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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 352
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 270
Montana color.gif 480
N. Mariana Islands color.gif 24
Nebraska color.gif 342
Nevada color.gif 210
New Hampshire color.gif 1,449
New Jersey color.gif 710
New Mexico color.gif 237
New York color.gif 1,543
North Carolina color.gif 1,130
North Dakota color.gif 217
Ohio color.gif 267
Oklahoma color.gif 657
Oregon color.gif 1,397
Pennsylvania color.gif 6,957
Puerto Rico color.gif 195
Rhode Island color.gif 120
South Carolina color.gif 907
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 663
Wyoming color.gif 107

Total: 42,538 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 10,707
Nutrients color.gif 7,762
Metals (other than Mercury) color.gif 7,050
Organic Enrichment/Oxygen Depletion color.gif 6,741
Sediment color.gif 6,480
Polychlorinated Biphenyls (PCBs) color.gif 5,887
Mercury color.gif 4,802
pH/Acidity/Caustic Conditions color.gif 4,283
Cause Unknown - Impaired Biota color.gif 3,723
Temperature color.gif 3,113
Turbidity color.gif 2,920
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 1,878
Pesticides color.gif 1,843
Algal Growth color.gif 1,310
Cause Unknown color.gif 1,180
Habitat Alterations color.gif 870
Dioxins color.gif 658
Total Toxics color.gif 518
Toxic Organics color.gif 473
Other Cause color.gif 465
Ammonia color.gif 421
Toxic Inorganics color.gif 370
Flow Alteration(s) color.gif 222
Oil and Grease color.gif 197
Taste, Color and Odor color.gif 142
Nuisance Exotic Species color.gif 119
Fish Consumption Advisory color.gif 98
Biotoxins color.gif 87
Trash color.gif 84
Noxious Aquatic Plants color.gif 83
Cause Unknown - Fish Kills color.gif 65
Chlorine color.gif 59
Radiation color.gif 51
Nuisance Native Species color.gif 4

Total: 74,665 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 13,016 13,325
Metals (other than Mercury) color.gif 9,828 10,022
Nutrients color.gif 6,034 7,303
Sediment color.gif 3,922 4,573
Temperature color.gif 2,305 2,315
Organic Enrichment/Oxygen Depletion color.gif 2,150 2,274
pH/Acidity/Caustic Conditions color.gif 1,945 2,004
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 1,710 1,768
Turbidity color.gif 1,590 1,815
Pesticides color.gif 1,233 1,339
Ammonia color.gif 1,114 1,178
Polychlorinated Biphenyls (PCBs) color.gif 498 517
Chlorine color.gif 335 341
Other Cause color.gif 268 323
Toxic Inorganics color.gif 206 206
Toxic Organics color.gif 158 199
Cause Unknown - Impaired Biota color.gif 128 132
Total Toxics color.gif 110 120
Algal Growth color.gif 93 101
Habitat Alterations color.gif 83 84
Trash color.gif 75 75
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: 68,439 TMDLs; 71,690 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 59
American Samoa color.gif 2
Arizona color.gif 88
Arkansas color.gif 318
California color.gif 1,814
Colorado color.gif 1,005
Connecticut color.gif 407
Delaware color.gif 579
District Of Columbia color.gif 385
Florida color.gif 2,246
Georgia color.gif 1,700
Guam color.gif 43
Hawaii color.gif 65
Idaho color.gif 2,162
Illinois color.gif 429
Indiana color.gif 1,214
Iowa color.gif 212
Kansas color.gif 3,253
Kentucky color.gif 329
Louisiana color.gif 750
Maine color.gif 341
Maryland color.gif 829
Massachusetts color.gif 599
Michigan color.gif 238
Minnesota color.gif 1,789
Mississippi color.gif 1,440
Missouri color.gif 288
Montana color.gif 1,444
Nebraska color.gif 171
Nevada color.gif 67
New Hampshire color.gif 6,052
New Jersey color.gif 616
New Mexico color.gif 334
New York color.gif 718
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 257
Utah color.gif 319
Vermont color.gif 119
Virgin Islands color.gif 66
Virginia color.gif 1,478
Washington color.gif 1,486
West Virginia color.gif 4,700
Wisconsin color.gif 247
Wyoming color.gif 394

Total: 68,439 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 2,742 2,822
2003 color.gif 2,999 3,272
2004 color.gif 3,392 3,650
2005 color.gif 4,319 4,634
2006 color.gif 4,204 4,555
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 3,338 3,511
2015 color.gif 303 366

Total: 68,439 TMDLs; 71,690 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 2014 2014
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 2014 2014
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 2014 2014
Montana 2014 2014
N. Mariana Islands 2014 2014
Nebraska 2014 2014
Nevada 2012 2012
New Hampshire 2010 2010
New Jersey 2012 2012
New Mexico 2014 2014
New York 2012 2012
North Carolina 2012 2012
North Dakota 2014 2014
Ohio 2010 2008
Oklahoma 2012 2012
Oregon 2006 2006
Pennsylvania 2006 2004
Puerto Rico 2014 2014
Rhode Island 2012 2012
South Carolina 2012 2012
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 2008
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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