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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 220
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 113
Maryland color.gif 184
Massachusetts color.gif 720
Michigan color.gif 2,584
Minnesota color.gif 1,347
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 1,152
North Dakota color.gif 217
Ohio color.gif 267
Oklahoma color.gif 635
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: 42,909 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 10,781
Nutrients color.gif 7,861
Metals (other than Mercury) color.gif 7,049
Organic Enrichment/Oxygen Depletion color.gif 6,681
Sediment color.gif 6,466
Polychlorinated Biphenyls (PCBs) color.gif 6,193
Mercury color.gif 4,555
pH/Acidity/Caustic Conditions color.gif 4,261
Cause Unknown - Impaired Biota color.gif 3,776
Temperature color.gif 3,113
Turbidity color.gif 2,878
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 1,882
Pesticides color.gif 1,841
Algal Growth color.gif 1,293
Cause Unknown color.gif 1,184
Habitat Alterations color.gif 869
Dioxins color.gif 561
Total Toxics color.gif 516
Toxic Organics color.gif 478
Other Cause color.gif 455
Ammonia color.gif 420
Toxic Inorganics color.gif 370
Flow Alteration(s) color.gif 219
Oil and Grease color.gif 191
Nuisance Exotic Species color.gif 119
Taste, Color and Odor color.gif 102
Fish Consumption Advisory color.gif 98
Biotoxins color.gif 87
Trash color.gif 84
Noxious Aquatic Plants color.gif 84
Cause Unknown - Fish Kills color.gif 64
Chlorine color.gif 59
Radiation color.gif 51
Nuisance Native Species color.gif 4

Total: 74,645 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 13,028 13,337
Metals (other than Mercury) color.gif 9,828 10,022
Nutrients color.gif 6,038 7,308
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 499 518
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: 68,456 TMDLs; 71,708 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 581
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 830
Massachusetts color.gif 600
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 719
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 1,271
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: 68,456 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 320 384

Total: 68,456 TMDLs; 71,708 Causes of Impairment Addressed

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Status of Available Data Used in This Report

Description of this table
Alabama 2014 2014
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 2012 2012
Maryland 2002 2010
Massachusetts 2012 2012
Michigan 2010 2010
Minnesota 2010 2010
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 2014 2014
North Dakota 2014 2014
Ohio 2010 2008
Oklahoma 2014 2014
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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