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On This Page 303(d) Listed Waters for 2006

Data are also available for these cycles:
2002 2004 2008 2010 2012

Waterbody Changes from Prior Cycle

For More Information:

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Montana Water Quality Assessment Report

Assessed Waters of Montana by Watershed

Select a watershed from the list:
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Search for a waterbody within Montana
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Display impaired waters and TMDL information only


NOTE: The data provided in this report differs slightly from the information provided in the original Montana 2006 305(b) report. This is a result of differences between the Montana State assessment database and the summary data provided in Montana's 2006 Integrated Report, which is available at http://www.deq.mt.gov/CWAIC/wqrep/2006/FINAL_2006_MT_IR.pdf.



Site-specific Targeted Monitoring Summary Results

Montana (2006)

Description of this table
 
    2,784.9 74,482.2
       144.9
    6,029.9
                2,680.0
                
                
                3,349.9
    15,221.0 499,020.1
           851.4     300.0
                
           1,731.3     37,738.0
           12,638.2     460,982.1
              1,491.7     1,620.0
                    11,146.5           459,362.1
18,005.9 579,532.2
176,750.0 844,802.0
10.2 68.6

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Summary of Water Quality Assessments for Each Waterbody Type
for Reporting Year 2006


Site-specific Targeted Monitoring Results

Montana Rivers and Streams 2006

Description of this table
Assessed 18,005.9
Unassessed 158,744.2
Total Miles 176,750.0







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Description of this table
Good 2,784.9
Threatened .0
Impaired 15,221.0
Total Miles Assessed 18,005.9







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Description of this table
2,343.1
.0
1,731.3
11,146.5
Total Threatened and Impaired 15,221.0

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Site-specific Targeted Monitoring Results

Individual Designated Use Support
Montana Rivers and Streams 2006

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

Description of this table
% Good
% Threatened
% Impaired
Agricultural 12,452.9 89.3 .0 10.7 color.gifcolor.gif
Aquatic Life 16,924.8 18.6 .0 81.4 color.gifcolor.gif
Cold Water Fishery 10,249.1 16.1 .0 83.9 color.gifcolor.gif
Drinking Water 11,196.6 69.3 .1 30.6 color.gifcolor.gifcolor.gif
Industrial 12,601.5 89.1 .0 10.9 color.gifcolor.gif
Primary Contact Recreation 14,806.0 60.9 1.0 38.1 color.gifcolor.gifcolor.gif
Warm Water Fishery 6,485.9 17.7 .0 82.3 color.gifcolor.gif

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Site-specific Targeted Monitoring Results

Causes of Impairment
Montana Rivers and Streams 2006

Description of this table
Alteration in Stream-Side or Littoral Vegetative Covers Habitat Alterations color.gif 7,683.9
Sedimentation/Siltation Sediment color.gif 6,368.4
Phosphorus, Total Nutrients color.gif 4,590.1
Low Flow Alterations Flow Alteration(s) color.gif 4,251.4
Physical Substrate Habitat Alterations Habitat Alterations color.gif 3,271.3
Lead Metals (other than Mercury) color.gif 3,027.1
Copper Metals (other than Mercury) color.gif 2,809.8
Total Kjehldahl Nitrogen (TKN) Nutrients color.gif 2,729.2
Temperature, Water Temperature color.gif 2,393.1
Nitrate/Nitrite (Nitrite + Nitrate as N) Nutrients color.gif 2,065.4
Mercury Mercury color.gif 1,761.4
Iron Metals (other than Mercury) color.gif 1,713.9
Nitrogen, Total Nutrients color.gif 1,713.6
Zinc Metals (other than Mercury) color.gif 1,582.6
Cadmium Metals (other than Mercury) color.gif 1,517.7
Chlorophyll-A Algal Growth color.gif 1,475.0
Arsenic Metals (other than Mercury) color.gif 1,391.2
Other Flow Regime Alterations Flow Alteration(s) color.gif 1,272.4
Total Dissolved Solids (TDS) Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 1,177.0
Solids (Suspended/Bedload) Sediment color.gif 983.2
Salinity Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 766.1
Sulfates Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 595.1
Fish Passage Barrier Habitat Alterations color.gif 542.0
Dissolved Oxygen Organic Enrichment/Oxygen Depletion color.gif 447.8
Fecal Coliform Pathogens color.gif 433.6
Specific Conductivity Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 391.7
Other Anthropogenic Substrate Alterations Habitat Alterations color.gif 373.2
pH pH/Acidity/Caustic Conditions color.gif 343.9
Selenium Metals (other than Mercury) color.gif 321.4
Excess Algal Growth Algal Growth color.gif 307.8
Nitrates Nutrients color.gif 306.5
Chromium, Total Metals (other than Mercury) color.gif 300.7
Aluminum Metals (other than Mercury) color.gif 289.7
Cause Unknown Cause Unknown color.gif 249.0
Ammonia, Un-ionized Ammonia color.gif 227.9
Nitrogen, Nitrate Nutrients color.gif 222.8
Organic Enrichment (Sewage) Biological Indicators Organic Enrichment/Oxygen Depletion color.gif 181.5
Nickel Metals (other than Mercury) color.gif 167.2
Turbidity Turbidity color.gif 166.8
Manganese Metals (other than Mercury) color.gif 142.5
High Flow Regime Flow Alteration(s) color.gif 141.7
Silver Metals (other than Mercury) color.gif 140.6
Total Suspended Solids (TSS) Turbidity color.gif 124.0
Alterations in Wetland Habitats Habitat Alterations color.gif 108.0
Other Cause Other Cause color.gif 105.8
Habitat Assessment (Streams) Cause Unknown - Impaired Biota color.gif 86.7
Uranium Radiation color.gif 81.3
Escherichia Coli (E. Coli) Pathogens color.gif 75.1
Antimony Toxic Inorganics color.gif 72.5
Cyanide Toxic Inorganics color.gif 72.1
Benthic Macroinvertebrates Bioassessments Cause Unknown - Impaired Biota color.gif 64.5
Ammonia, Total Ammonia color.gif 62.5
Polychlorinated Biphenyls (PCBs) Polychlorinated Biphenyls (PCBs) color.gif 54.3
Biochemical Oxygen Demand (BOD) Organic Enrichment/Oxygen Depletion color.gif 51.3
Sodium Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 36.6
Bottom Deposits Sediment color.gif 28.8
Nutrient/Eutrophication Biological Indicators Nutrients color.gif 25.7
Oil and Grease Oil and Grease color.gif 23.7
DDE Pesticides color.gif 21.6
Polycyclic Aromatic Hydrocarbons (PAHs) (Aquatic Ecosystems) Toxic Organics color.gif 18.4
Mercury in Water Column Mercury color.gif 18.2
Pentachlorobenzene Toxic Organics color.gif 17.8
Chloride Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 16.4
Combined Biota/Habitat Bioassessments (Streams) Cause Unknown - Impaired Biota color.gif 12.1
Aquatic Plants - Native Nuisance Native Species color.gif 11.1
Barium Radiation color.gif 11.0
Cobalt Metals (other than Mercury) color.gif 11.0
Phosphate Nutrients color.gif 10.4
Non-Native Fish/Shellfish/Zooplankton Nuisance Exotic Species color.gif 9.8
Thallium Metals (other than Mercury) color.gif 5.4
Beryllium Metals (other than Mercury) color.gif 4.9
Dissolved Gas Supersaturation Other Cause color.gif 2.8

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Site-specific Targeted Monitoring Results

Probable Sources
Montana Rivers and Streams 2006

Description of this table
Agriculture Agriculture color.gif 5,203.6
Grazing In Riparian Or Shoreline Zones Agriculture color.gif 5,125.0
Source Unknown Unknown color.gif 4,017.1
Irrigated Crop Production Agriculture color.gif 3,831.8
Natural Sources Natural/Wildlife color.gif 3,278.5
Streambank Modifications/Destablization Hydromodification color.gif 2,307.8
Rangeland Grazing Agriculture color.gif 2,085.8
Impacts From Hydrostructure Flow Regulation/Modification Hydromodification color.gif 2,058.0
Impacts From Abandoned Mine Lands (Inactive) Resource Extraction color.gif 1,867.2
Channelization Hydromodification color.gif 1,798.8
Loss Of Riparian Habitat Habitat Alterations (Not Directly Related To Hydromodification) color.gif 1,713.2
Flow Alterations From Water Diversions Hydromodification color.gif 1,374.1
Dam Or Impoundment Hydromodification color.gif 1,282.5
Highways, Roads, Bridges, Infrasturcture (New Construction) Construction color.gif 1,049.8
Forest Roads (Road Construction And Use) Silviculture (Forestry) color.gif 958.6
Silviculture Activities Silviculture (Forestry) color.gif 877.8
Municipal Point Source Discharges Municipal Discharges/Sewage color.gif 735.3
Highway/Road/Bridge Runoff (Non-Construction Related) Urban-Related Runoff/Stormwater color.gif 663.4
Acid Mine Drainage Resource Extraction color.gif 648.6
Non-Irrigated Crop Production Agriculture color.gif 642.2
Crop Production (Crop Land Or Dry Land) Agriculture color.gif 579.1
Dam Construction (Other Than Upstream Flood Control Projects) Hydromodification color.gif 556.8
Unspecified Unpaved Road Or Trail Urban-Related Runoff/Stormwater color.gif 541.9
Mine Tailings Resource Extraction color.gif 493.4
Silviculture Harvesting Silviculture (Forestry) color.gif 473.4
Habitat Modification - Other Than Hydromodification Habitat Alterations (Not Directly Related To Hydromodification) color.gif 467.7
Site Clearance (Land Development Or Redevelopment) Construction color.gif 464.9
Animal Feeding Operations (Nps) Agriculture color.gif 404.9
Mill Tailings Industrial color.gif 391.1
Contaminated Sediments Legacy/Historical Pollutants color.gif 289.2
Placer Mining Resource Extraction color.gif 263.7
Subsurface (Hardrock) Minining Resource Extraction color.gif 263.3
Industrial Point Source Discharge Industrial color.gif 248.8
Transfer Of Water From An Outside Watershed Hydromodification color.gif 179.7
Dredge Mining Resource Extraction color.gif 138.5
Upstream Impoundments (E.G., Pl-566 Nrcs Structures) Hydromodification color.gif 128.6
Surface Mining Resource Extraction color.gif 127.8
Livestock (Grazing Or Feeding Operations) Agriculture color.gif 125.3
Hydrostructure Impacts On Fish Passage Hydromodification color.gif 124.8
Post-Development Erosion And Sedimentation Hydromodification color.gif 116.2
Residential Districts Urban-Related Runoff/Stormwater color.gif 111.5
Drought-Related Impacts Natural/Wildlife color.gif 108.6
Above Ground Storage Tank Leaks (Tank Farms) Spills/Dumping color.gif 105.0
On-Site Treatment Systems (Septic Systems And Similar Decencentralized Systems) Municipal Discharges/Sewage color.gif 96.6
Golf Courses Recreation And Tourism (Non-Boating) color.gif 94.7
Impacts From Resort Areas (Winter And Non-Winter Resorts) Recreation And Tourism (Non-Boating) color.gif 92.6
Watershed Runoff Following Forest Fire Silviculture (Forestry) color.gif 90.0
Managed Pasture Grazing Agriculture color.gif 89.8
Wet Weather Discharges (Point Source And Combination Of Stormwater, Sso Or Cso) Municipal Discharges/Sewage color.gif 83.6
Upstream Source Other color.gif 73.4
Coal Mining Resource Extraction color.gif 62.3
Permitted Runoff From Confined Animal Feeding Operations (Cafos) Agriculture color.gif 51.3
Aquaculture (Permitted) Aquaculture color.gif 50.1
Channel Erosion/Incision From Upstream Hydromodifications Hydromodification color.gif 49.3
Low Water Crossing Other color.gif 47.2
Crop Production With Subsurface Drainage Agriculture color.gif 44.5
Atmospheric Deposition - Nitrogen Atmospheric Deposition color.gif 37.1
Hardrock Mining Discharges (Permitted) Resource Extraction color.gif 35.9
Atmospheric Deposition - Toxics Atmospheric Deposition color.gif 33.6
Sediment Resuspension (Clean Sediment) Hydromodification color.gif 31.1
Unspecified Urban Stormwater Urban-Related Runoff/Stormwater color.gif 28.7
Yard Maintenance Urban-Related Runoff/Stormwater color.gif 26.3
Spills From Trucks Or Trains Spills/Dumping color.gif 26.0
Sediment Resuspension (Contaminated Sediment) Hydromodification color.gif 23.4
Other Recreational Pollution Sources Recreation And Tourism (Non-Boating) color.gif 21.3
Petroleum/Natural Gas Production Activities (Permitted) Industrial color.gif 18.4
Pipeline Breaks Spills/Dumping color.gif 18.4
Wet Weather Discharges (Non-Point Source) Urban-Related Runoff/Stormwater color.gif 14.7
Construction Stormwater Discharge (Permitted) Construction color.gif 14.0
Discharges From Municipal Separate Storm Sewer Systems (Ms4) Urban-Related Runoff/Stormwater color.gif 11.8
Freshettes Or Major Flooding Natural/Wildlife color.gif 11.2
Septage Disposal Municipal Discharges/Sewage color.gif 9.2
Industrial/Commercial Site Stormwater Discharge (Permittted) Urban-Related Runoff/Stormwater color.gif 7.6
Open Pit Mining Resource Extraction color.gif 7.4
Municipal (Urbanized High Density Area) Urban-Related Runoff/Stormwater color.gif 7.0
Baseflow Depletion From Groundwater Withdrawals Hydromodification color.gif 4.5
Heap-Leach Extraction Mining Resource Extraction color.gif 4.1
Sources Outside State Juristiction Or Borders Other color.gif 2.8
Erosion From Derelict Land (Barren Land) Hydromodification color.gif 1.8

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Site-specific Targeted Monitoring Results

Montana Lakes, Reservoirs, and Ponds 2006

Description of this table
Assessed 579,532.2
Unassessed 265,269.8
Total Acres 844,802.0







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Description of this table
Good 74,482.2
Threatened 6,029.9
Impaired 499,020.1
Total Acres Assessed 579,532.2







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Description of this table
4,600.0
.0
37,738.0
462,712.0
Total Threatened and Impaired 505,050.0

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Site-specific Targeted Monitoring Results

Individual Designated Use Support
Montana Lakes, Reservoirs, and Ponds 2006

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

Description of this table
% Good
% Threatened
% Impaired
Agricultural 308,533.3 82.4 .0 17.6 color.gifcolor.gif
Aquatic Life 334,229.2 34.4 1.8 63.8 color.gifcolor.gifcolor.gif
Cold Water Fishery 274,624.4 80.0 2.2 17.8 color.gifcolor.gifcolor.gif
Drinking Water 531,928.6 42.7 .0 57.3 color.gifcolor.gif
Industrial 312,638.0 97.6 .0 2.4 color.gifcolor.gif
Primary Contact Recreation 567,343.2 44.2 .0 55.8 color.gifcolor.gif
Warm Water Fishery 51,920.8 50.0 .0 50.0 color.gifcolor.gif

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Site-specific Targeted Monitoring Results

Causes of Impairment
Montana Lakes, Reservoirs, and Ponds 2006

Description of this table
Mercury Mercury color.gif 392,275.8
Lead Metals (other than Mercury) color.gif 257,122.0
Aquatic Plants - Native Nuisance Native Species color.gif 248,500.0
Sedimentation/Siltation Sediment color.gif 135,721.5
Phosphorus, Total Nutrients color.gif 135,361.2
Nitrogen, Total Nutrients color.gif 133,206.9
Polychlorinated Biphenyls (PCBs) Polychlorinated Biphenyls (PCBs) color.gif 129,356.8
Other Flow Regime Alterations Flow Alteration(s) color.gif 44,980.8
Excess Algal Growth Algal Growth color.gif 40,780.0
Arsenic Metals (other than Mercury) color.gif 36,809.0
Ammonia, Un-ionized Ammonia color.gif 35,180.0
Thallium Metals (other than Mercury) color.gif 35,180.0
Salinity Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 13,697.0
Selenium Metals (other than Mercury) color.gif 13,575.0
Sulfates Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 9,400.0
Cadmium Metals (other than Mercury) color.gif 8,619.0
Physical Substrate Habitat Alterations Habitat Alterations color.gif 7,780.8
Chlorophyll-A Algal Growth color.gif 6,620.0
Other Anthropogenic Substrate Alterations Habitat Alterations color.gif 4,455.8
Dissolved Oxygen Organic Enrichment/Oxygen Depletion color.gif 4,152.6
Total Dissolved Solids (TDS) Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 3,800.0
DDT Pesticides color.gif 3,800.0
Endrin Aldehyde Pesticides color.gif 3,800.0
Endosulfan Pesticides color.gif 3,800.0
Cause Unknown Cause Unknown color.gif 3,780.8
Low Flow Alterations Flow Alteration(s) color.gif 3,780.8
Chromium, Total Metals (other than Mercury) color.gif 3,780.8
BOD, Sediment Load (Sediment Oxygen Demand) Organic Enrichment/Oxygen Depletion color.gif 2,680.0
Copper Metals (other than Mercury) color.gif 1,923.0
Iron Metals (other than Mercury) color.gif 1,903.0
Total Suspended Solids (TSS) Turbidity color.gif 1,600.0
Temperature, Water Temperature color.gif 1,600.0
Total Kjehldahl Nitrogen (TKN) Nutrients color.gif 352.6
Other Cause Other Cause color.gif 80.0
Zinc Metals (other than Mercury) color.gif 20.0
pH pH/Acidity/Caustic Conditions color.gif 20.0
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 2006

Description of this table
Agriculture Agriculture color.gif 308,934.1
Impacts From Abandoned Mine Lands (Inactive) Resource Extraction color.gif 291,080.8
Atmospheric Deposition - Toxics Atmospheric Deposition color.gif 259,099.0
Historic Bottom Deposits (Not Sediment) Legacy/Historical Pollutants color.gif 250,500.0
Municipal Point Source Discharges Municipal Discharges/Sewage color.gif 164,686.9
Source Unknown Unknown color.gif 156,792.2
Impacts From Hydrostructure Flow Regulation/Modification Hydromodification color.gif 143,389.4
Unspecified Urban Stormwater Urban-Related Runoff/Stormwater color.gif 126,006.9
Atmospheric Deposition - Nitrogen Atmospheric Deposition color.gif 126,006.9
Upstream Impoundments (E.G., Pl-566 Nrcs Structures) Hydromodification color.gif 126,006.9
Silviculture Harvesting Silviculture (Forestry) color.gif 126,006.9
Natural Sources Natural/Wildlife color.gif 46,263.8
Acid Mine Drainage Resource Extraction color.gif 40,560.8
Internal Nutrient Recycling Natural/Wildlife color.gif 35,180.0
On-Site Treatment Systems (Septic Systems And Similar Decencentralized Systems) Municipal Discharges/Sewage color.gif 35,180.0
Site Clearance (Land Development Or Redevelopment) Construction color.gif 35,180.0
Dam Or Impoundment Hydromodification color.gif 32,350.0
Irrigated Crop Production Agriculture color.gif 23,289.7
Silviculture Activities Silviculture (Forestry) color.gif 8,669.9
Forest Roads (Road Construction And Use) Silviculture (Forestry) color.gif 6,029.9
Inappropriate Waste Disposal Spills/Dumping color.gif 5,500.0
Placer Mining Resource Extraction color.gif 5,500.0
Drought-Related Impacts Natural/Wildlife color.gif 4,888.0
Grazing In Riparian Or Shoreline Zones Agriculture color.gif 4,852.1
Highway/Road/Bridge Runoff (Non-Construction Related) Urban-Related Runoff/Stormwater color.gif 3,800.0
Habitat Modification - Other Than Hydromodification Habitat Alterations (Not Directly Related To Hydromodification) color.gif 3,780.8
Highways, Roads, Bridges, Infrasturcture (New Construction) Construction color.gif 3,364.0
Rangeland Grazing Agriculture color.gif 3,332.1
Upstream Source Other color.gif 3,332.1
Low Water Crossing Other color.gif 1,126.0
Non-Irrigated Crop Production Agriculture color.gif 675.0
Upstream/Dowstream Source Other color.gif 352.6
Petroleum/Natural Gas Activities Resource Extraction color.gif 9.0

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Montana Causes of Impairment for Reporting Year 2006


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 1,782.8 47,400.0
Ammonia 290.4 35,180.0
Cause Unknown 249.0 3,780.8
Cause Unknown - Impaired Biota 163.3
Flow Alteration(s) 5,647.5 48,761.6
Habitat Alterations 9,135.1 8,464.8
Mercury 1,779.6 392,275.8
Metals (other than Mercury) 4,978.8 309,666.8
Nuisance Exotic Species 9.8
Nuisance Native Species 11.1 248,500.0
Nutrients 6,594.5 140,961.2
Oil and Grease 23.7
Organic Enrichment/Oxygen Depletion 680.6 6,832.6
Other Cause 108.6 80.0
Pathogens 508.7
Pesticides 21.6 3,800.0
pH/Acidity/Caustic Conditions 343.9 20.0
Polychlorinated Biphenyls (PCBs) 54.3 129,356.8
Radiation 92.3
Salinity/Total Dissolved Solids/Chlorides/Sulfates 1,795.3 17,197.0
Sediment 7,013.6 135,721.5
Temperature 2,393.1 1,600.0
Toxic Inorganics 140.5
Toxic Organics 36.2
Turbidity 290.8 1,600.0

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Montana Probable Sources Contributing to Impairments
for Reporting Year 2006

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 10,992.4 319,998.8
Aquaculture 50.1
Atmospheric Deposition 70.7 385,105.9
Construction 1,494.7 38,544.0
Habitat Alterations (Not Directly Related To Hydromodification) 2,074.9 3,780.8
Hydromodification 6,721.4 175,739.4
Industrial 599.4
Legacy/Historical Pollutants 289.2 250,500.0
Municipal Discharges/Sewage 886.6 164,686.9
Natural/Wildlife 3,398.3 51,151.8
Other 120.6 3,684.7
Recreation And Tourism (Non-Boating) 208.6
Resource Extraction 2,570.3 291,089.8
Silviculture (Forestry) 1,838.3 137,356.8
Spills/Dumping 149.4 5,500.0
Unknown 4,017.1 156,792.2
Urban-Related Runoff/Stormwater 1,374.5 129,806.9

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Montana TMDL Alternatives by Cause of Impairment 2006


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 691
Nutrients color.gif 513
Sediment color.gif 380
Algal Growth color.gif 100
Temperature color.gif 89
Mercury color.gif 72
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 60
Turbidity color.gif 57
Organic Enrichment/Oxygen Depletion color.gif 21
Pathogens color.gif 17
pH/Acidity/Caustic Conditions color.gif 16
Toxic Inorganics color.gif 13
Ammonia color.gif 11
Cause Unknown color.gif 11
Cause Unknown - Impaired Biota color.gif 5
Pesticides color.gif 4
Toxic Organics color.gif 3
Other Cause color.gif 3
Polychlorinated Biphenyls (PCBs) color.gif 3
Habitat Alterations color.gif 3
Nuisance Native Species color.gif 2
Radiation color.gif 2
Nuisance Exotic Species color.gif 1
Oil and Grease color.gif 1

Total: 2,078 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 203 303
Lead color.gif 105 107
Copper color.gif 96 98
Cadmium color.gif 83 91
Zinc color.gif 73 76
Arsenic color.gif 72 74
Sedimentation/Siltation color.gif 58 61
Iron color.gif 54 55
Nitrogen, Total color.gif 45 49
Phosphorus, Total color.gif 35 40
Phosphorus color.gif 30 43
Aluminum color.gif 25 25
Temperature color.gif 25 31
Nitrogen color.gif 21 29
Mercury color.gif 20 20
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
Fecal Coliform color.gif 8 8
Cyanide 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 6 6
Total Residual Chlorine color.gif 6 6
Total Suspended Solids (TSS) color.gif 6 7
Ammonia color.gif 5 5
Antimony color.gif 5 6
Chromium, Total color.gif 3 3
Salinity color.gif 3 4
Silver color.gif 3 3
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
Beryllium color.gif 1 1
Biochemical Oxygen Demand (BOD) color.gif 1 1
Fluoride color.gif 1 1
Nitrate color.gif 1 1
Nitrate/Nitrite color.gif 1 1
Noxious Aquatic Plants color.gif 1 1
Nutrients color.gif 1 3
Sulfate color.gif 1 1
Sulfates color.gif 1 1
Thallium color.gif 1 1
Total Toxics color.gif 1 1
Turbidity color.gif 1 1

Total: 1,114 TMDLs; 1,286 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 color.gif 18 33
2001 color.gif 1 1
2002 color.gif 16 20
2003 color.gif 46 49
2004 color.gif 56 75
2005 color.gif 67 73
2006 color.gif 124 127
2007 color.gif 34 36
2008 color.gif 88 117
2009 color.gif 119 122
2010 color.gif 98 99
2011 color.gif 98 113
2012 color.gif 143 200
2013 color.gif 164 174

Total: 1,114 TMDLs; 1,286 Causes of Impairment Addressed

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