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National Summary of State Information

Depicted below are national summary tables and charts for available water quality data reported by the States to EPA under Section 305(b) and 303(d) of the Clean Water Act.

This report displays the most current available reporting year data.
Check the Status of Available Data for more information.

Assessed Waters of United States

Incomplete state reported information may lead to discrepancies and/or missing information in these reports.

	Size of Water
	Rivers and Streams (Miles)	Lakes, Reservoirs, and Ponds (Acres)	Bays and Estuaries (Square Miles)	Coastal Shoreline (Miles)	Ocean and Near Coastal (Square Miles)	Wetlands (Acres)	Great Lakes Shoreline (Miles)	Great Lakes Open Water (Square Miles)
Good Waters	455,628	5,854,182	11,072	1,215	541	197,205	78	62
Threatened Waters	5,198	19,862
Impaired Waters	517,190	12,006,715	21,587	7,206	1,057	922,311	4,353	53,270
Total Assessed Waters	978,016	17,880,759	32,659	8,421	1,598	1,119,515	4,431	53,332
Total Waters	3,533,205	41,666,049	87,791	58,618	54,120	107,700,000	5,202	60,546
Percent of Waters Assessed	27.7	42.9	37.2	14.4	3.0	1.0	85.2	88.1

States Using a Statewide Statistical Survey

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Summary of Water Quality Assessments for Each Waterbody Type

National Summary
Water Quality Attainment in Assessed Rivers and Streams

Description of this table Assessed Status Miles Assessed 978,016 Unassessed 2,555,189 Total Miles 3,533,205

Description of this table Attainment Status Miles Good 455,628 Threatened 5,198 Impaired 517,190 Total Miles Assessed 978,016

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National Summary
Designated Use Support in Assessed Rivers and Streams*

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

Designated Use Group		Miles Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
						% Threatened
						% Impaired
	Fish, Shellfish, And Wildlife Protection And Propagation	761,035	55.5	.4	44.1
	Recreation	387,185	56.8	1.0	42.1
	Agricultural	352,845	95.4	.2	4.5
	Aquatic Life Harvesting	254,742	36.2	.1	63.7
	Industrial	197,877	97.8	.0	2.2
	Public Water Supply	196,978	77.5	.1	22.5
	Other	85,231	97.9	.0	2.1
	Aesthetic Value	26,213	88.9	.0	11.1
	Exceptional Recreational Or Ecological Significance	2,478	72.6	.0	27.4

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National Summary
Causes of Impairment in Assessed Rivers and Streams

Cause of Impairment Group	Miles Threatened or Impaired
Pathogens	157,682
Sediment	125,164
Nutrients	98,381
Organic Enrichment/Oxygen Depletion	84,771
Polychlorinated Biphenyls (PCBs)	78,257
Metals (other than Mercury)	75,784
Temperature	67,223
Mercury	63,740
Habitat Alterations	62,373
Flow Alteration(s)	40,739
Cause Unknown	39,187
Cause Unknown - Impaired Biota	39,003
Salinity/Total Dissolved Solids/Chlorides/Sulfates	34,259
Turbidity	29,275
pH/Acidity/Caustic Conditions	28,578
Pesticides	16,819
Other Cause	11,950
Ammonia	11,778
Fish Consumption Advisory	9,948
Total Toxics	8,999
Toxic Inorganics	7,879
Algal Growth	5,945
Toxic Organics	4,474
Dioxins	4,321
Oil and Grease	2,874
Biotoxins	2,150
Nuisance Exotic Species	1,406
Cause Unknown - Fish Kills	1,371
Taste, Color and Odor	871
Trash	751
Radiation	630
Chlorine	618
Noxious Aquatic Plants	295
Nuisance Native Species	127

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National Summary
Probable Sources of Impairments in Assessed Rivers and Streams

Probable Source Group	Miles Threatened or Impaired
Agriculture	124,177
Atmospheric Deposition	101,283
Unknown	99,012
Hydromodification	57,760
Urban-Related Runoff/Stormwater	55,956
Municipal Discharges/Sewage	53,662
Natural/Wildlife	53,170
Unspecified Nonpoint Source	48,282
Habitat Alterations (Not Directly Related To Hydromodification)	33,211
Resource Extraction	29,096
Silviculture (Forestry)	19,760
Industrial	16,158
Construction	12,576
Other	8,889
Land Application/Waste Sites/Tanks	7,917
Legacy/Historical Pollutants	4,908
Spills/Dumping	2,818
Recreation And Tourism (Non-Boating)	1,613
Aquaculture	318
Groundwater Loadings/Withdrawals	270
Recreational Boating And Marinas	132
Military Bases	42

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National Summary
Water Quality Attainment in Assessed Lakes, Reservoirs, and Ponds

Description of this table Assessed Status Acres Assessed 17,880,759 Unassessed 23,785,290 Total Acres 41,666,049

Description of this table Attainment Status Acres Good 5,854,182 Threatened 19,862 Impaired 12,006,715 Total Acres Assessed 17,880,759

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National Summary
Designated Use Support in Assessed Lakes, Reservoirs, and Ponds*

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

Designated Use Group		Acres Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
						% Threatened
						% Impaired
	Aquatic Life Harvesting	10,096,743	25.5	.0	74.5
	Fish, Shellfish, And Wildlife Protection And Propagation	9,646,501	58.7	.1	41.2
	Recreation	8,143,251	86.0	.2	13.8
	Public Water Supply	6,382,193	81.7	.0	18.3
	Agricultural	4,898,635	95.8	.0	4.2
	Industrial	3,304,709	99.9	.0	.1
	Other	2,520,363	87.4	.0	12.6
	Aesthetic Value	1,201,350	52.9	.0	47.1

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National Summary
Causes of Impairment in Assessed Lakes, Reservoirs, and Ponds

Cause of Impairment Group	Acres Threatened or Impaired
Mercury	7,452,118
Nutrients	3,055,444
Polychlorinated Biphenyls (PCBs)	2,839,921
Organic Enrichment/Oxygen Depletion	1,607,785
Turbidity	1,372,482
Metals (other than Mercury)	964,674
Algal Growth	892,475
pH/Acidity/Caustic Conditions	886,947
Sediment	717,578
Nuisance Exotic Species	679,042
Fish Consumption Advisory	501,212
Salinity/Total Dissolved Solids/Chlorides/Sulfates	456,484
Habitat Alterations	288,060
Pathogens	271,917
Other Cause	269,946
Pesticides	260,342
Ammonia	210,141
Temperature	205,815
Flow Alteration(s)	181,857
Taste, Color and Odor	147,152
Dioxins	119,568
Cause Unknown	102,688
Cause Unknown - Impaired Biota	58,062
Noxious Aquatic Plants	45,665
Nuisance Native Species	27,318
Biotoxins	17,261
Total Toxics	12,571
Cause Unknown - Fish Kills	6,457
Toxic Organics	5,806
Toxic Inorganics	4,355
Trash	1,718
Oil and Grease	1,321
Radiation	48

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National Summary
Probable Sources of Impairments in Assessed Lakes, Reservoirs, and Ponds

Probable Source Group	Acres Threatened or Impaired
Atmospheric Deposition	4,809,011
Unknown	3,201,602
Agriculture	849,373
Legacy/Historical Pollutants	772,959
Natural/Wildlife	701,159
Other	657,612
Municipal Discharges/Sewage	633,710
Unspecified Nonpoint Source	576,935
Hydromodification	572,545
Urban-Related Runoff/Stormwater	525,519
Resource Extraction	386,642
Construction	209,169
Industrial	203,180
Spills/Dumping	194,455
Silviculture (Forestry)	135,251
Habitat Alterations (Not Directly Related To Hydromodification)	124,515
Recreation And Tourism (Non-Boating)	99,369
Land Application/Waste Sites/Tanks	44,259
Commercial Harbor And Port Activities	23,046
Recreational Boating And Marinas	18,351
Aquaculture	4,620
Military Bases	2,436
Groundwater Loadings/Withdrawals	235

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National Summary
Water Quality Attainment in Assessed Bays and Estuaries

Description of this table Assessed Status Square Miles Assessed 32,659 Unassessed 55,131 Total Square Miles 87,791

Description of this table Attainment Status Square Miles Good 11,072 Threatened 0 Impaired 21,587 Total Square Miles Assessed 32,659

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National Summary
Designated Use Support in Assessed Bays and Estuaries*

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

Designated Use Group		Square Miles Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
						% Threatened
						% Impaired
	Aquatic Life Harvesting	23,453	33.1	.0	66.9
	Fish, Shellfish, And Wildlife Protection And Propagation	19,398	52.1	.0	47.9
	Recreation	13,536	88.6	.0	11.4
	Agricultural	3,786	96.7	.0	3.3
	Industrial	3,225	100.0	.0	.0
	Other	3,203	98.9	.0	1.1
	Public Water Supply	175	89.5	.0	10.5
	Aesthetic Value	114	86.6	.0	13.4

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National Summary
Causes of Impairment in Assessed Bays and Estuaries

Cause of Impairment Group	Square Miles Threatened or Impaired
Mercury	10,809
Polychlorinated Biphenyls (PCBs)	7,291
Pathogens	6,551
Organic Enrichment/Oxygen Depletion	5,204
Dioxins	4,418
Noxious Aquatic Plants	1,855
Pesticides	1,766
Metals (other than Mercury)	1,590
Algal Growth	1,412
Cause Unknown - Impaired Biota	1,165
Nutrients	880
Other Cause	777
Nuisance Exotic Species	656
Turbidity	380
Total Toxics	332
Trash	288
Fish Consumption Advisory	230
Sediment	223
pH/Acidity/Caustic Conditions	95
Toxic Organics	78
Cause Unknown	40
Salinity/Total Dissolved Solids/Chlorides/Sulfates	38
Temperature	35
Ammonia	31
Oil and Grease	16
Toxic Inorganics	6
Taste, Color and Odor	6
Habitat Alterations	0
Flow Alteration(s)	0

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National Summary
Probable Sources of Impairments in Assessed Bays and Estuaries

Probable Source Group	Square Miles Threatened or Impaired
Atmospheric Deposition	8,026
Unknown	5,825
Municipal Discharges/Sewage	4,846
Industrial	4,240
Natural/Wildlife	3,996
Other	3,779
Unspecified Nonpoint Source	2,832
Agriculture	2,547
Urban-Related Runoff/Stormwater	2,189
Habitat Alterations (Not Directly Related To Hydromodification)	2,057
Hydromodification	1,939
Legacy/Historical Pollutants	1,476
Resource Extraction	1,290
Recreational Boating And Marinas	1,028
Commercial Harbor And Port Activities	495
Spills/Dumping	283
Land Application/Waste Sites/Tanks	11
Construction	4
Recreation And Tourism (Non-Boating)	3
Land Application/Waste Sites	1
Groundwater Loadings/Withdrawals	0
Silviculture (Forestry)	0
Aquaculture	0

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National Summary
Water Quality Attainment in Assessed Coastal Shoreline

Description of this table Assessed Status Miles Assessed 8,421 Unassessed 50,197 Total Miles 58,618

Description of this table Attainment Status Miles Good 1,215 Threatened 0 Impaired 7,206 Total Miles Assessed 8,421

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National Summary
Designated Use Support in Assessed Coastal Shoreline*

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

Designated Use Group		Miles Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
						% Threatened
						% Impaired
	Aquatic Life Harvesting	7,399	9.0	.0	91.0
	Recreation	1,663	76.1	.0	23.9
	Fish, Shellfish, And Wildlife Protection And Propagation	815	68.2	.0	31.8
	Aesthetic Value	235	100.0	.0	.0
	Other	87	.0	.0	100.0
	Industrial	30	83.3	.0	16.7

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National Summary
Causes of Impairment in Assessed Coastal Shoreline

Cause of Impairment Group	Miles Threatened or Impaired
Mercury	6,473
Pathogens	1,085
Organic Enrichment/Oxygen Depletion	423
Turbidity	129
Nutrients	123
Algal Growth	91
Polychlorinated Biphenyls (PCBs)	76
Cause Unknown - Impaired Biota	70
pH/Acidity/Caustic Conditions	69
Metals (other than Mercury)	62
Other Cause	45
Pesticides	44
Ammonia	21
Temperature	20
Oil and Grease	13
Sediment	5

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National Summary
Probable Sources of Impairments in Assessed Coastal Shoreline

Probable Source Group	Miles Threatened or Impaired
Unknown	469
Atmospheric Deposition	388
Municipal Discharges/Sewage	327
Urban-Related Runoff/Stormwater	271
Hydromodification	136
Unspecified Nonpoint Source	135
Industrial	126
Agriculture	126
Recreational Boating And Marinas	35
Construction	20
Spills/Dumping	13
Land Application/Waste Sites/Tanks	11
Legacy/Historical Pollutants	8
Aquaculture	5
Natural/Wildlife	1
Recreation And Tourism (Non-Boating)	0
Resource Extraction	0

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National Summary
Water Quality Attainment in Assessed Ocean and Near Coastal

Description of this table Assessed Status Square Miles Assessed 1,598 Unassessed 52,522 Total Square Miles 54,120

Description of this table Attainment Status Square Miles Good 541 Threatened 0 Impaired 1,057 Total Square Miles Assessed 1,598

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National Summary
Designated Use Support in Assessed Ocean and Near Coastal*

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

Designated Use Group		Square Miles Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
						% Threatened
						% Impaired
	Recreation	1,050	97.0	.0	3.0
	Aquatic Life Harvesting	888	7.0	.0	93.0
	Fish, Shellfish, And Wildlife Protection And Propagation	840	35.1	.0	64.9
	Other	376	46.7	.0	53.3
	Agricultural	201	100.0	.0	.0

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National Summary
Causes of Impairment in Assessed Ocean and Near Coastal

Cause of Impairment Group	Square Miles Threatened or Impaired
Mercury	796
Organic Enrichment/Oxygen Depletion	579
Pesticides	567
Polychlorinated Biphenyls (PCBs)	531
Pathogens	80
Nuisance Exotic Species	35
Total Toxics	29
Turbidity	22
Metals (other than Mercury)	15
Toxic Organics	14
Habitat Alterations	10
Dioxins	9
Nutrients	7
pH/Acidity/Caustic Conditions	7
Temperature	1
Ammonia	1

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National Summary
Probable Sources of Impairments in Assessed Ocean and Near Coastal

Probable Source Group	Square Miles Threatened or Impaired
Atmospheric Deposition	777
Unknown	602
Urban-Related Runoff/Stormwater	452
Municipal Discharges/Sewage	116
Recreational Boating And Marinas	9
Unspecified Nonpoint Source	7
Recreation And Tourism (Non-Boating)	4
Industrial	4
Hydromodification	4
Construction	3
Spills/Dumping	2
Natural/Wildlife	1
Commercial Harbor And Port Activities	0

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National Summary
Water Quality Attainment in Assessed Wetlands

Description of this table Assessed Status Acres Assessed 1,119,515 Unassessed 106,580,485 Total Acres 107,700,000

Description of this table Attainment Status Acres Good 197,205 Threatened 0 Impaired 922,311 Total Acres Assessed 1,119,515

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National Summary
Designated Use Support in Assessed Wetlands*

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

Designated Use Group		Acres Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
						% Threatened
						% Impaired
	Fish, Shellfish, And Wildlife Protection And Propagation	1,112,731	17.3	.0	82.7
	Recreation	1,048,237	54.9	.0	45.1
	Public Water Supply	480,401	99.8	.0	.2
	Aquatic Life Harvesting	33,495	.5	.0	99.5
	Agricultural	19,037	85.4	.0	14.6
	Industrial	19,032	100.0	.0	.0
	Other	719	100.0	.0	.0

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National Summary
Causes of Impairment in Assessed Wetlands

Cause of Impairment Group	Acres Threatened or Impaired
Organic Enrichment/Oxygen Depletion	860,167
Pathogens	464,029
Mercury	231,260
Metals (other than Mercury)	28,823
Toxic Inorganics	28,053
Sediment	11,405
Salinity/Total Dissolved Solids/Chlorides/Sulfates	8,634
Temperature	7,680
Flow Alteration(s)	4,417
Turbidity	4,089
Algal Growth	3,891
Nuisance Exotic Species	2,989
Nutrients	1,873
Habitat Alterations	1,754
Cause Unknown - Impaired Biota	1,263
Cause Unknown	1,000
Fish Consumption Advisory	1,000
Cause Unknown - Fish Kills	997
Noxious Aquatic Plants	940
pH/Acidity/Caustic Conditions	838
Polychlorinated Biphenyls (PCBs)	707
Other Cause	678
Trash	458
Toxic Organics	0
Pesticides	0
Ammonia	0
Total Toxics	0

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National Summary
Probable Sources of Impairments in Assessed Wetlands

Probable Source Group	Acres Threatened or Impaired
Unknown	707,599
Natural/Wildlife	472,619
Municipal Discharges/Sewage	464,479
Atmospheric Deposition	200,741
Agriculture	199,062
Industrial	195,840
Resource Extraction	32,215
Hydromodification	14,947
Habitat Alterations (Not Directly Related To Hydromodification)	7,680
Land Application/Waste Sites/Tanks	1,138
Unspecified Nonpoint Source	1,098
Construction	1,000
Other	237
Urban-Related Runoff/Stormwater	104

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National Summary
Water Quality Attainment in Assessed Great Lakes Shoreline

Description of this table Assessed Status Miles Assessed 4,431 Unassessed 772 Total Miles 5,202

Description of this table Attainment Status Miles Good 78 Threatened 0 Impaired 4,353 Total Miles Assessed 4,431

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National Summary
Designated Use Support in Assessed Great Lakes Shoreline*

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

Designated Use Group		Miles Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
						% Threatened
						% Impaired
	Aquatic Life Harvesting	4,064	.0	.0	100.0
	Agricultural	3,131	100.0	.0	.0
	Other	3,131	100.0	.0	.0
	Industrial	3,131	100.0	.0	.0
	Fish, Shellfish, And Wildlife Protection And Propagation	865	33.1	.0	66.9
	Recreation	816	32.2	.0	67.8
	Public Water Supply	336	100.0	.0	.0

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National Summary
Causes of Impairment in Assessed Great Lakes Shoreline

Cause of Impairment Group	Miles Threatened or Impaired
Polychlorinated Biphenyls (PCBs)	3,472
Dioxins	2,963
Mercury	2,194
Pesticides	1,975
Pathogens	492
Nutrients	315
Nuisance Exotic Species	290
Sediment	290
Fish Consumption Advisory	285
Habitat Alterations	170
Other Cause	152
Organic Enrichment/Oxygen Depletion	120
Algal Growth	25
Toxic Inorganics	5

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National Summary
Probable Sources of Impairments in Assessed Great Lakes Shoreline

Probable Source Group	Miles Threatened or Impaired
Atmospheric Deposition	3,400
Agriculture	536
Legacy/Historical Pollutants	427
Unknown	141
Municipal Discharges/Sewage	120
Land Application/Waste Sites/Tanks	31
Industrial	31
Unspecified Nonpoint Source	8
Hydromodification	7
Urban-Related Runoff/Stormwater	2
Natural/Wildlife	0

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National Summary
Water Quality Attainment in Assessed Great Lakes Open Water

Description of this table Assessed Status Square Miles Assessed 53,332 Unassessed 7,214 Total Square Miles 60,546

Description of this table Attainment Status Square Miles Good 62 Threatened 0 Impaired 53,270 Total Square Miles Assessed 53,332

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National Summary
Designated Use Support in Assessed Great Lakes Open Water*

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

Designated Use Group		Square Miles Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
						% Threatened
						% Impaired
	Aquatic Life Harvesting	39,184	.0	.0	100.0
	Industrial	39,031	100.0	.0	.0
	Agricultural	39,031	100.0	.0	.0
	Other	39,031	100.0	.0	.0
	Fish, Shellfish, And Wildlife Protection And Propagation	14,300	1.5	.0	98.5
	Public Water Supply	151	100.0	.0	.0
	Recreation	151	100.0	.0	.0

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National Summary
Causes of Impairment in Assessed Great Lakes Open Water

Cause of Impairment Group	Square Miles Threatened or Impaired
Polychlorinated Biphenyls (PCBs)	39,183
Dioxins	38,862
Mercury	29,968
Pesticides	29,661
Fish Consumption Advisory	14,087
Organic Enrichment/Oxygen Depletion	13,867
Total Toxics	192
Nuisance Exotic Species	25

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National Summary
Probable Sources of Impairments in Assessed Great Lakes Open Water

Probable Source Group	Square Miles Threatened or Impaired
Atmospheric Deposition	53,270
Legacy/Historical Pollutants	13,991
Urban-Related Runoff/Stormwater	13,867
Agriculture	4,373
Unknown	310
Other	25

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National Causes of Impairment

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National Probable Sources Contributing to Impairments

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National Previously Impaired Waters Now Attaining All Uses

NOTE: Click on the underlined "Number of Waters Attaining" value for a detailed list of those waters now attaining all uses.
Cycle Attaining	Number of Waters Attaining	Number of Causes of Impairment Addressed
2002	23	24
2003	4	7
2004	159	204
2005	107	234
2006	85	101
2007	233	399
2008	339	421
2009	318	515
2010	344	423
2011	252	301
2012	244	359
2013	3	4

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Impaired Waters Listed By State

State Name	Number of Waters on 303(d) List
Alabama	209
Alaska	35
American Samoa	44
Arizona	79
Arkansas	225
California	1,021
Colorado	244
Connecticut	425
Delaware	101
District Of Columbia	36
Florida	2,292
Georgia	215
Guam	47
Hawaii	309
Idaho	916
Illinois	1,057
Indiana	1,836
Iowa	474
Kansas	1,330
Kentucky	1,300
Louisiana	274
Maine	114
Maryland	184
Massachusetts	710
Michigan	2,352
Minnesota	1,144
Mississippi	180
Missouri	257
Montana	584
N. Mariana Islands	24
Nebraska	330
Nevada	181
New Hampshire	1,449
New Jersey	716
New Mexico	196
New York	528
North Carolina	1,270
North Dakota	201
Ohio	267
Oklahoma	723
Oregon	1,397
Pennsylvania	6,957
Puerto Rico	165
Rhode Island	120
South Carolina	961
South Dakota	155
Tennessee	1,028
Texas	719
Utah	156
Vermont	126
Virgin Islands	87
Virginia	1,523
Washington	2,420
West Virginia	1,097
Wisconsin	593
Wyoming	107

Total: 41,490 impaired waters

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National Cumulative TMDLs by Pollutant

This chart includes TMDLs since October 1, 1995.

NOTE: Click on the underlined "Pollutant Group" value to see a detailed list of pollutants. Click on the underlined "Number of TMDLs" value to see a listing of those TMDLs for the pollutant Group.
Pollutant Group	Number of TMDLs	Number of Causes of Impairment Addressed
Pathogens	11,363	11,696
Metals (other than Mercury)	8,845	9,049
Mercury	7,031	7,063
Nutrients	5,402	6,509
Sediment	3,768	4,383
Temperature	2,140	2,149
Organic Enrichment/Oxygen Depletion	1,967	2,087
pH/Acidity/Caustic Conditions	1,837	1,877
Salinity/Total Dissolved Solids/Chlorides/Sulfates	1,576	1,632
Turbidity	1,435	1,645
Pesticides	1,172	1,270
Ammonia	1,093	1,158
Polychlorinated Biphenyls (PCBs)	488	510
Chlorine	335	341
Other Cause	268	323
Toxic Inorganics	199	200
Toxic Organics	158	199
Cause Unknown - Impaired Biota	128	132
Total Toxics	103	111
Habitat Alterations	83	84
Algal Growth	72	79
Trash	72	76
Dioxins	27	28
Noxious Aquatic Plants	21	22
Radiation	19	22
Oil and Grease	14	14
Cause Unknown	7	7
Nuisance Exotic Species	3	6
Fish Consumption Advisory	2	2

Total: 49,628 TMDLs; 52,674 Causes of Impairment Addressed

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Approved TMDLs By State

This chart includes TMDLs since October 1, 1995.

NOTE: Click on the state name to see a state report. Click on the Number of TMDLs to see a detailed list of the TMDLs.
State Name	Number of TMDLs
Alabama	287
Alaska	53
American Samoa	2
Arizona	86
Arkansas	271
California	1,568
Colorado	988
Connecticut	325
Delaware	576
District Of Columbia	371
Florida	863
Georgia	1,662
Guam	18
Hawaii	64
Idaho	1,949
Illinois	341
Indiana	1,045
Iowa	188
Kansas	2,982
Kentucky	251
Louisiana	750
Maine	337
Maryland	767
Massachusetts	576
Michigan	237
Minnesota	1,384
Mississippi	1,430
Missouri	288
Montana	1,114
Nebraska	108
Nevada	64
New Hampshire	6,006
New Jersey	616
New Mexico	311
New York	663
North Carolina	220
North Dakota	123
Ohio	1,594
Oklahoma	615
Oregon	1,241
Pennsylvania	7,058
Puerto Rico	321
Rhode Island	190
South Carolina	485
South Dakota	321
Tennessee	1,210
Texas	224
Utah	308
Vermont	119
Virgin Islands	66
Virginia	1,393
Washington	1,468
West Virginia	3,531
Wisconsin	247
Wyoming	353

Total: 49,628 TMDLs

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National Cumulative Number of TMDLs

EPA Fiscal Year starts October 1 and ends September 30.

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	122	123
1997	337	351
1998	402	408
1999	330	373
2000	1,556	1,581
2001	2,577	2,613
2002	2,737	2,820
2003	3,002	3,278
2004	3,374	3,631
2005	4,312	4,630
2006	4,209	4,560
2007	4,321	4,650
2008	9,264	9,547
2009	4,398	4,627
2010	2,564	2,703
2011	2,819	3,112
2012	2,884	3,158
2013	420	509

Total: 49,628 TMDLs; 52,674 Causes of Impairment Addressed

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Status of Available Data Used in This Report

TMDL Document Search

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