20,753

$12,446

$0

0

0

0

GATED PIPE

2040 FT

$8,881

$2,220

$6,661

$0

0

0

0

28 FT

$381

$95

$286

$0

0

0

0

IRRIGATION LAND LEVELING

103.4 AC

$58,500

$49,451

$9,049

$0

103

11

0

0

IRRIGATION SYSTEM, SPRINKLER

211.3 AC

$115,124

$58,671

$56,453

$0

211

211

0

0

IRRIGATION WATER MANAGEMENT

342.3 AC

$8,535

$8,535

$0

854

64

0

0

10 AC

$1,500

$1,500

$0

10

0

0

0

342.3 AC

$8,535

$8,535

$0

854

0

0

0

3246 FT

$5,556

$1,389

$4,167

$0

0

0

0

FENCE FILTER STRIP CONCRETE DITCH

PIPELINE - STEEL

LAND SMOOTHING NUTRIENT MANAGEMENT PIPELINE

294

0

Lower Boise River 5-year Subbasin Assessment and TMDL Review

Best Management Practice:

Amount Installed:

PUMPING PLANT FOR WATER CONTROL

Total BMP Costs:

February 2009

Operator State Other Funds: Matching: Monies:

----Units Counted (E)--Acres Riparian AFO Treated: Acres Feet (Head)

2 EA

$14,162

$7,231

$6,932

$0

0

0

0

SEDIMENT BASIN

15 EA

$19,067

$6,267

$12,800

$0

380

219

0

0

STRUCTURE FOR WATER CONTROL

21 EA

$35,430

$20,919

$14,511

$0

102

0

0

0

100 EA

$975

$244

$732

$0

0

0

0

WASTE MANAGEMENT SYSTEM

2 EA

$48,128

$12,032

$36,096

$0

611

611

0

WATER WELL

1 EA

$15,009

$5,009

$10,000

$0

0

0

0

WATERING FACILITY

8 EA

$5,954

$1,488

$4,465

$0

0

0

0

WETLAND RESTORATION

1 EA

$10,282

$3,465

$6,818

$0

29

29

0

0

$664,489

$310,181

$354,309

$0

4,768

1,352

0

240

0

$664,489

$310,181

$354,309

$0

4,768

1,352

0

240

200

TREE/SHRUB ESTABLISHMENT

Project Total: Overall Summary of Best Management Practices (A Total of 75 BMPs Recorded)

E = estimated; AFO = animal feeding operation

295

200

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Summary of Actual BMP Expenditures ADA SWCD

FIFTEENMILE CREEK WQPA

Best Management Practice: ANIONIC POLYACRYLAMIDE (PAM)

HUC: 17050114

Total Amount BMP Installed: Costs: 839 AC

FILTER STRIP

0.6 AC

--Units Counted (E)--Operator State Other Acres Riparian AFO Funds: Matching: Monies: Treated: Acres Feet (Head)

$6,248

$1,621

$4,628

$0

839

100

0

0

$120

$30

$90

$0

1

1

0

0

CONCRETE DITCH-

8176 FT

$56,708

$14,604

$42,104

$0

126

76

0

0

PIPELINE – LOW PRESS. UND. PLASTIC

2891 FT

$19,672

$5,002

$14,670

$0

154

133

0

0

CONCRETE PIPELINE

1925 FT

$14,053

$3,513

$10,539

$0

0

0

0

0

990 FT

$4,693

$1,174

$3,519

$0

0

0

0

0

37885 CY

$52,769

$13,256

$39,513

$0

71

16

0

0

78.3 AC $83,432

$20,998

$62,434

$0

78

78

0

0

$14,450

$3,613

$10,838

$0

29

29

0

0

GATED PIPE IRRIGATION LAND LEVELING IRRIGATION SYSTEM, SPRINKLER IRRIG. SYSTEM, SURFACE & SUBSURFACE

29 AC

NUTRIENT MANAGEMENT

35.7 AC

$176

$44

$132

$0

36

36

0

0

NUTRIENT MANAGEMENT

13 EA

$646

$162

$485

$0

214

20

0

0

PUMPING PLANT FOR WATER CONTROL

2 EA

$17,750

$6,072

$11,678

$0

78

0

0

0

SEDIMENT BASIN

8 EA

$12,552

$3,138

$9,413

$0

81

47

0

0

STRUCTURE FOR WATER CONTROL

1 EA

$935

$298

$638

$0

0

0

0

0

$0

1,708

536

0

0

Project Total:

$284,204 $73,523

$210,680

E = estimated; AFO = animal feeding operation

296

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Table D-2. Summary of nonpoint source implementation projects, 2005 through 2008, in the Lower Boise River subbasin, by Tier. Received from Idaho Soil Conservation Commission (ISCC) January 9, 2009. TMDL 6th Field Subwatershed Target Activity Dixie Slough Irrigation System, Micro irrigation (441) Fifteen Mile Creek Comprehensive Nutrient Management Plan Irrigation Water Conveyance, Ditch and Canal Lining, Plain Concrete Fifteen Mile Creek Irrigation Water Conveyance, Pipeline, LowFifteen Mile Creek Pressure, Underground, Plastic Irrigation Water Conveyance, Pipeline, Rigid Gated Fifteen Mile Creek Pipeline Fifteen Mile Creek Structure for Water Control Fifteen Mile Creek Conservation Crop Rotation Fifteen Mile Creek Nutrient Management Low Line Canal Conservation Crop Rotation Low Line Canal Irrigation System, Surface and Subsurface Irrigation Water Conveyance, Pipeline, Rigid Gated Low Line Canal Pipeline Lower Indian Creek Conservation Crop Rotation Lower Indian Creek Irrigation System, Sprinkler Lower Indian Creek Irrigation Water Management Lower Indian Creek Nutrient Management Lower Indian Creek Pest Management Lower Indian Creek Residue Management, Seasonal Lower Indian Creek Structure for Water Control Lower Indian Creek Surface Roughening Mason Creek Irrigation Water Conveyance, Pipeline, Steel Mason Creek Irrigation Water Management Mason Creek Nutrient Management Mason Creek Residue Management, Seasonal (344) Outlet Boise River Comprehensive Nutrient Management Plan Outlet Boise River Conservation Crop Rotation (328)

297

Tier Number of Receiving Participating Acres Monitoring Treatment Producers Treated Period Tier 1 35.1 Tier 1 21.0 Tier 1

47.0

Tier 1

38.0

Tier 1 Tier 1 Tier 1 Tier 1 Tier 1 Tier 1

29.0 38.0 143.3 167.8 21.9 21.9

Tier 1 Tier 1 Tier 1 Tier 1 Tier 1 Tier 1 Tier 1 Tier 1 Tier 1 Tier 1 Tier 1 Tier 1 Tier 1 Tier 1 Tier 1

72.0 107.7 88.4 107.7 88.4 88.4 19.3 31.2 19.3 88.3 130.5 130.5 130.5 29.8 80.6

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

TMDL 6th Field Subwatershed Target Activity Outlet Boise River Irrigation Land Leveling (464) Outlet Boise River Irrigation System, Sprinkler

Tier Number of Receiving Participating Acres Monitoring Treatment Producers Treated Period Tier 1 67.8 Tier 1 51.1

Outlet Boise River

Tier 1

67.8

Tier 1 Tier 1 Tier 1 Tier 1 Tier 1 Tier 1 Tier 1 Tier 1

48.9 13.3 80.6 80.6 41.9 41.8 13.3 6.8 2,289.5

Tier 2

64.1

Tier 2

33.1

Tier 2 Tier 2 Tier 2 Tier 2 Tier 2 Tier 2 Tier 2 Tier 2 Tier 2 Tier 2 Tier 2 Tier 2

23.1 33.1 101.7 43.2 23.7 27.0 27.0 27.0 27.0 49.2 35.2 49.2

Outlet Boise River Outlet Boise River Outlet Boise River Outlet Boise River Outlet Boise River Outlet Boise River Outlet Boise River Upper Indian Creek Tier I Total Acres Dixie Slough Dixie Slough Dixie Slough Dixie Slough Fifteen Mile Creek Low Line Canal Low Line Canal North Indian Creek North Indian Creek North Indian Creek North Indian Creek Outlet Boise River Outlet Boise River Outlet Boise River

Irrigation System, Surface and Subsurface (443) Irrigation Water Conveyance, Pipeline, HighPressure, Underground, Plastic (430DD) Irrigation Water Conveyance, Pipeline, Steel Irrigation Water Management (449) Nutrient Management (590) Pumping Plant (533) Structure for Water Control Wetland Restoration Structure for Water Control (587)

Irrigation System, Micro irrigation (441) Irrigation Water Conveyance, Pipeline, HighPressure, Underground, Plastic Irrigation Water Conveyance, Pipeline, Rigid Gated Pipeline Structure for Water Control Conservation Crop Rotation Conservation Crop Rotation (328) Irrigation Water Management (449) Conservation Crop Rotation Irrigation Water Management Residue Management, Seasonal Surface Roughening Conservation Crop Rotation (328) Irrigation System, Micro irrigation (441) Irrigation Water Management (449)

298

Lower Boise River 5-year Subbasin Assessment and TMDL Review

TMDL 6th Field Subwatershed Target Outlet Boise River Outlet Boise River Sough Slough Boise River Sough Slough Boise River Sough Slough Boise River Sough Slough Boise River South Slough Boise River South Slough Boise River South Slough Boise River Tier II Total Acres

February 2009 Tier Number of Receiving Participating Acres Monitoring Treatment Producers Treated Period Tier 2 49.2 Tier 2 5.5

Activity Nutrient Management (590) Pumping Plant (533) Anionic Polyacrylamide (PAM) Erosion Control Irrigation Water Conveyance, Ditch and Canal Lining, Plain Concrete

Tier 2

38.9

Tier 2

10.7

Irrigation Water Management

Tier 2

49.6

Pest Management Conservation Crop Rotation Irrigation Water Management Pest Management

Tier 2 Tier 2 Tier 2 Tier 2

49.6 28.2 49.6 49.6 894.5

Coulee Drain Lake Lowell Coulee Drain Lake Lowell Coulee Drain Lake Lowell Coulee Drain Lake Lowell Coulee Drain Lake Lowell Coulee Drain Lake Lowell Coulee Drain Lake Lowell

Comprehensive Nutrient Management Plan (100) Conservation Crop Rotation (328) Diversion (362) Fence (382) Forage Harvest Management Irrigation Regulating Reservoir Irrigation System, Sprinkler

Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3

36.2 150.1 5.0 15.2 29.2 21.7 145.1

Coulee Drain Lake Lowell Coulee Drain Lake Lowell

Irrigation System, Surface and Subsurface (443) Irrigation System, Tailwater Recovery Irrigation Water Conveyance, Pipeline, HighPressure, Underground, Plastic (430DD) Irrigation Water Conveyance, Pipeline, Rigid Gated Pipeline Irrigation Water Management Irrigation Water Management (449)

Tier 3 Tier 3

96.7 21.7

Tier 3

58.7

Tier 3 Tier 3 Tier 3

86.4 29.2 5.0

Coulee Drain Lake Lowell Coulee Drain Lake Lowell Mason Creek Coulee Drain Lake Lowell

299

Lower Boise River 5-year Subbasin Assessment and TMDL Review

TMDL 6th Field Subwatershed Target Coulee Drain Lake Lowell Coulee Drain Lake Lowell Coulee Drain Lake Lowell Coulee Drain Lake Lowell Coulee Drain Lake Lowell Coulee Drain Lake Lowell Coulee Drain Lake Lowell Coulee Drain Lake Lowell Coulee Drain Lake Lowell Coulee Drain Lake Lowell Coulee Drain Lake Lowell Coulee Drain Lake Lowell Currant Creek Dry Creek Currant Creek Dry Creek Eightmile Creek Eightmile Creek Eightmile Creek Eightmile Creek Eightmile Creek Eightmile Creek Eightmile Creek Eightmile Creek Eightmile Creek Fifteen Mile Creek Fifteen Mile Creek Fifteen Mile Creek Fifteen Mile Creek Fifteen Mile Creek

Activity Nutrient Management Pasture and Hay Planting (512) Pest Management Pipeline (516) Pumping Plant Residue Management, Seasonal (344) Roof Runoff Structure (558) Structure for Water Control Surface Roughening (609) Waste Storage Facility Watering Facility (614) Windbreak/Shelterbelt Establishment Irrigation System, Sprinkler (442) Nutrient Management (590) Fence (382) Irrigation System, Sprinkler Irrigation Water Conveyance, Pipeline, HighPressure, Underground, Plastic Irrigation Water Management (449) Nutrient Management (590) Pasture and Hay Planting Prescribed Grazing (528) Pumping Plant Structure for Water Control Irrigation System, Sprinkler (442) Irrigation Water Conveyance, Pipeline, HighPressure, Underground, Plastic (430DD) Nutrient Management (590) Pumping Plant (533) Structure for Water Control (587)

300

February 2009 Tier Number of Receiving Participating Acres Monitoring Treatment Producers Treated Period Tier 3 29.2 Tier 3 8.3 Tier 3 6.9 Tier 3 8.3 Tier 3 21.7 Tier 3 5.0 Tier 3 11.9 Tier 3 44.2 Tier 3 5.0 Tier 3 13.8 Tier 3 8.3 Tier 3 21.7 Tier 3 14.9 Tier 3 14.9 Tier 3 4.9 Tier 3 19.8 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3

14.9 19.8 19.8 11.9 11.9 11.9 23.8 98.9

Tier 3 Tier 3 Tier 3 Tier 3

98.9 17.2 22.8 63.4

Lower Boise River 5-year Subbasin Assessment and TMDL Review

TMDL 6th Field Subwatershed Target Kuna Butte Kuna Butte Kuna Butte Kuna Butte Kuna Butte Kuna Butte Kuna Butte Kuna Butte Kuna Butte Kuna Butte Low Line Canal Low Line Canal Low Line Canal Low Line Canal Lower Indian Creek Lower Indian Creek Lower Indian Creek Lower Indian Creek Lower Indian Creek Lower Indian Creek Lower Indian Creek Lower Indian Creek Lower Indian Creek Lower Indian Creek Lower Indian Creek Lower Indian Creek Lower Indian Creek

February 2009 Tier Number of Receiving Participating Acres Monitoring Treatment Producers Treated Period

Activity Anionic Polyacrylamide (PAM) Erosion Control Conservation Crop Rotation (328) Irrigation System, Sprinkler Irrigation System, Surface and Subsurface Irrigation Water Conveyance, Pipeline, Rigid Gated Pipeline Irrigation Water Management Nutrient Management Pest Management Residue Management, Seasonal Structure for Water Control Conservation Crop Rotation (328) Irrigation System, Sprinkler Irrigation Water Conveyance, Pipeline, LowPressure, Underground, Plastic Irrigation Water Management Conservation Crop Rotation (328) Forage Harvest Management Irrigation System, Sprinkler Irrigation System, Surface and Subsurface Irrigation System, Tailwater Recovery Irrigation Water Conveyance, Pipeline, HighPressure, Underground, Plastic Irrigation Water Management (449) Nutrient Management Pest Management Prescribed Grazing Pumping Plant Residue Management, Seasonal Structure for Water Control

301

Tier 3 Tier 3 Tier 3 Tier 3

76.2 79.9 29.0 51.4

Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3

23.8 76.2 65.4 76.2 76.2 8.4 149.0 94.8

Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3

71.5 0.8 161.3 67.6 33.8 42.3 33.5

Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3

96.6 127.5 117.7 117.7 12.0 96.6 34.6 33.5

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

TMDL 6th Field Subwatershed Target Activity Lower Indian Creek Surface Roughening Lower Indian Creek Windbreak/Shelterbelt Establishment Mason Creek Above Ground, Multi-Outlet Pipeline (431)

Tier Number of Receiving Participating Acres Monitoring Treatment Producers Treated Period Tier 3 34.6 Tier 3 33.5 Tier 3 37.4

Mason Creek

Comprehensive Nutrient Management Plan (100) Conservation Completion Incentive First Year (CCIA) Conservation Crop Rotation (328) Fence (382) Forage Harvest Management Irrigation System, Micro irrigation Irrigation System, Sprinkler (442)

Tier 3

32.3

Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3

32.3 412.1 41.5 100.8 76.0 175.8

Irrigation System, Surface and Subsurface (443) Irrigation Water Conveyance, Ditch and Canal Lining, Plain Concrete Irrigation Water Conveyance, Pipeline, HighPressure, Underground, Plastic (430DD) Irrigation Water Conveyance, Pipeline, Rigid Gated Pipeline Irrigation Water Conveyance, Pipeline, Steel (430FF) Irrigation Water Management (449) Land Smoothing (466) Nutrient Management (590) Pasture and Hay Planting (512) Pest Management Pipeline (516) Prescribed Grazing Pumping Plant (533) Residue Management, Seasonal (344) Sediment Basin (350)

Tier 3

142.5

Tier 3

49.7

Tier 3

151.5

Tier 3

51.8

Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3

47.0 390.0 3.4 349.3 63.6 333.4 62.4 83.9 121.8 147.9 60.5

Mason Creek Mason Creek Mason Creek Mason Creek Mason Creek Mason Creek Mason Creek Mason Creek Mason Creek Mason Creek Mason Creek Mason Creek Mason Creek Mason Creek Mason Creek Mason Creek Mason Creek Mason Creek Mason Creek Mason Creek Mason Creek

302

Lower Boise River 5-year Subbasin Assessment and TMDL Review

TMDL 6th Field Subwatershed Target Mason Creek Mason Creek Mason Creek North Indian Creek North Indian Creek North Indian Creek North Indian Creek North Indian Creek North Indian Creek North Indian Creek North Indian Creek North Indian Creek North Indian Creek North Indian Creek North Indian Creek North Indian Creek North Indian Creek Outlet Boise River Outlet Boise River Outlet Boise River Outlet Boise River Outlet Boise River Outlet Boise River Outlet Boise River Outlet Boise River Outlet Boise River

Activity Structure for Water Control (587) Surface Roughening (609) Watering Facility (614) Forage Harvest Management Irrigation Regulating Reservoir Irrigation System, Sprinkler Irrigation System, Surface and Subsurface Irrigation Water Conveyance, Pipeline, HighPressure, Underground, Plastic Irrigation Water Conveyance, Pipeline, Rigid Gated Pipeline Irrigation Water Management Nutrient Management (590) Pest Management Pipeline Prescribed Grazing Pumping Plant Structure for Water Control Windbreak/Shelterbelt Establishment Above Ground, Multi-Outlet Pipeline (431) Comprehensive Nutrient Management Plan Conservation Completion Incentive First Year Conservation Completion Incentive First Year (CCIA) Conservation Crop Rotation (328) Irrigation System, Micro irrigation (441) Irrigation System, Sprinkler (442) Irrigation Water Conveyance, Pipeline, HighPressure, Underground, Plastic (430DD) Irrigation Water Conveyance, Pipeline, LowPressure, Underground, Plastic

303

February 2009 Tier Number of Receiving Participating Acres Monitoring Treatment Producers Treated Period Tier 3 182.6 Tier 3 147.9 Tier 3 65.9 Tier 3 44.9 Tier 3 33.5 Tier 3 124.1 Tier 3 28.5 Tier 3

32.4

Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3

1.6 46.7 44.9 72.5 3.5 1.4 47.4 60.0 18.2 39.7 29.8

Tier 3

21.4

Tier 3 Tier 3 Tier 3 Tier 3

29.8 328.7 66.8 180.4

Tier 3

53.4

Tier 3

16.2

Lower Boise River 5-year Subbasin Assessment and TMDL Review

TMDL 6th Field Subwatershed Target Outlet Boise River Outlet Boise River Outlet Boise River Outlet Boise River Outlet Boise River Outlet Boise River Outlet Boise River Outlet Boise River South Slough Boise River South Slough Boise River South Slough Boise River South Slough Boise River Tier III Total Acres

February 2009 Tier Number of Receiving Participating Acres Monitoring Treatment Producers Treated Period

Activity Irrigation Water Conveyance, Pipeline, Steel (430FF) Irrigation Water Management (449) Nutrient Management (590) Pasture and Hay Planting (512) Pest Management (595) Prescribed Grazing (528) Pumping Plant (533) Structure for Water Control (587)

Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3 Tier 3

32.4 475.1 289.9 10.0 144.1 10.0 104.4 31.0

Anionic Polyacrylamide (PAM) Erosion Control Irrigation Water Management Nutrient Management Pest Management

Tier 3 Tier 3 Tier 3 Tier 3

10.2 20.4 20.4 20.4 9,097.0

Total Acres %Tier I % Tier II % Tier III Tier I = High priority; Tier II = Medium priority; Tier III = Low priority.

12,281.0 18.6 7.3 74.1

304

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Appendix E. Assessment Unit Maps

305

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure E-1. Lower Boise River Assessment Unit 001(Lower Boise River from Indian Creek to the mouth), with surface water bodies and potential surface water pollutant sources.

306

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure E-2. Lower Boise River Assessment Unit 002 and 003 (Indian Creek), with surface water bodies and potential surface water pollutant sources.

307

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure E-3. Lower Boise River Assessment Unit 005 (Boise River from Glenwood Bridge to Indian Creek and Mill Slough), with surface water bodies and potential surface water pollutant sources.

308

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure E-4. Lower Boise River Assessment Unit 006 (Mason Creek), with surface water bodies and potential surface water pollutant sources.

309

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure E-5. Lower Boise River Assessment Unit 007 (Fifteenmile Creek), with surface water bodies and potential surface water pollutant sources.

310

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure E-6. Lower Boise River Assessment Unit 008 (Tenmile Creek), with surface water bodies and potential surface water pollutant sources.

311

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure E-7. Lower Boise River Assessment Unit 009 (Blacks Creek), with surface water bodies and potential surface water pollutant sources.

312

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure E-8. Lower Boise River Assessment Unit 010 (Fivemile Creek), with surface water bodies and potential surface water pollutant sources.

313

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure E-9. Lower Boise River Assessment Unit 011 (Boise River from Lucky Peak outfall to Glenwood Bridge), with surface water bodies and potential surface water pollutant sources.

314

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure E-10. Lower Boise River Assessment Unit 012 (Cottonwood Creek, and various springs) with surface water bodies and potential surface water pollutant sources.

315

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure E-11. Lower Boise Assessment Unit 013 (Dry Creek), with surface water bodies and potential surface water pollutant sources.

316

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure E-12. Lower Boise Assessment Unit 014 (Big and Little Gulch complex), with surface water bodies and potential surface water pollutant sources.

317

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure E-13. Lower Boise Assessment Unit 015 (Willow Creek), with surface water bodies and potential surface water pollutant sources.

318

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure E-14. Lower Boise Assessment Unit 016 (Langley/Graveyard Gulch complex), with surface water bodies and potential surface water pollutant sources.

319

Lower Boise River 5-year Subbasin Assessment and TMDL Review

February 2009

Figure E-15. Lower Boise Assessment Unit 017 (Sand Hollow Creek), with surface water bodies and potential surface water pollutant sources.

320

Lower Boise River 5-year Subbasin Assessment and TMDL Review

321

February 2009

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Lower Boise River - Boise River Enhancement Network

Lower Boise River TMDL Five-Year Review Final Department of Environmental Quality February 2009 Lower Boise River 5-year Subbasin Assessment and T...

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