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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 209
Alaska color.gif 35
American Samoa color.gif 44
Arizona color.gif 79
Arkansas color.gif 225
California color.gif 1,021
Colorado color.gif 244
Connecticut color.gif 425
Delaware color.gif 101
District Of Columbia color.gif 36
Florida color.gif 2,292
Georgia color.gif 215
Guam color.gif 47
Hawaii color.gif 309
Idaho color.gif 916
Illinois color.gif 1,057
Indiana color.gif 1,836
Iowa color.gif 474
Kansas color.gif 1,330
Kentucky color.gif 1,300
Louisiana color.gif 274
Maine color.gif 114
Maryland color.gif 184
Massachusetts color.gif 710
Michigan color.gif 2,352
Minnesota color.gif 1,144
Mississippi color.gif 180
Missouri color.gif 257
Montana color.gif 584
N. Mariana Islands color.gif 24
Nebraska color.gif 330
Nevada color.gif 181
New Hampshire color.gif 1,449
New Jersey color.gif 716
New Mexico color.gif 196
New York color.gif 528
North Carolina color.gif 1,270
North Dakota color.gif 201
Ohio color.gif 267
Oklahoma color.gif 723
Oregon color.gif 1,397
Pennsylvania color.gif 6,957
Puerto Rico color.gif 165
Rhode Island color.gif 120
South Carolina color.gif 961
South Dakota color.gif 155
Tennessee color.gif 1,028
Texas color.gif 719
Utah color.gif 156
Vermont color.gif 126
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: 41,490 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 10,641
Metals (other than Mercury) color.gif 7,536
Nutrients color.gif 6,877
Organic Enrichment/Oxygen Depletion color.gif 6,392
Sediment color.gif 6,162
Polychlorinated Biphenyls (PCBs) color.gif 5,598
Mercury color.gif 4,769
pH/Acidity/Caustic Conditions color.gif 4,179
Cause Unknown - Impaired Biota color.gif 3,568
Temperature color.gif 3,119
Turbidity color.gif 2,992
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 1,980
Pesticides color.gif 1,910
Cause Unknown color.gif 1,198
Algal Growth color.gif 1,052
Habitat Alterations color.gif 775
Dioxins color.gif 626
Total Toxics color.gif 448
Toxic Organics color.gif 398
Ammonia color.gif 383
Toxic Inorganics color.gif 381
Other Cause color.gif 266
Noxious Aquatic Plants color.gif 161
Oil and Grease color.gif 134
Flow Alteration(s) color.gif 128
Taste, Color and Odor color.gif 118
Fish Consumption Advisory color.gif 97
Biotoxins color.gif 83
Cause Unknown - Fish Kills color.gif 83
Trash color.gif 68
Radiation color.gif 45
Chlorine color.gif 41
Nuisance Exotic Species color.gif 37
Nuisance Native Species color.gif 3

Total: 72,248 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
Pathogens color.gif 11,360 11,677
Metals (other than Mercury) color.gif 8,843 9,047
Mercury color.gif 7,031 7,063
Nutrients color.gif 5,402 6,509
Sediment color.gif 3,768 4,383
Temperature color.gif 2,140 2,149
Organic Enrichment/Oxygen Depletion color.gif 1,967 2,087
pH/Acidity/Caustic Conditions color.gif 1,837 1,877
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 1,576 1,632
Turbidity color.gif 1,434 1,644
Pesticides color.gif 1,172 1,270
Ammonia color.gif 1,093 1,158
Polychlorinated Biphenyls (PCBs) color.gif 488 510
Chlorine color.gif 335 341
Other Cause color.gif 268 323
Toxic Inorganics color.gif 199 200
Toxic Organics color.gif 158 199
Cause Unknown - Impaired Biota color.gif 128 132
Total Toxics color.gif 103 111
Habitat Alterations color.gif 83 84
Algal Growth color.gif 72 79
Trash color.gif 72 76
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: 49,622 TMDLs; 52,652 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 287
Alaska color.gif 53
American Samoa color.gif 2
Arizona color.gif 86
Arkansas color.gif 271
California color.gif 1,568
Colorado color.gif 988
Connecticut color.gif 325
Delaware color.gif 576
District Of Columbia color.gif 371
Florida color.gif 863
Georgia color.gif 1,662
Guam color.gif 18
Hawaii color.gif 64
Idaho color.gif 1,949
Illinois color.gif 341
Indiana color.gif 1,045
Iowa color.gif 188
Kansas color.gif 2,982
Kentucky color.gif 251
Louisiana color.gif 750
Maine color.gif 337
Maryland color.gif 767
Massachusetts color.gif 576
Michigan color.gif 237
Minnesota color.gif 1,384
Mississippi color.gif 1,430
Missouri color.gif 288
Montana color.gif 1,114
Nebraska color.gif 108
Nevada color.gif 64
New Hampshire color.gif 6,006
New Jersey color.gif 616
New Mexico color.gif 311
New York color.gif 663
North Carolina color.gif 220
North Dakota color.gif 123
Ohio color.gif 1,594
Oklahoma color.gif 611
Oregon color.gif 1,241
Pennsylvania color.gif 7,058
Puerto Rico color.gif 321
Rhode Island color.gif 190
South Carolina color.gif 485
South Dakota color.gif 321
Tennessee color.gif 1,210
Texas color.gif 224
Utah color.gif 308
Vermont color.gif 119
Virgin Islands color.gif 66
Virginia color.gif 1,393
Washington color.gif 1,468
West Virginia color.gif 3,529
Wisconsin color.gif 247
Wyoming color.gif 353

Total: 49,622 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 122 123
1997 color.gif 337 351
1998 color.gif 402 408
1999 color.gif 330 373
2000 color.gif 1,556 1,581
2001 color.gif 2,577 2,613
2002 color.gif 2,737 2,820
2003 color.gif 3,002 3,278
2004 color.gif 3,374 3,631
2005 color.gif 4,312 4,630
2006 color.gif 4,209 4,560
2007 color.gif 4,321 4,650
2008 color.gif 9,264 9,547
2009 color.gif 4,398 4,627
2010 color.gif 2,564 2,703
2011 color.gif 2,819 3,112
2012 color.gif 2,880 3,154
2013 color.gif 418 491

Total: 49,622 TMDLs; 52,652 Causes of Impairment Addressed

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Status of Available Data Used in This Report

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