Idea Transcript
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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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 (