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National Summary of
Impaired Waters and TMDL 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.





Impaired Waters Listed By State

Description of this table
Alabama color.gif 283
Alaska color.gif 35
American Samoa color.gif 45
Arizona color.gif 90
Arkansas color.gif 225
California color.gif 1,021
Colorado color.gif 244
Connecticut color.gif 461
Delaware color.gif 101
District Of Columbia color.gif 36
Florida color.gif 2,292
Georgia color.gif 242
Guam color.gif 47
Hawaii color.gif 298
Idaho color.gif 741
Illinois color.gif 1,057
Indiana color.gif 1,836
Iowa color.gif 480
Kansas color.gif 1,372
Kentucky color.gif 1,433
Louisiana color.gif 236
Maine color.gif 114
Maryland color.gif 184
Massachusetts color.gif 720
Michigan color.gif 2,352
Minnesota color.gif 1,144
Mississippi color.gif 229
Missouri color.gif 257
Montana color.gif 480
N. Mariana Islands color.gif 24
Nebraska color.gif 342
Nevada color.gif 215
New Hampshire color.gif 1,449
New Jersey color.gif 716
New Mexico color.gif 209
New York color.gif 1,543
North Carolina color.gif 1,130
North Dakota color.gif 201
Ohio color.gif 267
Oklahoma color.gif 657
Oregon color.gif 1,397
Pennsylvania color.gif 6,957
Puerto Rico color.gif 231
Rhode Island color.gif 120
South Carolina color.gif 961
South Dakota color.gif 166
Tennessee color.gif 1,012
Texas color.gif 719
Utah color.gif 156
Vermont color.gif 104
Virgin Islands color.gif 87
Virginia color.gif 1,523
Washington color.gif 2,420
West Virginia color.gif 1,097
Wisconsin color.gif 593
Wyoming color.gif 107

Total: 42,458 impaired waters


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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.
Pathogens color.gif 10,810
Nutrients color.gif 7,705
Metals (other than Mercury) color.gif 7,032
Organic Enrichment/Oxygen Depletion color.gif 6,723
Sediment color.gif 6,463
Polychlorinated Biphenyls (PCBs) color.gif 5,837
Mercury color.gif 4,807
pH/Acidity/Caustic Conditions color.gif 4,308
Cause Unknown - Impaired Biota color.gif 3,679
Temperature color.gif 3,130
Turbidity color.gif 2,877
Pesticides color.gif 2,092
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 1,884
Algal Growth color.gif 1,276
Cause Unknown color.gif 1,190
Habitat Alterations color.gif 849
Dioxins color.gif 656
Total Toxics color.gif 514
Other Cause color.gif 478
Toxic Organics color.gif 456
Ammonia color.gif 435
Toxic Inorganics color.gif 373
Flow Alteration(s) color.gif 220
Oil and Grease color.gif 192
Taste, Color and Odor color.gif 142
Nuisance Exotic Species color.gif 119
Fish Consumption Advisory color.gif 100
Biotoxins color.gif 87
Trash color.gif 85
Noxious Aquatic Plants color.gif 83
Cause Unknown - Fish Kills color.gif 68
Chlorine color.gif 59
Radiation color.gif 51
Nuisance Native Species color.gif 4

Total: 74,784 Causes of Impairment

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National Cumulative TMDLs by Pollutant

This chart includes TMDLs since October 1, 1995.

Description of this table
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.
Number of Causes of
Impairment Addressed
Mercury color.gif 21,545 21,575
Pathogens color.gif 12,914 13,216
Metals (other than Mercury) color.gif 9,947 10,269
Nutrients color.gif 5,949 7,174
Sediment color.gif 3,914 4,564
Temperature color.gif 2,301 2,311
Organic Enrichment/Oxygen Depletion color.gif 2,140 2,264
pH/Acidity/Caustic Conditions color.gif 1,943 2,003
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 1,707 1,765
Turbidity color.gif 1,563 1,788
Pesticides color.gif 1,218 1,318
Ammonia color.gif 1,114 1,178
Polychlorinated Biphenyls (PCBs) color.gif 495 514
Chlorine color.gif 335 341
Other Cause color.gif 268 323
Toxic Inorganics color.gif 205 205
Toxic Organics color.gif 158 199
Cause Unknown - Impaired Biota color.gif 128 132
Total Toxics color.gif 110 120
Algal Growth color.gif 89 97
Habitat Alterations color.gif 83 84
Trash color.gif 74 74
Dioxins color.gif 27 28
Noxious Aquatic Plants color.gif 21 22
Radiation color.gif 19 22
Oil and Grease color.gif 14 14
Cause Unknown color.gif 7 7
Nuisance Exotic Species color.gif 3 6
Fish Consumption Advisory color.gif 2 2

Total: 68,293 TMDLs; 71,615 Causes of Impairment Addressed

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Approved TMDLs By State

This chart includes TMDLs since October 1, 1995.

Description of this table
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.
Alabama color.gif 303
Alaska color.gif 58
American Samoa color.gif 2
Arizona color.gif 88
Arkansas color.gif 318
California color.gif 1,811
Colorado color.gif 1,005
Connecticut color.gif 407
Delaware color.gif 579
District Of Columbia color.gif 379
Florida color.gif 2,246
Georgia color.gif 1,700
Guam color.gif 18
Hawaii color.gif 65
Idaho color.gif 2,145
Illinois color.gif 429
Indiana color.gif 1,214
Iowa color.gif 205
Kansas color.gif 3,217
Kentucky color.gif 329
Louisiana color.gif 750
Maine color.gif 341
Maryland color.gif 825
Massachusetts color.gif 601
Michigan color.gif 238
Minnesota color.gif 1,674
Mississippi color.gif 1,440
Missouri color.gif 288
Montana color.gif 1,443
Nebraska color.gif 143
Nevada color.gif 67
New Hampshire color.gif 6,052
New Jersey color.gif 616
New Mexico color.gif 334
New York color.gif 717
North Carolina color.gif 13,443
North Dakota color.gif 136
Ohio color.gif 1,761
Oklahoma color.gif 704
Oregon color.gif 1,241
Pennsylvania color.gif 7,152
Puerto Rico color.gif 321
Rhode Island color.gif 217
South Carolina color.gif 521
South Dakota color.gif 329
Tennessee color.gif 1,259
Texas color.gif 252
Utah color.gif 319
Vermont color.gif 119
Virgin Islands color.gif 66
Virginia color.gif 1,463
Washington color.gif 1,486
West Virginia color.gif 4,816
Wisconsin color.gif 247
Wyoming color.gif 394

Total: 68,293 TMDLs


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National 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.
1996 color.gif 135 136
1997 color.gif 337 351
1998 color.gif 402 408
1999 color.gif 330 373
2000 color.gif 1,555 1,580
2001 color.gif 2,580 2,616
2002 color.gif 2,743 2,823
2003 color.gif 2,999 3,272
2004 color.gif 3,378 3,636
2005 color.gif 4,319 4,634
2006 color.gif 4,211 4,563
2007 color.gif 4,321 4,651
2008 color.gif 9,264 9,546
2009 color.gif 4,399 4,623
2010 color.gif 2,572 2,708
2011 color.gif 2,830 3,113
2012 color.gif 2,883 3,151
2013 color.gif 15,534 15,624
2014 color.gif 3,389 3,680
2015 color.gif 112 127

Total: 68,293 TMDLs; 71,615 Causes of Impairment Addressed

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Status of Available Data Used in This Report

Description of this table
Alabama 2012 2012
Alaska 2010 2010
American Samoa 2012 2012
Arizona 2010 2010
Arkansas 2008 2008
California 2010 2010
Colorado 2010 2010
Connecticut 2012 2012
Delaware 2006 2006
District Of Columbia 2012 2012
Florida 2010 2010
Georgia 2012 2012
Guam 2010 2010
Hawaii 2010 2010
Idaho 2012 2012
Illinois 2010 2006
Indiana 2010 2008
Iowa 2012 2012
Kansas 2014 2014
Kentucky 2012 2012
Louisiana 2012 2012
Maine 2010 2010
Maryland 2002 2010
Massachusetts 2012 2012
Michigan 2010 2008
Minnesota 2010 2008
Mississippi 2012 2012
Missouri 2012 2012
Montana 2014 2014
N. Mariana Islands 2010 2010
Nebraska 2014 2014
Nevada 2010 2010
New Hampshire 2010 2010
New Jersey 2010 2010
New Mexico 2012 2012
New York 2012 2012
North Carolina 2012 2012
North Dakota 2012 2012
Ohio 2010 2008
Oklahoma 2012 2012
Oregon 2006 2006
Pennsylvania 2006 2004
Puerto Rico 2012 2012
Rhode Island 2012 2012
South Carolina 2010 2010
South Dakota 2014 2014
Tennessee 2012 2012
Texas 2010 2010
Utah 2010 2010
Vermont 2012 2012
Virgin Islands 2012 2012
Virginia 2010 2010
Washington 2008 2008
West Virginia 2010 2010
Wisconsin 2006 2006
Wyoming 2012 2012


TMDL Document Search


Full Text Search of TMDL Documents

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Alabama Alaska American Samoa Arizona Arkansas California Colorado Connecticut Delaware Washington, DC Florida Georgia Guam Hawaii Idaho Illinois Indiana Iowa Kansas Kentucky Louisiana Maine Maryland Massachussets Michigan Minnesota Mississippi Missouri Montana Nebraska Nevada New Hampshire New Jersey New Mexico New York North Carolina North Dakota Northern Mariana Islands Ohio Oklahoma Oregon Pennsylvania Puerto Rico Rhode Island South Carolina South Dakota Tennessee Texas Trust Territories Utah Vermont Virgin Islands Virginia Washington West Virginia Wisconsin Wyoming

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