Montana Water Quality Assessment Report

Assessed Waters of Montana by Watershed

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NOTE: On December 22, 2009, EPA approved the Montana Department of Environmental Quality (DEQ) 2008's 303(d) list and took no action on waters listed as impaired for salinity in the Tongue and Powder River watersheds. In the 2008 303(d) list, the State listed several waterbodies in the Tongue and Powder River watersheds as impaired for salinity based on an interpretation of the State's electrical conductivity (EC) and sodium adsorption ratio (SAR) criteria. The October 13, 2009 decision by the United States District Court for the District of Wyoming in the Pennaco Energy Inc v. U.S. Environmental Protection Agency (D. Wyo. 06-CV-100-B) vacated EPA’s approval of Montana’s water quality standards for EC and SAR, which means these criteria are no longer effective for Clean Water Act purposes. Those waters in the Tongue and Powder River watersheds that were on the Montana 2008 303(d) list based on an EC and SAR exceedance were excluded from EPA review and approval.

	Rivers and Streams (Miles)	Lakes, Reservoirs, and Ponds (Acres)
	Size of Water
Good Waters	2,816.6	74,482.2
Previously impaired waters now attaining all uses	144.9
Threatened Waters		6,029.9
TMDL completed		2,680.0
TMDL alternative
Non-pollutant impairment
TMDL needed		3,349.9
Impaired Waters	16,156.7	499,020.1
TMDL completed	962.0	1,900.0
TMDL alternative
Non-pollutant impairment	1,854.0	39,258.0
TMDL needed	13,340.7	457,862.1
New TMDLs completed	1,367.8	20.0
Remaining TMDLs needed	11,972.9	457,842.1

Total Assessed Waters	18,973.3	579,532.2
Total Waters	176,750.0	844,802.0
Percent of Waters Assessed	10.7	68.6

Designated Use	Miles Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
					% Threatened
					% Impaired
Agricultural	13,442.3	84.1	.0	15.9
Aquatic Life	17,432.3	18.1	.0	81.9
Cold Water Fishery	10,280.7	16.3	.0	83.7
Drinking Water	11,408.3	69.6	.0	30.4
Industrial	12,798.9	89.1	.0	10.9
Primary Contact Recreation	14,789.3	61.2	.9	37.9
Warm Water Fishery	6,951.9	16.5	.0	83.5

Cause of Impairment	Cause of Impairment Group	Miles Threatened or Impaired
Alteration in Stream-Side or Littoral Vegetative Covers	Habitat Alterations	7,764.4
Sedimentation/Siltation	Sediment	6,356.2
Low Flow Alterations	Flow Alteration(s)	4,648.7
Phosphorus, Total	Nutrients	4,603.9
Physical Substrate Habitat Alterations	Habitat Alterations	3,258.4
Lead	Metals (other than Mercury)	3,049.2
Copper	Metals (other than Mercury)	2,813.1
Total Kjehldahl Nitrogen (TKN)	Nutrients	2,731.8
Temperature, Water	Temperature	2,454.4
Nitrate/Nitrite (Nitrite + Nitrate as N)	Nutrients	2,065.4
Iron	Metals (other than Mercury)	2,010.7
Mercury	Mercury	1,761.4
Nitrogen, Total	Nutrients	1,707.6
Zinc	Metals (other than Mercury)	1,604.7
Salinity	Salinity/Total Dissolved Solids/Chlorides/Sulfates	1,578.5
Cadmium	Metals (other than Mercury)	1,539.8
Chlorophyll-A	Algal Growth	1,446.2
Arsenic	Metals (other than Mercury)	1,404.4
Other Flow Regime Alterations	Flow Alteration(s)	1,272.8
Solids (Suspended/Bedload)	Sediment	1,248.0
Total Dissolved Solids (TDS)	Salinity/Total Dissolved Solids/Chlorides/Sulfates	1,177.0
Sulfates	Salinity/Total Dissolved Solids/Chlorides/Sulfates	615.5
Fish Passage Barrier	Habitat Alterations	532.0
Dissolved Oxygen	Organic Enrichment/Oxygen Depletion	447.8
Fecal Coliform	Pathogens	430.8
Specific Conductivity	Salinity/Total Dissolved Solids/Chlorides/Sulfates	391.7
Other Anthropogenic Substrate Alterations	Habitat Alterations	373.6
pH	pH/Acidity/Caustic Conditions	351.1
Excess Algal Growth	Algal Growth	342.0
Selenium	Metals (other than Mercury)	323.1
Nitrates	Nutrients	303.7
Chromium, Total	Metals (other than Mercury)	300.7
Aluminum	Metals (other than Mercury)	291.4
Cause Unknown	Cause Unknown	249.0
Ammonia, Un-ionized	Ammonia	227.9
Nitrogen, Nitrate	Nutrients	222.8
Nickel	Metals (other than Mercury)	189.3
Organic Enrichment (Sewage) Biological Indicators	Organic Enrichment/Oxygen Depletion	181.5
Turbidity	Turbidity	155.9
Manganese	Metals (other than Mercury)	142.5
High Flow Regime	Flow Alteration(s)	141.7
Silver	Metals (other than Mercury)	140.6
Total Suspended Solids (TSS)	Turbidity	124.0
Alterations in Wetland Habitats	Habitat Alterations	108.0
Other Cause	Other Cause	105.8
Uranium	Radiation	81.3
Benthic Macroinvertebrates Bioassessments	Cause Unknown - Impaired Biota	76.0
Escherichia Coli (E. Coli)	Pathogens	75.1
Cyanide	Toxic Inorganics	73.8
Antimony	Toxic Inorganics	72.5
Ammonia, Total	Ammonia	62.5
Biochemical Oxygen Demand (BOD)	Organic Enrichment/Oxygen Depletion	51.3
Nutrient/Eutrophication Biological Indicators	Nutrients	37.2
Sodium	Salinity/Total Dissolved Solids/Chlorides/Sulfates	36.6
Polychlorinated Biphenyls (PCBs)	Polychlorinated Biphenyls (PCBs)	30.6
Bottom Deposits	Sediment	28.8
Oil and Grease	Oil and Grease	23.7
PCB in Water Column	Polychlorinated Biphenyls (PCBs)	23.7
DDE	Pesticides	21.6
Polycyclic Aromatic Hydrocarbons (PAHs) (Aquatic Ecosystems)	Toxic Organics	18.4
Mercury in Water Column	Mercury	18.2
Pentachlorobenzene	Toxic Organics	17.8
Chloride	Salinity/Total Dissolved Solids/Chlorides/Sulfates	16.4
Combined Biota/Habitat Bioassessments (Streams)	Cause Unknown - Impaired Biota	12.1
Periphyton (Aufwuchs) Indicator Bioassessments (Streams)	Cause Unknown - Impaired Biota	11.5
Dissolved Oxygen Saturation	Organic Enrichment/Oxygen Depletion	11.5
Aquatic Plants - Native	Nuisance Native Species	11.1
Cobalt	Metals (other than Mercury)	11.0
Barium	Radiation	11.0
Non-Native Fish/Shellfish/Zooplankton	Nuisance Exotic Species	9.8
Phosphate	Nutrients	8.3
Thallium	Metals (other than Mercury)	7.1
Beryllium	Metals (other than Mercury)	4.9
Dissolved Gas Supersaturation	Other Cause	2.8

Probable Source	Probable Source Group	Miles Threatened or Impaired
Agriculture	Agriculture	5,316.3
Grazing In Riparian Or Shoreline Zones	Agriculture	5,231.1
Source Unknown	Unknown	4,294.8
Irrigated Crop Production	Agriculture	4,267.0
Natural Sources	Natural/Wildlife	4,232.6
Streambank Modifications/Destabilization	Hydromodification	2,506.8
Impacts From Hydrostructure Flow Regulation/Modification	Hydromodification	2,242.2
Rangeland Grazing	Agriculture	2,103.6
Impacts From Abandoned Mine Lands (Inactive)	Resource Extraction	1,868.9
Channelization	Hydromodification	1,799.2
Loss Of Riparian Habitat	Habitat Alterations (Not Directly Related To Hydromodification)	1,709.9
Flow Alterations From Water Diversions	Hydromodification	1,374.1
Dam Or Impoundment	Hydromodification	1,282.5
Highways, Roads, Bridges, Infrastructure (New Construction)	Construction	1,153.8
Forest Roads (Road Construction And Use)	Silviculture (Forestry)	955.3
Silviculture Activities	Silviculture (Forestry)	857.1
Municipal Point Source Discharges	Municipal Discharges/Sewage	752.3
Highway/Road/Bridge Runoff (Non-Construction Related)	Urban-Related Runoff/Stormwater	654.9
Acid Mine Drainage	Resource Extraction	648.6
Non-Irrigated Crop Production	Agriculture	642.2
Crop Production (Crop Land Or Dry Land)	Agriculture	579.1
Site Clearance (Land Development Or Redevelopment)	Construction	568.5
Dam Construction (Other Than Upstream Flood Control Projects)	Hydromodification	546.8
Unspecified Unpaved Road Or Trail	Urban-Related Runoff/Stormwater	541.2
Mine Tailings	Resource Extraction	493.4
Silviculture Harvesting	Silviculture (Forestry)	476.0
Habitat Modification - Other Than Hydromodification	Habitat Alterations (Not Directly Related To Hydromodification)	467.7
Animal Feeding Operations (Nps)	Agriculture	404.9
Mill Tailings	Industrial	391.1
Contaminated Sediments	Legacy/Historical Pollutants	289.2
Placer Mining	Resource Extraction	263.7
Subsurface (Hardrock) Mining	Resource Extraction	263.3
Industrial Point Source Discharge	Industrial	248.8
Transfer Of Water From An Outside Watershed	Hydromodification	179.7
Dredge Mining	Resource Extraction	135.2
Upstream Impoundments (E.G., Pl-566 Nrcs Structures)	Hydromodification	128.6
Surface Mining	Resource Extraction	127.8
Livestock (Grazing Or Feeding Operations)	Agriculture	125.3
Hydrostructure Impacts On Fish Passage	Hydromodification	124.8
Post-Development Erosion And Sedimentation	Hydromodification	116.2
Residential Districts	Urban-Related Runoff/Stormwater	111.8
Drought-Related Impacts	Natural/Wildlife	108.6
Above Ground Storage Tank Leaks (Tank Farms)	Spills/Dumping	105.0
On-Site Treatment Systems (Septic Systems And Similar Decentralized Systems)	Municipal Discharges/Sewage	96.6
Golf Courses	Recreation And Tourism (Non-Boating)	94.7
Impacts From Resort Areas (Winter And Non-Winter Resorts)	Recreation And Tourism (Non-Boating)	92.6
Watershed Runoff Following Forest Fire	Silviculture (Forestry)	90.0
Managed Pasture Grazing	Agriculture	89.8
Wet Weather Discharges (Point Source And Combination Of Stormwater, Sso Or Cso)	Municipal Discharges/Sewage	83.6
Upstream Source	Other	73.4
Coal Mining	Resource Extraction	62.3
Permitted Runoff From Confined Animal Feeding Operations (Cafos)	Agriculture	51.3
Aquaculture (Permitted)	Aquaculture	50.1
Channel Erosion/Incision From Upstream Hydromodifications	Hydromodification	49.3
Low Water Crossing	Other	47.2
Crop Production With Subsurface Drainage	Agriculture	44.5
Yard Maintenance	Urban-Related Runoff/Stormwater	37.5
Atmospheric Deposition - Nitrogen	Atmospheric Deposition	37.1
Hardrock Mining Discharges (Permitted)	Resource Extraction	35.9
Atmospheric Deposition - Toxics	Atmospheric Deposition	33.6
Sediment Resuspension (Clean Sediment)	Hydromodification	31.1
Unspecified Urban Stormwater	Urban-Related Runoff/Stormwater	28.7
Spills From Trucks Or Trains	Spills/Dumping	26.0
Sediment Resuspension (Contaminated Sediment)	Hydromodification	23.4
Other Recreational Pollution Sources	Recreation And Tourism (Non-Boating)	21.3
Petroleum/Natural Gas Production Activities (Permitted)	Industrial	18.4
Pipeline Breaks	Spills/Dumping	18.4
Wet Weather Discharges (Non-Point Source)	Urban-Related Runoff/Stormwater	14.7
Construction Stormwater Discharge (Permitted)	Construction	14.0
Discharges From Municipal Separate Storm Sewer Systems (Ms4)	Urban-Related Runoff/Stormwater	11.8
Freshettes Or Major Flooding	Natural/Wildlife	11.2
Septage Disposal	Municipal Discharges/Sewage	9.2
Open Pit Mining	Resource Extraction	9.1
Industrial/Commercial Site Stormwater Discharge (Permitted)	Urban-Related Runoff/Stormwater	7.6
Municipal (Urbanized High Density Area)	Urban-Related Runoff/Stormwater	7.3
Baseflow Depletion From Groundwater Withdrawals	Hydromodification	4.5
Heap-Leach Extraction Mining	Resource Extraction	4.1
Sources Outside State Jurisdiction Or Borders	Other	2.8
Erosion From Derelict Land (Barren Land)	Hydromodification	1.8

Designated Use	Acres Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
					% Threatened
					% Impaired
Agricultural	305,033.3	82.2	.0	17.8
Aquatic Life	334,229.2	34.4	1.8	63.8
Cold Water Fishery	278,124.4	79.0	2.2	18.8
Drinking Water	531,928.6	42.7	.0	57.3
Industrial	309,138.0	97.6	.0	2.4
Primary Contact Recreation	562,243.2	44.6	.0	55.4
Warm Water Fishery	51,920.8	50.0	.0	50.0

Cause of Impairment	Cause of Impairment Group	Acres Threatened or Impaired
Mercury	Mercury	392,275.8
Lead	Metals (other than Mercury)	257,122.0
Aquatic Plants - Native	Nuisance Native Species	248,500.0
Sedimentation/Siltation	Sediment	135,721.5
Phosphorus, Total	Nutrients	135,361.2
Nitrogen, Total	Nutrients	133,206.9
Polychlorinated Biphenyls (PCBs)	Polychlorinated Biphenyls (PCBs)	129,356.8
Other Flow Regime Alterations	Flow Alteration(s)	44,980.8
Excess Algal Growth	Algal Growth	40,780.0
Arsenic	Metals (other than Mercury)	36,809.0
Ammonia, Un-ionized	Ammonia	35,180.0
Thallium	Metals (other than Mercury)	35,180.0
Salinity	Salinity/Total Dissolved Solids/Chlorides/Sulfates	13,697.0
Selenium	Metals (other than Mercury)	13,575.0
Sulfates	Salinity/Total Dissolved Solids/Chlorides/Sulfates	9,400.0
Cadmium	Metals (other than Mercury)	8,619.0
Physical Substrate Habitat Alterations	Habitat Alterations	7,780.8
Dissolved Oxygen	Organic Enrichment/Oxygen Depletion	7,652.6
Chlorophyll-A	Algal Growth	5,020.0
Other Anthropogenic Substrate Alterations	Habitat Alterations	4,455.8
Endosulfan	Pesticides	3,800.0
DDT	Pesticides	3,800.0
Total Dissolved Solids (TDS)	Salinity/Total Dissolved Solids/Chlorides/Sulfates	3,800.0
Endrin Aldehyde	Pesticides	3,800.0
Low Flow Alterations	Flow Alteration(s)	3,780.8
Cause Unknown	Cause Unknown	3,780.8
Chromium, Total	Metals (other than Mercury)	3,780.8
Solids (Suspended/Bedload)	Sediment	3,500.0
BOD, Sediment Load (Sediment Oxygen Demand)	Organic Enrichment/Oxygen Depletion	2,680.0
Copper	Metals (other than Mercury)	1,923.0
Iron	Metals (other than Mercury)	1,903.0
Total Kjehldahl Nitrogen (TKN)	Nutrients	352.6
Other Cause	Other Cause	80.0
pH	pH/Acidity/Caustic Conditions	20.0
Zinc	Metals (other than Mercury)	20.0
Alteration in Stream-Side or Littoral Vegetative Covers	Habitat Alterations	9.0

Probable Source	Probable Source Group	Acres Threatened or Impaired
Agriculture	Agriculture	305,434.1
Impacts From Abandoned Mine Lands (Inactive)	Resource Extraction	291,080.8
Atmospheric Deposition - Toxics	Atmospheric Deposition	259,099.0
Historic Bottom Deposits (Not Sediment)	Legacy/Historical Pollutants	250,500.0
Municipal Point Source Discharges	Municipal Discharges/Sewage	166,286.9
Source Unknown	Unknown	156,792.2
Impacts From Hydrostructure Flow Regulation/Modification	Hydromodification	143,389.4
Atmospheric Deposition - Nitrogen	Atmospheric Deposition	126,006.9
Unspecified Urban Stormwater	Urban-Related Runoff/Stormwater	126,006.9
Upstream Impoundments (E.G., Pl-566 Nrcs Structures)	Hydromodification	126,006.9
Silviculture Harvesting	Silviculture (Forestry)	126,006.9
Natural Sources	Natural/Wildlife	46,263.8
Acid Mine Drainage	Resource Extraction	40,560.8
Site Clearance (Land Development Or Redevelopment)	Construction	35,180.0
On-Site Treatment Systems (Septic Systems And Similar Decentralized Systems)	Municipal Discharges/Sewage	35,180.0
Internal Nutrient Recycling	Natural/Wildlife	35,180.0
Dam Or Impoundment	Hydromodification	32,350.0
Irrigated Crop Production	Agriculture	26,789.7
Silviculture Activities	Silviculture (Forestry)	8,669.9
Forest Roads (Road Construction And Use)	Silviculture (Forestry)	6,029.9
Placer Mining	Resource Extraction	5,500.0
Inappropriate Waste Disposal	Spills/Dumping	5,500.0
Rangeland Grazing	Agriculture	4,932.1
Drought-Related Impacts	Natural/Wildlife	4,888.0
Grazing In Riparian Or Shoreline Zones	Agriculture	4,852.1
Highway/Road/Bridge Runoff (Non-Construction Related)	Urban-Related Runoff/Stormwater	3,800.0
Habitat Modification - Other Than Hydromodification	Habitat Alterations (Not Directly Related To Hydromodification)	3,780.8
Highways, Roads, Bridges, Infrastructure (New Construction)	Construction	3,364.0
Upstream Source	Other	3,332.1
Low Water Crossing	Other	1,126.0
Non-Irrigated Crop Production	Agriculture	675.0
Upstream/Downstream Source	Other	352.6
Petroleum/Natural Gas Activities	Resource Extraction	9.0

Cause of Impairment Group	Size of Assessed Waters with Listed Causes of Impairment
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	Rivers and Streams (Miles)	Lakes, Reservoirs, and Ponds (Acres)
Algal Growth	1,776.4	45,800.0
Ammonia	290.4	35,180.0
Cause Unknown	249.0	3,780.8
Cause Unknown - Impaired Biota	88.1
Flow Alteration(s)	6,045.2	48,761.6
Habitat Alterations	9,196.6	8,464.8
Mercury	1,779.6	392,275.8
Metals (other than Mercury)	5,287.1	309,666.8
Nuisance Exotic Species	9.8
Nuisance Native Species	11.1	248,500.0
Nutrients	6,611.6	140,961.2
Oil and Grease	23.7
Organic Enrichment/Oxygen Depletion	692.1	10,332.6
Other Cause	108.6	80.0
Pathogens	505.9
Pesticides	21.6	3,800.0
pH/Acidity/Caustic Conditions	351.1	20.0
Polychlorinated Biphenyls (PCBs)	54.3	129,356.8
Radiation	92.3
Salinity/Total Dissolved Solids/Chlorides/Sulfates	2,607.7	17,197.0
Sediment	7,266.2	139,221.5
Temperature	2,454.4
Toxic Inorganics	142.2
Toxic Organics	36.2
Turbidity	279.9

Probable Source Group	Size of Assessed Waters with Probable Sources of Impairments
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	Rivers and Streams (Miles)	Lakes, Reservoirs, and Ponds (Acres)
Agriculture	11,519.3	319,998.8
Aquaculture	50.1
Atmospheric Deposition	70.7	385,105.9
Construction	1,598.7	38,544.0
Habitat Alterations (Not Directly Related To Hydromodification)	2,071.6	3,780.8
Hydromodification	6,887.0	175,739.4
Industrial	599.4
Legacy/Historical Pollutants	289.2	250,500.0
Municipal Discharges/Sewage	903.6	166,286.9
Natural/Wildlife	4,352.4	51,151.8
Other	120.6	3,684.7
Recreation And Tourism (Non-Boating)	208.6
Resource Extraction	2,568.6	291,089.8
Silviculture (Forestry)	1,820.2	137,356.8
Spills/Dumping	149.4	5,500.0
Unknown	4,294.8	156,792.2
Urban-Related Runoff/Stormwater	1,376.5	129,806.9

Year Attaining	Number of Waters Attaining	Number of Causes of Impairment Addressed
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	1	1
2011	2	2

Fiscal Year	Number of TMDLs	Number of Causes of Impairment Addressed
NOTE: Click on the underlined "Number of TMDLs Completed" value for a detailed list of the TMDLs for the fiscal year.
1997	10	10
1998	32	37
1999	18	33
2001	1	1
2002	16	20
2003	46	49
2004	56	75
2005	67	73
2006	124	127
2007	34	36
2008	88	117
2009	119	122
2010	98	99
2011	98	113
2012	143	200
2013	164	174

Cause of Impairment Group Name	Number of Causes of Impairment Reported
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)	637
Nutrients	494
Sediment	337
Temperature	83
Mercury	72
Salinity/Total Dissolved Solids/Chlorides/Sulfates	65
Turbidity	59
Organic Enrichment/Oxygen Depletion	22
pH/Acidity/Caustic Conditions	18
Pathogens	17
Ammonia	11
Toxic Inorganics	11
Cause Unknown - Impaired Biota	6
Pesticides	4
Other Cause	3
Polychlorinated Biphenyls (PCBs)	3
Toxic Organics	3
Radiation	2
Oil and Grease	1
Nuisance Exotic Species	1

Pollutant	Number of TMDLs	Number of Causes of Impairment Addressed
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.
Sediment	203	303
Lead	105	107
Copper	96	98
Cadmium	83	91
Zinc	73	76
Arsenic	72	74
Sedimentation/Siltation	58	61
Iron	54	55
Nitrogen, Total	45	49
Phosphorus, Total	35	40
Phosphorus	30	43
Aluminum	25	25
Temperature	25	31
Nitrogen	21	29
Mercury	20	20
Siltation	19	19
Selenium	13	13
Manganese	12	12
Thermal Modifications	10	10
Suspended Solids	9	9
Total Dissolved Solids (TDS)	9	17
Fecal Coliform	8	8
Cyanide	7	7
Escherichia Coli (E. Coli)	7	7
Fecal	7	9
Nickel	7	7
Nitrite/Nitrate	6	6
Total Residual Chlorine	6	6
Total Suspended Solids (TSS)	6	7
Ammonia	5	5
Antimony	5	6
Chromium, Total	3	3
Salinity	3	4
Silver	3	3
Tin	3	3
pH	3	3
Nitrates	2	2
Polychlorinated Biphenyls (PCBs)	2	2
Salinity/Total Dissolved Solids/Sulfates	2	2
Beryllium	1	1
Biochemical Oxygen Demand (BOD)	1	1
Fluoride	1	1
Nitrate	1	1
Nitrate/Nitrite	1	1
Noxious Aquatic Plants	1	1
Nutrients	1	3
Sulfate	1	1
Sulfates	1	1
Thallium	1	1
Total Toxics	1	1
Turbidity	1	1

Montana Water Quality Assessment Report

Features

Site-specific Targeted Monitoring Summary Results

Montana (2008)

Summary of Water Quality Assessments for Each Waterbody Typefor Reporting Year 2008

Site-specific Targeted Monitoring Results

Montana Rivers and Streams 2008

Site-specific Targeted Monitoring Results

Individual Designated Use SupportMontana Rivers and Streams 2008

Site-specific Targeted Monitoring Results

Causes of ImpairmentMontana Rivers and Streams 2008

Site-specific Targeted Monitoring Results

Probable SourcesMontana Rivers and Streams 2008

Site-specific Targeted Monitoring Results

Montana Lakes, Reservoirs, and Ponds 2008

Site-specific Targeted Monitoring Results

Individual Designated Use SupportMontana Lakes, Reservoirs, and Ponds 2008

Site-specific Targeted Monitoring Results

Causes of ImpairmentMontana Lakes, Reservoirs, and Ponds 2008

Site-specific Targeted Monitoring Results

Probable SourcesMontana Lakes, Reservoirs, and Ponds 2008

Montana Causes of Impairment for Reporting Year 2008

Montana Probable Sources Contributing to Impairmentsfor Reporting Year 2008

Montana TMDL Alternatives by Cause of Impairment 2008

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

Montana Causes of Impairment for 303(d) Listed Waters

Montana Cumulative TMDLs by Pollutant

Montana Cumulative Number of TMDLs

TMDL Document Search

Summary of Water Quality Assessments for Each Waterbody Type
for Reporting Year 2008

Individual Designated Use Support
Montana Rivers and Streams 2008

Causes of Impairment
Montana Rivers and Streams 2008

Probable Sources
Montana Rivers and Streams 2008

Individual Designated Use Support
Montana Lakes, Reservoirs, and Ponds 2008

Causes of Impairment
Montana Lakes, Reservoirs, and Ponds 2008

Probable Sources
Montana Lakes, Reservoirs, and Ponds 2008

Montana Probable Sources Contributing to Impairments
for Reporting Year 2008