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Site-specific Targeted Monitoring Summary Results

Idaho (2010)

Description of this table

	Size of Water
	Rivers and Streams (Miles)	Lakes, Reservoirs, and Ponds (Acres)
Good Waters	27,893.7	22,034.1
Previously impaired waters       now attaining all uses	483.3	966.2
Threatened Waters	48.5
TMDL completed	48.5
TMDL alternative
Non-pollutant impairment
TMDL needed
Impaired Waters	33,983.7	261,069.6
TMDL completed	16,246.9	51,117.8
TMDL alternative	39.6
Non-pollutant impairment	488.9	1,916.3
TMDL needed	17,208.2	208,035.6
New TMDLs completed	1,684.3	.0
Remaining TMDLs needed	15,524.0	208,035.6
Total Assessed Waters	61,925.8	283,103.7
Total Waters	96,391.0	475,457.4
Percent of Waters Assessed	64.2	59.5

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Summary of Water Quality Assessments for Each Waterbody Type
for Reporting Year 2010

Site-specific Targeted Monitoring Results

Idaho Rivers and Streams 2010

Description of this table Assessed Status Miles Assessed 61,925.8 Unassessed 34,465.2 Total Miles 96,391.0

Description of this table Attainment Status Miles Good 27,893.7 Threatened 48.5 Impaired 33,983.7 Total Miles Assessed 61,925.8

Description of this table TMDL Development Status Miles All TMDLs completed 17,979.6 TMDL alternative 39.6 Non-pollutant impairment 488.9 TMDL needed 15,524.0 Total Threatened and Impaired 34,032.1

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Site-specific Targeted Monitoring Results

Individual Designated Use Support
Idaho Rivers and Streams 2010

* Waters assessed for more than one designated use are included in multiple designated use groups below.

Description of this table

Designated Use	Miles Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
					% Threatened
					% Impaired
Aesthetic	5,427.4	100.0	.0	.0
Agricultural Water Supply	7,194.8	99.1	.0	.9
Cold Water Aquatic Life	60,900.3	47.0	.1	52.9
Domestic Water Supply	4,246.6	95.3	.0	4.7
Industrial Water Supply	6,991.2	100.0	.0	.0
Modified Aquatic Life	3.7	.0	.0	100.0
Primary Contact Recreation	16,796.1	80.0	.0	20.0
Salmonid Spawning	33,356.4	56.2	.2	43.6
Seasonal Cold Water Aquatic Life	13.5	100.0	.0	.0
Secondary Contact Recreation	25,317.9	85.1	.0	14.9
Undesignated Surface Waters	19.8	.0	.0	100.0
Warm Water Aquatic Life	148.4	32.0	.0	68.0
Wildlife Habitat	6,985.4	100.0	.0	.0

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Site-specific Targeted Monitoring Results

Causes of Impairment
Idaho Rivers and Streams 2010

Description of this table

Cause of Impairment	Cause of Impairment Group	Miles Threatened or Impaired
Temperature, Water	Temperature	17,900.6
Sedimentation/Siltation	Sediment	16,654.2
Phosphorus, Total	Nutrients	5,325.6
Combined Biota/Habitat Bioassessments (Streams)	Cause Unknown - Impaired Biota	4,984.4
Other Flow Regime Alterations	Flow Alteration(s)	3,808.2
Escherichia Coli (E. Coli)	Pathogens	3,769.1
Physical Substrate Habitat Alterations	Habitat Alterations	3,698.9
Fecal Coliform	Pathogens	3,189.9
Cause Unknown	Cause Unknown	2,002.4
Total Suspended Solids (TSS)	Turbidity	1,914.7
Low Flow Alterations	Flow Alteration(s)	1,696.3
Nutrient/Eutrophication Biological Indicators	Nutrients	1,678.4
Dissolved Oxygen	Organic Enrichment/Oxygen Depletion	922.2
Nitrogen, Total	Nutrients	533.4
Habitat Assessment (Streams)	Cause Unknown - Impaired Biota	530.4
Oil and Grease	Oil and Grease	503.6
Ammonia, Un-ionized	Ammonia	470.4
Fish Bioassessments	Cause Unknown - Impaired Biota	421.3
Zinc	Metals (other than Mercury)	342.1
Cadmium	Metals (other than Mercury)	337.9
Mercury	Mercury	310.3
Lead	Metals (other than Mercury)	271.8
Benthic Macroinvertebrates Bioassessments	Cause Unknown - Impaired Biota	233.2
Dissolved Gas Supersaturation	Other Cause	163.5
Selenium	Metals (other than Mercury)	151.9
pH	pH/Acidity/Caustic Conditions	83.9
Copper	Metals (other than Mercury)	42.2
Chlorpyrifos	Pesticides	33.6
Total Coliform	Pathogens	24.6
Arsenic	Metals (other than Mercury)	10.4
Fish Kill(s)	Cause Unknown - Fish Kills	10.0
Aquatic Plant Bioassessments	Cause Unknown - Impaired Biota	9.7
Nitrogen, Nitrate	Nutrients	9.0
High Flow Regime	Flow Alteration(s)	4.9
Aquatic Plants (Macrophytes)	Noxious Aquatic Plants	4.7
Particle Distribution (Embeddedness)	Sediment	3.0

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Site-specific Targeted Monitoring Results

Probable Sources
Idaho Rivers and Streams 2010

Description of this table

Probable Source	Probable Source Group	Miles Threatened or Impaired
Grazing In Riparian Or Shoreline Zones	Agriculture	2,292.4
Rangeland Grazing	Agriculture	1,876.6
Livestock (Grazing Or Feeding Operations)	Agriculture	1,173.3
Loss Of Riparian Habitat	Habitat Alterations (Not Directly Related To Hydromodification)	628.8
Source Unknown	Unknown	619.9
Managed Pasture Grazing	Agriculture	581.0
Flow Alterations From Water Diversions	Hydromodification	558.4
Natural Sources	Natural/Wildlife	548.6
Impacts From Hydrostructure Flow Regulation/Modification	Hydromodification	525.7
Channelization	Hydromodification	494.8
Irrigated Crop Production	Agriculture	412.6
Streambank Modifications/Destabilization	Hydromodification	372.8
Silviculture Activities	Silviculture (Forestry)	310.9
Agriculture	Agriculture	300.0
Highway/Road/Bridge Runoff (Non-Construction Related)	Urban-Related Runoff/Stormwater	281.1
Impacts From Abandoned Mine Lands (Inactive)	Resource Extraction	266.9
Upstream Impoundments (E.G., Pl-566 Nrcs Structures)	Hydromodification	259.9
Forest Roads (Road Construction And Use)	Silviculture (Forestry)	235.9
Placer Mining	Resource Extraction	224.4
Habitat Modification - Other Than Hydromodification	Habitat Alterations (Not Directly Related To Hydromodification)	136.2
Crop Production (Crop Land Or Dry Land)	Agriculture	106.3
Non-Irrigated Crop Production	Agriculture	98.7
Construction Stormwater Discharge (Permitted)	Construction	69.6
Highways, Roads, Bridges, Infrastructure (New Construction)	Construction	68.8
Municipal Point Source Discharges	Municipal Discharges/Sewage	63.9
Dam Construction (Other Than Upstream Flood Control Projects)	Hydromodification	62.0
Animal Feeding Operations (Nps)	Agriculture	53.1
Surface Mining	Resource Extraction	49.5
Site Clearance (Land Development Or Redevelopment)	Construction	39.7
Mill Tailings	Industrial	39.3
Sources Outside State Jurisdiction Or Borders	Other	37.9
Wet Weather Discharges (Point Source And Combination Of Stormwater, Sso Or Cso)	Municipal Discharges/Sewage	31.2
Acid Mine Drainage	Resource Extraction	31.2
Dredging (E.G., For Navigation Channels)	Hydromodification	30.9
Mine Tailings	Resource Extraction	28.2
Other Recreational Pollution Sources	Recreation And Tourism (Non-Boating)	18.5
Aquaculture (Permitted)	Aquaculture	14.3
Post-Development Erosion And Sedimentation	Hydromodification	10.4
Dam Or Impoundment	Hydromodification	10.1
Subsurface (Hardrock) Mining	Resource Extraction	2.0
Dredge Mining	Resource Extraction	2.0

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Site-specific Targeted Monitoring Results

Idaho Lakes, Reservoirs, and Ponds 2010

Description of this table Assessed Status Acres Assessed 283,103.7 Unassessed 192,353.7 Total Acres 475,457.4

Description of this table Attainment Status Acres Good 22,034.1 Threatened .0 Impaired 261,069.6 Total Acres Assessed 283,103.7

Description of this table TMDL Development Status Acres All TMDLs completed 51,117.8 TMDL alternative .0 Non-pollutant impairment 1,916.3 TMDL needed 208,035.6 Total Threatened and Impaired 261,069.6

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Site-specific Targeted Monitoring Results

Individual Designated Use Support
Idaho Lakes, Reservoirs, and Ponds 2010

* Waters assessed for more than one designated use are included in multiple designated use groups below.

Description of this table

Designated Use	Acres Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
					% Threatened
					% Impaired
Aesthetic	2,184.9	100.0	.0	.0
Agricultural Water Supply	2,179.2	100.0	.0	.0
Cold Water Aquatic Life	281,855.8	7.9	.0	92.1
Domestic Water Supply	666.9	100.0	.0	.0
Industrial Water Supply	2,184.9	100.0	.0	.0
Primary Contact Recreation	58,804.7	97.3	.0	2.7
Salmonid Spawning	93,736.7	13.8	.0	86.2
Seasonal Cold Water Aquatic Life	966.2	.0	.0	100.0
Secondary Contact Recreation	118,870.1	1.1	.0	98.9
Undesignated Surface Waters	202.6	.0	.0	100.0
Warm Water Aquatic Life	6,094.0	.6	.0	99.4
Wildlife Habitat	2,184.9	100.0	.0	.0

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Site-specific Targeted Monitoring Results

Causes of Impairment
Idaho Lakes, Reservoirs, and Ponds 2010

Description of this table

Cause of Impairment	Cause of Impairment Group	Acres Threatened or Impaired
Phosphorus, Total	Nutrients	147,598.9
Mercury	Mercury	119,934.7
Other Flow Regime Alterations	Flow Alteration(s)	84,683.9
Sedimentation/Siltation	Sediment	81,843.8
Dissolved Oxygen	Organic Enrichment/Oxygen Depletion	64,288.7
Nutrient/Eutrophication Biological Indicators	Nutrients	55,946.7
Chlorophyll-A	Algal Growth	55,519.2
Zinc	Metals (other than Mercury)	27,968.3
Lead	Metals (other than Mercury)	27,968.3
Cadmium	Metals (other than Mercury)	27,968.3
pH	pH/Acidity/Caustic Conditions	25,395.0
Temperature, Water	Temperature	21,746.4
Dissolved Gas Supersaturation	Other Cause	3,616.4
Total Suspended Solids (TSS)	Turbidity	1,887.9
Low Flow Alterations	Flow Alteration(s)	1,045.3
Aquatic Algae	Algal Growth	966.2
Escherichia Coli (E. Coli)	Pathogens	507.2
Cause Unknown	Cause Unknown	375.6
Physical Substrate Habitat Alterations	Habitat Alterations	86.5
Nitrogen, Total	Nutrients	66.7

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Site-specific Targeted Monitoring Results

Probable Sources
Idaho Lakes, Reservoirs, and Ponds 2010

No probable sources of impairments reported.

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Idaho Causes of Impairment for Reporting Year 2010

Description of this table

NOTE: Click on the underlined Cause of Impairment Group to see a list of specific state causes of impairment making up the Cause of Impairment Group. See also Pollution categories summary document (PDF) (20 pp, 557K, About PDF) for brief, non-technical descriptions of general cause categories.
Cause of Impairment Group	Size of Assessed Waters with Listed Causes of Impairment
	Rivers and Streams (Miles)	Lakes, Reservoirs, and Ponds (Acres)
Algal Growth		56,485.4
Ammonia	470.4
Cause Unknown	2,002.4	375.6
Cause Unknown - Fish Kills	10.0
Cause Unknown - Impaired Biota	5,295.6
Flow Alteration(s)	5,485.2	85,729.2
Habitat Alterations	3,698.9	86.5
Mercury	310.3	119,934.7
Metals (other than Mercury)	514.0	27,968.3
Noxious Aquatic Plants	4.7
Nutrients	6,975.2	203,545.6
Oil and Grease	503.6
Organic Enrichment/Oxygen Depletion	922.2	64,288.7
Other Cause	163.5	3,616.4
Pathogens	6,905.4	507.2
Pesticides	33.6
pH/Acidity/Caustic Conditions	83.9	25,395.0
Sediment	16,654.2	81,843.8
Temperature	17,900.6	21,746.4
Turbidity	1,914.7	1,887.9

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Idaho Probable Sources Contributing to Impairments
for Reporting Year 2010

Description of this table

NOTE: Click on the underlined Probable Source Group to see a list of specific state Probable Sources making up the Probable Source Group.
Probable Source Group	Size of Assessed Waters with Probable Sources of Impairments
	Rivers and Streams (Miles)	Lakes, Reservoirs, and Ponds (Acres)
Agriculture	4,472.3
Aquaculture	14.3
Construction	115.0
Habitat Alterations (Not Directly Related To Hydromodification)	657.6
Hydromodification	1,172.7
Industrial	39.3
Municipal Discharges/Sewage	82.1
Natural/Wildlife	548.6
Other	37.9
Recreation And Tourism (Non-Boating)	18.5
Resource Extraction	326.9
Silviculture (Forestry)	494.3
Unknown	619.9
Urban-Related Runoff/Stormwater	281.1

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Idaho TMDL Alternatives by Cause of Impairment 2010

Description of this table

NOTE: Click on the underlined "Number of TMDL Alternatives by Cause of Impairment " value to see a listing of those Causes of Impairment.
Cause of Impairment	Number of TMDL Alternatives	Rivers and Streams (Miles)
Sedimentation/Siltation	4	51

Total: 4 TMDL Alternatives

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Idaho Previously 303(d)-Listed Waters Now Attaining All Applicable Water Quality Standards

Description of this table

NOTE: Click on the underlined "Number of Waters Attaining" value for a detailed list of those previously 303(d)-listed waters now attaining all applicable water quality standards.
Year Attaining	Number of Waters Attaining	Number of Causes of Impairment Addressed
2009	26	33
2011	15	22

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Idaho Causes of Impairment for 303(d) Listed Waters

Description of this table

NOTE: Click on a cause of impairment (e.g. pathogens) to see the specific state-reported causes that are grouped to make up this category. Click on the "Number of Causes of Impairment Reported" to see a list of waters with that cause of impairment.
Cause of Impairment Group Name	Number of Causes of Impairment Reported
Temperature	381
Cause Unknown - Impaired Biota	230
Sediment	204
Pathogens	175
Metals (other than Mercury)	107
Cause Unknown	75
Mercury	22
Nutrients	21
Organic Enrichment/Oxygen Depletion	10
Ammonia	9
Oil and Grease	8
Other Cause	7
pH/Acidity/Caustic Conditions	2
Pesticides	2
Turbidity	2
Cause Unknown - Fish Kills	1
Flow Alteration(s)	1
Algal Growth	1

Total: 1,258 Causes of Impairment

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Idaho Cumulative TMDLs by Pollutant

This chart includes TMDLs since October 1, 1995.

Description of this table

NOTE: Click on the underlined "Pollutant" value to see associated listed waters for which a TMDL was developed. Click on the underlined "Number of TMDLs" value to see a listing of those TMDLs for the pollutant.
Pollutant	Number of TMDLs	Number of Causes of Impairment Addressed
Temperature	658	658
Sediment	400	400
Total Suspended Solids (TSS)	159	159
Phosphorus, Total	124	132
Nutrients	111	111
Phosphorus	92	96
Escherichia Coli (E. Coli)	65	65
Cadmium	60	60
Zinc	60	60
Lead	57	57
Bacteria	50	50
Dissolved Oxygen	26	26
Pathogens	18	18
Enterococcus Bacteria	10	10
Total Dissolved Gas	6	6
DDD	5	5
DDE	5	5
DDT	5	5
Dieldrin	5	5
Nitrite/Nitrate	5	5
Suspended Sediment	5	5
Erosion	4	4
Nitrogen, Total	4	4
Ammonia	3	3
Copper	3	3
Nitrogen	3	3
Oil and Grease	2	2
Total Inorganic Nitrogen	2	2
Turbidity	2	2
Chlorophyll-A	1	1
Mercury	1	1

Total: 1,951 TMDLs; 1,963 Causes of Impairment Addressed

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Idaho Cumulative Number of TMDLs

EPA Fiscal Year starts October 1 and ends September 30.

Description of this table

NOTE: Click on the underlined "Number of TMDLs Completed" value for a detailed list of the TMDLs for the fiscal year.
Fiscal Year	Number of TMDLs	Number of Causes of Impairment Addressed
1996	4	4
1997	14	14
1998	5	5
1999	19	21
2000	375	375
2001	72	75
2002	82	82
2003	120	120
2004	240	242
2005	160	160
2006	146	150
2007	50	50
2008	232	232
2009	93	93
2010	84	84
2011	36	37
2012	183	183
2013	36	36

Total: 1,951 TMDLs; 1,963 Causes of Impairment Addressed

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Idaho Cumulative Number of TMDLs for Indian Country Waters

EPA Fiscal Year starts October 1 and ends September 30.

Description of this table

NOTE:Click on the underlined "Number of TMDLs" value for a detailed list of the TMDLs for the fiscal year.
Fiscal Year	Number of TMDLs	Number of Causes of Impairment Addressed
1999	9	9
2000	124	124
2004	11	17
2005	1	10
2011	1	1
2012	36	36

Total: 182 TMDLs; 0 Causes of Impairment

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