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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 200
Alaska color.gif 33
American Samoa color.gif 42
Arizona color.gif 68
Arkansas color.gif 189
California color.gif 691
Colorado color.gif 200
Connecticut color.gif 408
Delaware color.gif 101
District Of Columbia color.gif 27
Florida color.gif 827
Georgia color.gif 281
Guam color.gif 50
Hawaii color.gif 311
Idaho color.gif 1,056
Illinois color.gif 1,058
Indiana color.gif 1,836
Iowa color.gif 0
Kansas color.gif 1,333
Kentucky color.gif 1,089
Louisiana color.gif 250
Maine color.gif 157
Maryland color.gif 501
Massachusetts color.gif 837
Michigan color.gif 2,352
Minnesota color.gif 1,144
Mississippi color.gif 197
Missouri color.gif 0
Montana color.gif 677
N. Mariana Islands color.gif 71
Nebraska color.gif 177
Nevada color.gif 129
New Hampshire color.gif 5,211
New Jersey color.gif 835
New Mexico color.gif 188
New York color.gif 491
North Carolina color.gif 902
North Dakota color.gif 247
Ohio color.gif 267
Oklahoma color.gif 681
Oregon color.gif 1,397
Pennsylvania color.gif 6,957
Puerto Rico color.gif 166
Rhode Island color.gif 141
South Carolina color.gif 1,060
South Dakota color.gif 168
Tennessee color.gif 900
Texas color.gif 651
Utah color.gif 118
Vermont color.gif 143
Virgin Islands color.gif 77
Virginia color.gif 2,534
Washington color.gif 1,714
West Virginia color.gif 1,271
Wisconsin color.gif 593
Wyoming color.gif 106

Total: 43,110 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 10,136
Mercury color.gif 8,862
Metals (other than Mercury) color.gif 7,250
Nutrients color.gif 6,833
Sediment color.gif 6,263
Polychlorinated Biphenyls (PCBs) color.gif 6,096
Organic Enrichment/Oxygen Depletion color.gif 5,773
pH/Acidity/Caustic Conditions color.gif 3,713
Cause Unknown - Impaired Biota color.gif 3,167
Turbidity color.gif 3,043
Temperature color.gif 2,791
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 1,628
Pesticides color.gif 1,600
Cause Unknown color.gif 1,164
Noxious Aquatic Plants color.gif 982
Habitat Alterations color.gif 688
Dioxins color.gif 552
Algal Growth color.gif 494
Toxic Inorganics color.gif 333
Toxic Organics color.gif 328
Ammonia color.gif 324
Total Toxics color.gif 312
Other Cause color.gif 189
Taste, Color and Odor color.gif 144
Oil and Grease color.gif 138
Flow Alteration(s) color.gif 114
Fish Consumption Advisory color.gif 57
Trash color.gif 56
Chlorine color.gif 31
Nuisance Exotic Species color.gif 28
Radiation color.gif 24
Cause Unknown - Fish Kills color.gif 9
Nuisance Native Species color.gif 6

Total: 73,128 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 6,878 7,100
Mercury color.gif 6,671 6,704
Metals (other than Mercury) color.gif 6,277 6,395
Nutrients color.gif 4,217 5,049
Sediment color.gif 2,952 3,437
Organic Enrichment/Oxygen Depletion color.gif 1,752 1,826
Temperature color.gif 1,522 1,529
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 1,507 1,548
pH/Acidity/Caustic Conditions color.gif 1,489 1,524
Ammonia color.gif 1,028 1,078
Pesticides color.gif 986 1,046
Turbidity color.gif 869 992
Polychlorinated Biphenyls (PCBs) color.gif 353 367
Chlorine color.gif 336 341
Other Cause color.gif 205 222
Toxic Inorganics color.gif 186 186
Cause Unknown - Impaired Biota color.gif 149 153
Toxic Organics color.gif 124 124
Total Toxics color.gif 92 100
Habitat Alterations color.gif 83 84
Algal Growth color.gif 65 69
Trash color.gif 65 68
Dioxins color.gif 24 25
Noxious Aquatic Plants color.gif 21 22
Radiation color.gif 21 22
Oil and Grease color.gif 12 13
Cause Unknown color.gif 5 5
Fish Consumption Advisory color.gif 2 2
Nuisance Exotic Species color.gif 2 2

Total: 37,893 TMDLs; 40,033 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 250
Alaska color.gif 43
American Samoa color.gif 2
Arizona color.gif 73
Arkansas color.gif 224
California color.gif 952
Colorado color.gif 928
Connecticut color.gif 109
Delaware color.gif 558
District Of Columbia color.gif 360
Florida color.gif 581
Georgia color.gif 1,439
Guam color.gif 1
Hawaii color.gif 49
Idaho color.gif 1,611
Illinois color.gif 280
Indiana color.gif 688
Iowa color.gif 132
Kansas color.gif 2,708
Kentucky color.gif 83
Louisiana color.gif 665
Maine color.gif 87
Maryland color.gif 605
Massachusetts color.gif 373
Michigan color.gif 149
Minnesota color.gif 1,162
Mississippi color.gif 1,165
Missouri color.gif 137
Montana color.gif 495
Nebraska color.gif 75
Nevada color.gif 58
New Hampshire color.gif 5,509
New Jersey color.gif 476
New Mexico color.gif 204
New York color.gif 637
North Carolina color.gif 139
North Dakota color.gif 46
Ohio color.gif 899
Oklahoma color.gif 191
Oregon color.gif 1,035
Pennsylvania color.gif 5,505
Puerto Rico color.gif 53
Rhode Island color.gif 102
South Carolina color.gif 425
South Dakota color.gif 265
Tennessee color.gif 1,012
Texas color.gif 154
Utah color.gif 301
Vermont color.gif 94
Virgin Islands color.gif 29
Virginia color.gif 962
Washington color.gif 1,058
West Virginia color.gif 2,316
Wisconsin color.gif 97
Wyoming color.gif 342

Total: 37,893 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 338 352
1998 color.gif 403 409
1999 color.gif 347 395
2000 color.gif 1,551 1,574
2001 color.gif 2,571 2,607
2002 color.gif 2,749 2,824
2003 color.gif 3,045 3,322
2004 color.gif 3,377 3,642
2005 color.gif 4,281 4,602
2006 color.gif 4,202 4,554
2007 color.gif 4,319 4,650
2008 color.gif 9,199 9,479
2009 color.gif 1,389 1,500

Total: 37,893 TMDLs; 40,033 Causes of Impairment Addressed

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Status of Available Data Used in This Report

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


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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