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On This Page 303(d) Listed Waters for 2012

Data are also available for these cycles:
2002 2004 2006 2008 2010

Waterbody Changes from Prior Cycle

For More Information:

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State Water Quality Program Exit EPA Disclaimer

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Montana Water Quality Assessment Report

Assessed Waters of Montana by Watershed

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Search for a waterbody within Montana
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Display impaired waters and TMDL information only



Site-specific Targeted Monitoring Summary Results

Montana (2012)

Description of this table
 
    3,022.5 69,518.1
       144.9
    6,035.8
                2,680.0
                
                6.8
                3,349.0
    17,263.3 489,975.5
           2,438.1     1,900.0
                
           1,867.7     9,895.0
           12,957.5     478,180.5
              584.9     .0
                    12,372.6           478,180.5
20,285.8 565,529.4
176,750.0 844,802.0
11.5 66.9

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Summary of Water Quality Assessments for Each Waterbody Type
for Reporting Year 2012


Site-specific Targeted Monitoring Results

Montana Rivers and Streams 2012

Description of this table

All
Rivers and Streams

176,750.0 Miles of Rivers and Streams

Assessed 20,285.8
Unassessed 156,464.2
Total Miles 176,750.0







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Description of this table

Assessed
Rivers and Streams

20,285.8 Miles of
Assessed Rivers and Streams

Good 3,022.5
Threatened .0
Impaired 17,263.3
Total Miles Assessed 20,285.8







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Description of this table

Threatened and Impaired
Rivers and Streams

17,263.3 Miles of
Threatened and Impaired
Rivers and Streams

3,023.0
.0
1,867.7
12,372.6
Total Threatened and Impaired 17,263.3

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Site-specific Targeted Monitoring Results

Individual Designated Use Support
Montana Rivers and Streams 2012

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

Description of this table
% Good
% Threatened
% Impaired
Agricultural 14,327.8 85.2 .0 14.8 color.gifcolor.gif
Aquatic Life 18,970.5 16.1 .0 83.9 color.gifcolor.gif
Drinking Water 12,178.2 70.2 .0 29.8 color.gifcolor.gif
Primary Contact Recreation 15,891.8 60.7 .0 39.3 color.gifcolor.gif

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Site-specific Targeted Monitoring Results

Causes of Impairment
Montana Rivers and Streams 2012

Description of this table
Alteration in Stream-Side or Littoral Vegetative Covers Habitat Alterations color.gif 8,352.3
Sedimentation/Siltation Sediment color.gif 7,343.7
Low Flow Alterations Flow Alteration(s) color.gif 4,989.4
Phosphorus, Total Nutrients color.gif 4,959.4
Nitrogen, Total Nutrients color.gif 4,749.2
Physical Substrate Habitat Alterations Habitat Alterations color.gif 3,525.2
Lead Metals (other than Mercury) color.gif 3,344.6
Copper Metals (other than Mercury) color.gif 3,139.3
Temperature, Water Temperature color.gif 2,711.3
Iron Metals (other than Mercury) color.gif 2,328.7
Nitrate/Nitrite (Nitrite + Nitrate as N) Nutrients color.gif 2,243.8
Mercury Mercury color.gif 1,850.0
Cadmium Metals (other than Mercury) color.gif 1,757.5
Zinc Metals (other than Mercury) color.gif 1,711.6
Salinity Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 1,698.9
Chlorophyll-A Algal Growth color.gif 1,542.1
Arsenic Metals (other than Mercury) color.gif 1,526.9
Other Flow Regime Alterations Flow Alteration(s) color.gif 1,402.8
Solids (Suspended/Bedload) Sediment color.gif 1,386.4
Total Dissolved Solids (TDS) Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 1,308.9
Sulfates Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 703.3
Escherichia Coli (E. Coli) Pathogens color.gif 527.3
Fish Passage Barrier Habitat Alterations color.gif 521.9
Total Kjehldahl Nitrogen (TKN) Nutrients color.gif 501.5
Dissolved Oxygen Organic Enrichment/Oxygen Depletion color.gif 494.2
Specific Conductivity Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 473.3
Other Anthropogenic Substrate Alterations Habitat Alterations color.gif 398.0
Excess Algal Growth Algal Growth color.gif 360.6
pH pH/Acidity/Caustic Conditions color.gif 353.6
Selenium Metals (other than Mercury) color.gif 340.6
Aluminum Metals (other than Mercury) color.gif 328.4
Chromium, Total Metals (other than Mercury) color.gif 308.9
Nitrogen, Nitrate Nutrients color.gif 307.3
Nitrates Nutrients color.gif 269.6
Cause Unknown Cause Unknown color.gif 229.7
Ammonia, Un-ionized Ammonia color.gif 221.6
Nickel Metals (other than Mercury) color.gif 204.0
Organic Enrichment (Sewage) Biological Indicators Organic Enrichment/Oxygen Depletion color.gif 186.9
Turbidity Turbidity color.gif 168.6
High Flow Regime Flow Alteration(s) color.gif 160.7
Silver Metals (other than Mercury) color.gif 153.0
Manganese Metals (other than Mercury) color.gif 153.0
Total Suspended Solids (TSS) Turbidity color.gif 125.3
Oil and Grease Oil and Grease color.gif 114.0
Other Cause Other Cause color.gif 111.6
Cyanide Toxic Inorganics color.gif 91.5
Uranium Radiation color.gif 86.9
Benthic Macroinvertebrates Bioassessments Cause Unknown - Impaired Biota color.gif 84.8
Antimony Toxic Inorganics color.gif 78.1
Sodium Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 75.7
Ammonia, Total Ammonia color.gif 68.6
Biochemical Oxygen Demand (BOD) Organic Enrichment/Oxygen Depletion color.gif 64.2
Polychlorinated Biphenyls (PCBs) Polychlorinated Biphenyls (PCBs) color.gif 47.3
Alterations in Wetland Habitats Habitat Alterations color.gif 46.9
Nutrient/Eutrophication Biological Indicators Nutrients color.gif 37.2
Bottom Deposits Sediment color.gif 30.6
PCB in Water Column Polychlorinated Biphenyls (PCBs) color.gif 24.8
DDE Pesticides color.gif 22.1
Polycyclic Aromatic Hydrocarbons (PAHs) (Aquatic Ecosystems) Toxic Organics color.gif 21.8
Dissolved Gas Supersaturation Other Cause color.gif 18.9
Chloride Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 17.6
Mercury in Water Column Mercury color.gif 17.6
Combined Biota/Habitat Bioassessments (Streams) Cause Unknown - Impaired Biota color.gif 13.4
Aquatic Plants - Native Nuisance Native Species color.gif 13.0
Barium Radiation color.gif 12.0
Cobalt Metals (other than Mercury) color.gif 12.0
Non-Native Fish/Shellfish/Zooplankton Nuisance Exotic Species color.gif 11.0
Dissolved Oxygen Saturation Organic Enrichment/Oxygen Depletion color.gif 10.7
Periphyton (Aufwuchs) Indicator Bioassessments (Streams) Cause Unknown - Impaired Biota color.gif 10.7
Thallium Metals (other than Mercury) color.gif 7.9
Fecal Coliform Pathogens color.gif 6.2
Beryllium Metals (other than Mercury) color.gif 5.4

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Site-specific Targeted Monitoring Results

Probable Sources
Montana Rivers and Streams 2012

Description of this table
Agriculture Agriculture color.gif 5,935.7
Grazing In Riparian Or Shoreline Zones Agriculture color.gif 5,645.9
Source Unknown Unknown color.gif 4,664.1
Irrigated Crop Production Agriculture color.gif 4,547.3
Natural Sources Natural/Wildlife color.gif 4,513.3
Streambank Modifications/Destabilization Hydromodification color.gif 2,575.2
Impacts From Hydrostructure Flow Regulation/Modification Hydromodification color.gif 2,329.4
Rangeland Grazing Agriculture color.gif 2,190.4
Impacts From Abandoned Mine Lands (Inactive) Resource Extraction color.gif 2,033.5
Channelization Hydromodification color.gif 1,974.2
Loss Of Riparian Habitat Habitat Alterations (Not Directly Related To Hydromodification) color.gif 1,887.6
Flow Alterations From Water Diversions Hydromodification color.gif 1,452.8
Dam Or Impoundment Hydromodification color.gif 1,350.7
Highways, Roads, Bridges, Infrastructure (New Construction) Construction color.gif 1,187.8
Forest Roads (Road Construction And Use) Silviculture (Forestry) color.gif 1,009.5
Silviculture Activities Silviculture (Forestry) color.gif 880.0
Municipal Point Source Discharges Municipal Discharges/Sewage color.gif 749.9
Acid Mine Drainage Resource Extraction color.gif 698.9
Crop Production (Crop Land Or Dry Land) Agriculture color.gif 679.7
Highway/Road/Bridge Runoff (Non-Construction Related) Urban-Related Runoff/Stormwater color.gif 679.4
Non-Irrigated Crop Production Agriculture color.gif 678.7
Unspecified Unpaved Road Or Trail Urban-Related Runoff/Stormwater color.gif 585.2
Site Clearance (Land Development Or Redevelopment) Construction color.gif 579.1
Dam Construction (Other Than Upstream Flood Control Projects) Hydromodification color.gif 539.1
Mine Tailings Resource Extraction color.gif 520.1
Silviculture Harvesting Silviculture (Forestry) color.gif 508.6
Habitat Modification - Other Than Hydromodification Habitat Alterations (Not Directly Related To Hydromodification) color.gif 485.6
Animal Feeding Operations (Nps) Agriculture color.gif 447.1
Mill Tailings Industrial color.gif 408.2
Contaminated Sediments Legacy/Historical Pollutants color.gif 289.9
Subsurface (Hardrock) Mining Resource Extraction color.gif 260.2
Industrial Point Source Discharge Industrial color.gif 234.7
Placer Mining Resource Extraction color.gif 234.1
Transfer Of Water From An Outside Watershed Hydromodification color.gif 196.1
Dredge Mining Resource Extraction color.gif 157.7
Hydrostructure Impacts On Fish Passage Hydromodification color.gif 140.4
Drought-Related Impacts Natural/Wildlife color.gif 133.8
Livestock (Grazing Or Feeding Operations) Agriculture color.gif 130.3
Surface Mining Resource Extraction color.gif 120.0
Above Ground Storage Tank Leaks (Tank Farms) Spills/Dumping color.gif 117.3
Post-Development Erosion And Sedimentation Hydromodification color.gif 116.7
Residential Districts Urban-Related Runoff/Stormwater color.gif 115.3
Pipeline Breaks Spills/Dumping color.gif 111.0
Managed Pasture Grazing Agriculture color.gif 107.3
Watershed Runoff Following Forest Fire Silviculture (Forestry) color.gif 101.7
Impacts From Resort Areas (Winter And Non-Winter Resorts) Recreation And Tourism (Non-Boating) color.gif 97.4
Golf Courses Recreation And Tourism (Non-Boating) color.gif 96.8
On-Site Treatment Systems (Septic Systems And Similar Decentralized Systems) Municipal Discharges/Sewage color.gif 96.2
Wet Weather Discharges (Point Source And Combination Of Stormwater, Sso Or Cso) Municipal Discharges/Sewage color.gif 82.7
Hardrock Mining Discharges (Permitted) Resource Extraction color.gif 77.7
Upstream Impoundments (E.G., Pl-566 Nrcs Structures) Hydromodification color.gif 77.3
Upstream Source Other color.gif 76.3
Coal Mining Resource Extraction color.gif 66.5
Permitted Runoff From Confined Animal Feeding Operations (Cafos) Agriculture color.gif 64.2
Atmospheric Deposition - Nitrogen Atmospheric Deposition color.gif 62.9
Channel Erosion/Incision From Upstream Hydromodifications Hydromodification color.gif 55.3
Low Water Crossing Other color.gif 51.6
Aquaculture (Permitted) Aquaculture color.gif 51.4
Crop Production With Subsurface Drainage Agriculture color.gif 45.3
Sand/Gravel/Rock Mining Or Quarries Resource Extraction color.gif 41.3
Yard Maintenance Urban-Related Runoff/Stormwater color.gif 37.7
Unspecified Urban Stormwater Urban-Related Runoff/Stormwater color.gif 31.1
Sediment Resuspension (Clean Sediment) Hydromodification color.gif 28.9
Atmospheric Deposition - Toxics Atmospheric Deposition color.gif 28.6
Spills From Trucks Or Trains Spills/Dumping color.gif 27.5
Coal Mining Discharges (Permitted) Resource Extraction color.gif 24.1
Sediment Resuspension (Contaminated Sediment) Hydromodification color.gif 23.6
Other Recreational Pollution Sources Recreation And Tourism (Non-Boating) color.gif 22.6
Petroleum/Natural Gas Production Activities (Permitted) Industrial color.gif 21.8
Wet Weather Discharges (Non-Point Source) Urban-Related Runoff/Stormwater color.gif 15.0
Construction Stormwater Discharge (Permitted) Construction color.gif 14.3
Discharges From Municipal Separate Storm Sewer Systems (Ms4) Urban-Related Runoff/Stormwater color.gif 13.2
Freshets Or Major Flooding Natural/Wildlife color.gif 11.6
Open Pit Mining Resource Extraction color.gif 10.6
Septage Disposal Municipal Discharges/Sewage color.gif 9.8
Municipal (Urbanized High Density Area) Urban-Related Runoff/Stormwater color.gif 7.3
Industrial/Commercial Site Stormwater Discharge (Permitted) Urban-Related Runoff/Stormwater color.gif 7.0
Waterfowl Natural/Wildlife color.gif 6.2
Wastes From Pets Urban-Related Runoff/Stormwater color.gif 6.2
Baseflow Depletion From Groundwater Withdrawals Hydromodification color.gif 4.8
Heap-Leach Extraction Mining Resource Extraction color.gif 3.8
Manure Runoff Agriculture color.gif 3.6
Leaking Underground Storage Tanks Land Application/Waste Sites/Tanks color.gif 3.6
Erosion From Derelict Land (Barren Land) Hydromodification color.gif 3.1
Sources Outside State Jurisdiction Or Borders Other color.gif 2.9

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Site-specific Targeted Monitoring Results

Montana Lakes, Reservoirs, and Ponds 2012

Description of this table

All
Lakes, Reservoirs, and Ponds

844,802.0 Acres of Lakes, Reservoirs, and Ponds

Assessed 565,529.4
Unassessed 279,272.6
Total Acres 844,802.0







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Description of this table

Assessed
Lakes, Reservoirs, and Ponds

565,529.4 Acres of
Assessed Lakes, Reservoirs, and Ponds

Good 69,518.1
Threatened 6,035.8
Impaired 489,975.5
Total Acres Assessed 565,529.4







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Description of this table

Threatened and Impaired
Lakes, Reservoirs, and Ponds

496,011.3 Acres of
Threatened and Impaired
Lakes, Reservoirs, and Ponds

4,580.0
.0
9,901.8
481,529.5
Total Threatened and Impaired 496,011.3

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Site-specific Targeted Monitoring Results

Individual Designated Use Support
Montana Lakes, Reservoirs, and Ponds 2012

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

Description of this table
% Good
% Threatened
% Impaired
Agricultural 292,782.5 82.5 .0 17.5 color.gifcolor.gif
Aquatic Life 565,226.4 18.8 1.1 80.1 color.gifcolor.gifcolor.gif
Drinking Water 523,374.9 41.8 .0 58.2 color.gifcolor.gif
Primary Contact Recreation 547,906.1 88.5 .0 11.5 color.gifcolor.gif

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Site-specific Targeted Monitoring Results

Causes of Impairment
Montana Lakes, Reservoirs, and Ponds 2012

Description of this table
Mercury Mercury color.gif 386,748.0
Lead Metals (other than Mercury) color.gif 257,102.0
Phosphorus, Total Nutrients color.gif 137,476.3
Nitrogen, Total Nutrients color.gif 132,484.6
Sedimentation/Siltation Sediment color.gif 131,965.7
Polychlorinated Biphenyls (PCBs) Polychlorinated Biphenyls (PCBs) color.gif 125,601.0
Other Flow Regime Alterations Flow Alteration(s) color.gif 46,025.8
Selenium Metals (other than Mercury) color.gif 41,790.3
Excess Algal Growth Algal Growth color.gif 38,410.0
Arsenic Metals (other than Mercury) color.gif 37,609.0
Ammonia, Un-ionized Ammonia color.gif 32,810.0
Thallium Metals (other than Mercury) color.gif 32,810.0
Salinity Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 13,024.3
Sulfates Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 9,400.0
Physical Substrate Habitat Alterations Habitat Alterations color.gif 8,787.8
Cadmium Metals (other than Mercury) color.gif 8,599.0
Dissolved Oxygen Organic Enrichment/Oxygen Depletion color.gif 7,042.6
Total Dissolved Solids (TDS) Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 3,800.0
Other Anthropogenic Substrate Alterations Habitat Alterations color.gif 3,783.1
Chromium, Total Metals (other than Mercury) color.gif 3,780.8
Cause Unknown Cause Unknown color.gif 3,780.8
Low Flow Alterations Flow Alteration(s) color.gif 3,780.8
Chlorophyll-A Algal Growth color.gif 3,506.8
Solids (Suspended/Bedload) Sediment color.gif 3,500.0
Aquatic Plants - Native Nuisance Native Species color.gif 3,500.0
Endosulfan Sulfate Pesticides color.gif 3,190.0
DDT Pesticides color.gif 3,190.0
Endrin Aldehyde Pesticides color.gif 3,190.0
Nitrogen, Nitrate Nutrients color.gif 3,190.0
BOD, Sediment Load (Sediment Oxygen Demand) Organic Enrichment/Oxygen Depletion color.gif 2,680.0
Iron Metals (other than Mercury) color.gif 1,903.0
Copper Metals (other than Mercury) color.gif 1,903.0
Total Kjehldahl Nitrogen (TKN) Nutrients color.gif 352.6
Other Cause Other Cause color.gif 80.0
Alteration in Stream-Side or Littoral Vegetative Covers Habitat Alterations color.gif 9.0

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Site-specific Targeted Monitoring Results

Probable Sources
Montana Lakes, Reservoirs, and Ponds 2012

Description of this table
Impacts From Abandoned Mine Lands (Inactive) Resource Extraction color.gif 290,738.8
Atmospheric Deposition - Toxics Atmospheric Deposition color.gif 261,147.0
Historic Bottom Deposits (Not Sediment) Legacy/Historical Pollutants color.gif 249,358.0
Municipal Point Source Discharges Municipal Discharges/Sewage color.gif 163,352.0
Source Unknown Unknown color.gif 151,284.4
Impacts From Hydrostructure Flow Regulation/Modification Hydromodification color.gif 140,031.5
Atmospheric Deposition - Nitrogen Atmospheric Deposition color.gif 122,252.0
Unspecified Urban Stormwater Urban-Related Runoff/Stormwater color.gif 122,252.0
Upstream Impoundments (E.G., Pl-566 Nrcs Structures) Hydromodification color.gif 122,252.0
Silviculture Harvesting Silviculture (Forestry) color.gif 122,252.0
Agriculture Agriculture color.gif 55,940.9
Natural Sources Natural/Wildlife color.gif 43,283.8
Acid Mine Drainage Resource Extraction color.gif 41,380.8
On-Site Treatment Systems (Septic Systems And Similar Decentralized Systems) Municipal Discharges/Sewage color.gif 36,000.0
Site Clearance (Land Development Or Redevelopment) Construction color.gif 32,810.0
Internal Nutrient Recycling Natural/Wildlife color.gif 32,810.0
Dam Or Impoundment Hydromodification color.gif 32,388.0
Sources Outside State Jurisdiction Or Borders Other color.gif 28,888.0
Irrigated Crop Production Agriculture color.gif 26,789.7
Silviculture Activities Silviculture (Forestry) color.gif 6,545.8
Grazing In Riparian Or Shoreline Zones Agriculture color.gif 6,528.9
Forest Roads (Road Construction And Use) Silviculture (Forestry) color.gif 6,029.0
Rangeland Grazing Agriculture color.gif 4,932.1
Drought-Related Impacts Natural/Wildlife color.gif 4,888.0
Inappropriate Waste Disposal Spills/Dumping color.gif 4,358.0
Placer Mining Resource Extraction color.gif 4,358.0
Habitat Modification - Other Than Hydromodification Habitat Alterations (Not Directly Related To Hydromodification) color.gif 3,780.8
Upstream Source Other color.gif 3,332.1
Contaminated Sediments Legacy/Historical Pollutants color.gif 3,190.0
Mine Tailings Resource Extraction color.gif 3,190.0
Highway/Road/Bridge Runoff (Non-Construction Related) Urban-Related Runoff/Stormwater color.gif 3,190.0
Dam Construction (Other Than Upstream Flood Control Projects) Hydromodification color.gif 3,190.0
Highways, Roads, Bridges, Infrastructure (New Construction) Construction color.gif 2,691.3
Low Water Crossing Other color.gif 1,126.0
Upstream/Downstream Source Other color.gif 352.6
Petroleum/Natural Gas Activities Resource Extraction color.gif 9.0
Non-Irrigated Crop Production Agriculture color.gif 2.3

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Montana Causes of Impairment for Reporting Year 2012


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.
Size of Assessed Waters with Listed Causes of Impairment
Algal Growth 1,889.5 41,916.8
Ammonia 290.2 32,810.0
Cause Unknown 229.7 3,780.8
Cause Unknown - Impaired Biota 98.3
Flow Alteration(s) 6,531.6 49,806.6
Habitat Alterations 9,881.2 8,799.1
Mercury 1,867.6 386,748.0
Metals (other than Mercury) 5,626.2 338,682.1
Nuisance Exotic Species 11.0
Nuisance Native Species 13.0 3,500.0
Nutrients 7,113.9 143,076.3
Oil and Grease 114.0
Organic Enrichment/Oxygen Depletion 756.1 9,722.6
Other Cause 130.4 80.0
Pathogens 527.3
Pesticides 22.1 3,190.0
pH/Acidity/Caustic Conditions 353.6
Polychlorinated Biphenyls (PCBs) 72.1 125,601.0
Radiation 98.8
Salinity/Total Dissolved Solids/Chlorides/Sulfates 2,836.3 16,524.3
Sediment 8,302.8 135,465.7
Temperature 2,711.3
Toxic Inorganics 165.9
Toxic Organics 21.8
Turbidity 293.9

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Montana Probable Sources Contributing to Impairments
for Reporting Year 2012

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.
Size of Assessed Waters with Probable Sources of Impairments
Agriculture 12,494.2 69,832.9
Aquaculture 51.4
Atmospheric Deposition 91.5 383,399.0
Construction 1,637.4 35,501.3
Habitat Alterations (Not Directly Related To Hydromodification) 2,261.0 3,780.8
Hydromodification 7,249.7 172,419.5
Industrial 605.8
Land Application/Waste Sites/Tanks 3.6
Legacy/Historical Pollutants 289.9 252,548.0
Municipal Discharges/Sewage 904.5 163,352.0
Natural/Wildlife 4,665.0 48,171.8
Other 127.9 32,572.7
Recreation And Tourism (Non-Boating) 216.7
Resource Extraction 2,748.2 290,747.8
Silviculture (Forestry) 1,906.9 131,477.8
Spills/Dumping 255.8 4,358.0
Unknown 4,664.1 151,284.4
Urban-Related Runoff/Stormwater 1,447.8 125,442.0

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Montana TMDL Alternatives by Cause of Impairment 2012


No TMDL Alternatives reported.

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Montana 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.
2010 color.gif 1 1
2011 color.gif 2 2

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Montana 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.
Metals (other than Mercury) color.gif 548
Nutrients color.gif 443
Sediment color.gif 271
Mercury color.gif 74
Temperature color.gif 68
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 63
Organic Enrichment/Oxygen Depletion color.gif 20
pH/Acidity/Caustic Conditions color.gif 19
Pathogens color.gif 18
Turbidity color.gif 12
Ammonia color.gif 11
Toxic Inorganics color.gif 10
Cause Unknown - Impaired Biota color.gif 6
Polychlorinated Biphenyls (PCBs) color.gif 5
Oil and Grease color.gif 4
Pesticides color.gif 4
Other Cause color.gif 3
Radiation color.gif 2
Nuisance Exotic Species color.gif 1
Toxic Organics color.gif 1

Total: 1,583 Causes of Impairment

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Montana 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.
Number of Causes of
Impairment Addressed
Sediment color.gif 237 348
Lead color.gif 122 125
Copper color.gif 110 113
Cadmium color.gif 95 102
Arsenic color.gif 87 88
Zinc color.gif 86 88
Nitrogen, Total color.gif 68 75
Iron color.gif 67 68
Phosphorus, Total color.gif 65 69
Sedimentation/Siltation color.gif 58 60
Aluminum color.gif 42 42
Phosphorus color.gif 30 43
Temperature color.gif 30 36
Mercury color.gif 27 27
Nitrogen color.gif 21 29
Siltation color.gif 19 19
Selenium color.gif 13 13
Manganese color.gif 12 12
Thermal Modifications color.gif 10 10
Suspended Solids color.gif 9 9
Total Dissolved Solids (TDS) color.gif 9 17
Cyanide color.gif 8 8
Fecal Coliform color.gif 8 8
Antimony color.gif 7 7
Escherichia Coli (E. Coli) color.gif 7 7
Fecal color.gif 7 9
Nickel color.gif 7 7
Nitrite/Nitrate color.gif 7 7
Nitrate/Nitrite color.gif 6 6
Total Residual Chlorine color.gif 6 6
Total Suspended Solids (TSS) color.gif 6 7
Ammonia color.gif 5 5
Nitrate color.gif 4 4
Silver color.gif 4 4
Chromium, Total color.gif 3 3
Salinity color.gif 3 4
Tin color.gif 3 3
pH color.gif 3 3
Nitrates color.gif 2 2
Polychlorinated Biphenyls (PCBs) color.gif 2 2
Salinity/Total Dissolved Solids/Sulfates color.gif 2 2
Sulfates color.gif 2 2
Beryllium color.gif 1 1
Biochemical Oxygen Demand (BOD) color.gif 1 1
Fluoride color.gif 1 1
Noxious Aquatic Plants color.gif 1 1
Nutrients color.gif 1 3
Sulfate color.gif 1 1
Thallium color.gif 1 1
Total Toxics color.gif 1 1
Turbidity color.gif 1 1

Total: 1,328 TMDLs; 1,510 Causes of Impairment Addressed


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Montana 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.
1997 color.gif 10 10
1998 color.gif 32 37
1999