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National Summary of State Information

Map of the United States

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.

Description of this table
 
    477,805 6,690,496 17,049 973 863 1,307,742 70 1,114
    9,518 71,165 17     805    
    401,357 11,301,721 11,152 709 4,265 745,616 1,214 210,022
888,679 18,063,381 28,218 1,681 5,128 2,054,164 1,284 211,136
3,533,205 41,666,049 87,791 58,618 54,120 107,700,000 5,202 60,546
25.2 43.4 32.1 2.9 9.5 1.9 24.7 100.0

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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 888,679
Unassessed 2,644,526
Total Miles 3,533,205







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Description of this table
Good 477,805
Threatened 9,518
Impaired 401,357
Total Miles Assessed 888,679

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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.

Description of this table
% Good
% Threatened
% Impaired
Fish, Shellfish, and Wildlife Protection and Propagation Fish, Shellfish, And Wildlife Protection And Propagation 523,092 56.6 .6 42.8 color.gifcolor.gifcolor.gif
Recreation Recreation 239,819 64.8 1.5 33.7 color.gifcolor.gifcolor.gif
Agricultural Agricultural 232,846 90.4 .7 8.9 color.gifcolor.gifcolor.gif
Aquatic Life Harvesting Aquatic Life Harvesting 140,185 36.6 4.7 58.6 color.gifcolor.gifcolor.gif
Public Water Supply Public Water Supply 136,997 77.6 1.4 21.0 color.gifcolor.gifcolor.gif
Industrial Industrial 108,375 88.9 .1 11.0 color.gifcolor.gifcolor.gif
Hydropower Generation Other 67,207 79.5 .4 20.1 color.gifcolor.gifcolor.gif
Aesthetic Value Aesthetic Value 19,301 72.7 6.5 20.8 color.gifcolor.gifcolor.gif
Exceptional Recreational or Ecological Significance Exceptional Recreational Or Ecological Significance 15,317 13.6 4.2 82.2 color.gifcolor.gifcolor.gif

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National Summary
Causes of Impairment in Assessed Rivers and Streams

Description of this table
Pathogens color.gif 112,084
Sediment color.gif 85,248
Nutrients color.gif 81,279
Metals (other than Mercury) color.gif 61,165
Organic Enrichment/Oxygen Depletion color.gif 59,879
Habitat Alterations color.gif 58,909
Polychlorinated Biphenyls (PCBs) color.gif 44,359
Temperature color.gif 38,228
Flow Alteration(s) color.gif 36,893
Mercury color.gif 34,152
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 28,087
pH/Acidity/Caustic Conditions color.gif 26,659
Cause Unknown - Impaired Biota color.gif 26,424
Cause Unknown color.gif 22,607
Turbidity color.gif 21,753
Pesticides color.gif 15,201
Fish Consumption Advisory color.gif 9,715
Other Cause color.gif 7,382
Ammonia color.gif 6,992
Algal Growth color.gif 5,470
Dioxins color.gif 5,446
Total Toxics color.gif 4,610
Toxic Organics color.gif 4,038
Toxic Inorganics color.gif 3,015
Oil and Grease color.gif 1,838
Chlorine color.gif 1,035
Nuisance Exotic Species color.gif 999
Taste, Color and Odor color.gif 833
Radiation color.gif 599
Trash color.gif 362
Noxious Aquatic Plants color.gif 330
Cause Unknown - Fish Kills color.gif 248
Nuisance Native Species color.gif 26
Biotoxins color.gif 23

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National Summary
Probable Sources of Impairments in Assessed Rivers and Streams

Description of this table
Agriculture color.gif 97,558
Unknown color.gif 70,561
Hydromodification color.gif 62,689
Atmospheric Deposition color.gif 49,900
Municipal Dishcarges/Sewage color.gif 45,997
Natural/Wildlife color.gif 42,808
Unspecified Nonpoint Source color.gif 37,494
Habitat Alterations (Not Directly Related To Hydromodification) color.gif 36,767
Resource Extraction color.gif 29,367
Urban-Related Runoff/Stormwater color.gif 29,296
Industrial color.gif 24,119
Silviculture (Forestry) color.gif 19,126
Legacy/Historical Pollutants color.gif 14,615
Construction color.gif 14,511
Other color.gif 11,326
Land Application/Waste Sites/Tanks color.gif 8,171
Spills/Dumping color.gif 2,024
Recreation And Tourism (Non-Boating) color.gif 1,809
Aquaculture color.gif 1,033
Recreational Boating And Marinas color.gif 201
Groundwater Loadings/Withdrawals color.gif 201
Military Bases color.gif 42

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

Description of this table
Assessed 18,063,381
Unassessed 23,602,668
Total Acres 41,666,049







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Description of this table
Good 6,690,496
Threatened 71,165
Impaired 11,301,721
Total Acres Assessed 18,063,381

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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.

Description of this table
% Good
% Threatened
% Impaired
Fish, Shellfish, and Wildlife Protection and Propagation Fish, Shellfish, And Wildlife Protection And Propagation 7,710,776 50.2 .6 49.1 color.gifcolor.gifcolor.gif
Recreation Recreation 4,488,776 61.4 2.2 36.4 color.gifcolor.gifcolor.gif
Agricultural Agricultural 3,406,492 85.0 1.1 13.8 color.gifcolor.gifcolor.gif
Aquatic Life Harvesting Aquatic Life Harvesting 3,231,078 32.3 1.9 65.8 color.gifcolor.gifcolor.gif
Public Water Supply Public Water Supply 2,969,033 62.5 1.4 36.1 color.gifcolor.gifcolor.gif
Industrial Industrial 2,747,412 82.7 .1 17.2 color.gifcolor.gifcolor.gif
Hydropower Generation Other 1,890,087 65.2 .5 34.2 color.gifcolor.gifcolor.gif
Aesthetic Value Aesthetic Value 1,230,834 25.8 1.7 72.5 color.gifcolor.gifcolor.gif
Exceptional Recreational or Ecological Significance Exceptional Recreational Or Ecological Significance 732,768 16.1 15.6 68.3 color.gifcolor.gifcolor.gif

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

Description of this table
Mercury color.gif 5,984,523
Nutrients color.gif 2,516,227
Polychlorinated Biphenyls (PCBs) color.gif 2,446,735
Organic Enrichment/Oxygen Depletion color.gif 1,939,565
Metals (other than Mercury) color.gif 1,346,933
Turbidity color.gif 1,022,138
Algal Growth color.gif 920,578
Sediment color.gif 755,822
Nuisance Exotic Species color.gif 624,698
Pathogens color.gif 555,258
Flow Alteration(s) color.gif 534,641
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 512,687
pH/Acidity/Caustic Conditions color.gif 497,221
Temperature color.gif 486,169
Fish Consumption Advisory color.gif 485,508
Habitat Alterations color.gif 446,539
Pesticides color.gif 335,556
Taste, Color and Odor color.gif 281,861
Nuisance Native Species color.gif 277,458
Toxic Organics color.gif 256,385
Ammonia color.gif 138,738
Total Toxics color.gif 106,774
Cause Unknown - Impaired Biota color.gif 75,855
Noxious Aquatic Plants color.gif 51,021
Radiation color.gif 48,264
Dioxins color.gif 44,931
Cause Unknown color.gif 41,421
Oil and Grease color.gif 40,903
Biotoxins color.gif 9,111
Other Cause color.gif 7,442
Toxic Inorganics color.gif 6,062
Cause Unknown - Fish Kills color.gif 4,614
Trash color.gif 1,701
Chlorine color.gif 50

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

Description of this table
Atmospheric Deposition color.gif 3,571,355
Unknown color.gif 2,656,091
Agriculture color.gif 1,494,046
Hydromodification color.gif 1,185,854
Natural/Wildlife color.gif 1,159,650
Other color.gif 820,570
Legacy/Historical Pollutants color.gif 762,587
Unspecified Nonpoint Source color.gif 724,617
Urban-Related Runoff/Stormwater color.gif 683,293
Municipal Dishcarges/Sewage color.gif 547,351
Resource Extraction color.gif 512,631
Habitat Alterations (Not Directly Related To Hydromodification) color.gif 360,281
Construction color.gif 304,812
Silviculture (Forestry)