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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 44
Arizona color.gif 79
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 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 480
Kansas color.gif 1,372
Kentucky color.gif 1,300
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 584
N. Mariana Islands color.gif 24
Nebraska color.gif 330
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 1,270
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 155
Tennessee color.gif 1,028
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: 42,709 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 10,951
Nutrients color.gif 7,697
Metals (other than Mercury) color.gif 7,143
Organic Enrichment/Oxygen Depletion color.gif 6,713
Sediment color.gif 6,626
Polychlorinated Biphenyls (PCBs) color.gif 5,760
Mercury color.gif 4,896
pH/Acidity/Caustic Conditions color.gif 4,326
Cause Unknown - Impaired Biota color.gif 3,704
Temperature color.gif 3,241
Turbidity color.gif 2,914
Pesticides color.gif 1,990
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 1,934
Algal Growth color.gif 1,292
Cause Unknown color.gif 1,199
Habitat Alterations color.gif 811
Dioxins color.gif 627
Total Toxics color.gif 515
Other Cause color.gif 494
Toxic Organics color.gif 421
Ammonia color.gif 405
Toxic Inorganics color.gif 376
Flow Alteration(s) color.gif 239
Oil and Grease color.gif 190
Taste, Color and Odor color.gif 142
Nuisance Exotic Species color.gif 119
Fish Consumption Advisory color.gif 97
Noxious Aquatic Plants color.gif 89
Biotoxins color.gif 87
Trash color.gif 71
Cause Unknown - Fish Kills color.gif 69
Radiation color.gif 52
Chlorine color.gif 50
Nuisance Native Species color.gif 3

Total: 75,243 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 12,331 12,625
Metals (other than Mercury) color.gif 9,395 9,584
Mercury color.gif 7,153 7,181
Nutrients color.gif 5,766 6,922
Sediment color.gif 3,881 4,511
Temperature color.gif 2,249 2,259
Organic Enrichment/Oxygen Depletion color.gif 2,127 2,246
pH/Acidity/Caustic Conditions color.gif 1,927 1,986
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 1,644 1,702
Turbidity color.gif 1,486 1,691
Pesticides color.gif 1,207 1,306
Ammonia color.gif 1,106 1,170
Polychlorinated Biphenyls (PCBs) color.gif 516 537
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 87 95
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: 52,329 TMDLs; 55,394 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 317
California color.gif 1,637
Colorado color.gif 1,005
Connecticut color.gif 372
Delaware color.gif 579
District Of Columbia color.gif 371
Florida color.gif 1,063
Georgia color.gif 1,722
Guam color.gif 18
Hawaii color.gif 64
Idaho color.gif 2,109
Illinois color.gif 427
Indiana color.gif 1,123
Iowa color.gif 201
Kansas color.gif 3,181
Kentucky color.gif 302
Louisiana color.gif 750
Maine color.gif 337
Maryland color.gif 795
Massachusetts color.gif 581
Michigan color.gif 238
Minnesota color.gif 1,590
Mississippi color.gif 1,438
Missouri color.gif 288
Montana color.gif 1,328
Nebraska color.gif 143
Nevada color.gif 67
New Hampshire color.gif 6,050
New Jersey color.gif 616
New Mexico color.gif 322
New York color.gif 666
North Carolina color.gif 264
North Dakota color.gif 136
Ohio color.gif 1,703
Oklahoma color.gif 641
Oregon color.gif 1,241
Pennsylvania color.gif 7,138
Puerto Rico color.gif 321
Rhode Island color.gif 210
South Carolina color.gif 516
South Dakota color.gif 329
Tennessee color.gif 1,240
Texas color.gif 247
Utah color.gif 311
Vermont color.gif 119
Virgin Islands color.gif 66
Virginia color.gif 1,454
Washington color.gif 1,486
West Virginia color.gif 4,123
Wisconsin color.gif 247
Wyoming color.gif 386

Total: 52,329 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 1,556 1,581
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 4,208 4,559
2007 color.gif 4,321 4,651
2008 color.gif 9,262 9,545
2009 color.gif 4,399 4,625
2010 color.gif 2,572 2,708
2011 color.gif 2,830 3,113
2012 color.gif 2,883 3,151
2013 color.gif 2,359 2,447
2014 color.gif 716 765

Total: 52,329 TMDLs; 55,394 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 2010 2010
Arizona 2008 2008
Arkansas 2008 2008
California 2010 2010
Colorado 2010 2010
Connecticut 2012 2012
Delaware 2006 2006
District Of Columbia 2010 2010
Florida 2010 2010
Georgia 2010 2010
Guam 2010 2010
Hawaii 2006 2006
Idaho 2010 2010
Illinois 2010 2006
Indiana 2010 2008
Iowa 2012 2012
Kansas 2014 2014
Kentucky 2010 2010
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 2012 2012
N. Mariana Islands 2010 2010
Nebraska 2014 2012
Nevada 2010 2010
New Hampshire 2010 2010
New Jersey 2010 2010
New Mexico 2012 2012
New York 2012 2012
North Carolina 2010 2010
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 2010 2012
Tennessee 2010 2010
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