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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 190
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 279
Delaware color.gif 101
District Of Columbia color.gif 25
Florida color.gif 827
Georgia color.gif 930
Guam color.gif 49
Hawaii color.gif 244
Idaho color.gif 1,392
Illinois color.gif 1,058
Indiana color.gif 1,591
Iowa color.gif 213
Kansas color.gif 1,101
Kentucky color.gif 736
Louisiana color.gif 250
Maine color.gif 193
Maryland color.gif 501
Massachusetts color.gif 837
Michigan color.gif 430
Minnesota color.gif 1,734
Mississippi color.gif 378
Missouri color.gif 32
Montana color.gif 677
N. Mariana Islands color.gif 0
Nebraska color.gif 150
Nevada color.gif 129
New Hampshire color.gif 5,211
New Jersey color.gif 835
New Mexico color.gif 188
New York color.gif 610
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 127
Rhode Island color.gif 166
South Carolina color.gif 915
South Dakota color.gif 168
Tennessee color.gif 960
Texas color.gif 675
Utah color.gif 118
Vermont color.gif 143
Virgin Islands color.gif 66
Virginia color.gif 2,172
Washington color.gif 1,714
West Virginia color.gif 1,271
Wisconsin color.gif 593
Wyoming color.gif 125

Total: 41,778 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 10,269
Mercury color.gif 9,129
Metals (other than Mercury) color.gif 6,919
Sediment color.gif 6,398
Nutrients color.gif 5,962
Organic Enrichment/Oxygen Depletion color.gif 5,665
pH/Acidity/Caustic Conditions color.gif 3,823
Cause Unknown - Impaired Biota color.gif 3,286
Polychlorinated Biphenyls (PCBs) color.gif 3,074
Temperature color.gif 3,013
Turbidity color.gif 2,447
Pesticides color.gif 1,612
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 1,551
Cause Unknown color.gif 1,375
Habitat Alterations color.gif 983
Noxious Aquatic Plants color.gif 889
Algal Growth color.gif 455
Dioxins color.gif 398
Toxic Organics color.gif 374
Toxic Inorganics color.gif 344
Ammonia color.gif 317
Total Toxics color.gif 313
Flow Alteration(s) color.gif 229
Oil and Grease color.gif 135
Other Cause color.gif 132
Taste, Color and Odor color.gif 106
Fish Consumption Advisory color.gif 70
Trash color.gif 56
Chlorine color.gif 49
Radiation color.gif 34
Nuisance Exotic Species color.gif 33
Cause Unknown - Fish Kills color.gif 8
Nuisance Native Species color.gif 6

Total: 69,454 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 6,671 6,704
Pathogens color.gif 6,554 6,766
Metals (other than Mercury) color.gif 6,045 6,160
Nutrients color.gif 4,126 4,831
Sediment color.gif 2,875 3,346
Organic Enrichment/Oxygen Depletion color.gif 1,773 1,801
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 1,503 1,540
pH/Acidity/Caustic Conditions color.gif 1,428 1,458
Temperature color.gif 1,348 1,354
Ammonia color.gif 1,068 1,076
Pesticides color.gif 982 1,039
Turbidity color.gif 875 945
Polychlorinated Biphenyls (PCBs) color.gif 351 364
Chlorine color.gif 342 341
Other Cause color.gif 204 219
Toxic Inorganics color.gif 186 186
Cause Unknown - Impaired Biota color.gif 132 132
Toxic Organics color.gif 124 124
Total Toxics color.gif 93 100
Habitat Alterations color.gif 83 84
Algal Growth color.gif 76 67
Trash color.gif 56 59
Dioxins color.gif 40 22
Noxious Aquatic Plants color.gif 21 22
Radiation color.gif 21 22
Oil and Grease color.gif 12 13
Fish Consumption Advisory color.gif 2 2
Nuisance Exotic Species color.gif 2 2

Total: 36,735 TMDLs; 38,779 Causes of Impairment Addressed

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Approved TMDLs By State

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 35
American Samoa color.gif 2
Arizona color.gif 73
Arkansas color.gif 222
California color.gif 934
Colorado color.gif 928
Connecticut color.gif 109
Delaware color.gif 557
District Of Columbia color.gif 360
Florida color.gif 548
Georgia color.gif 1,439
Guam color.gif 1
Hawaii color.gif 49
Idaho color.gif 1,529
Illinois color.gif 280
Indiana color.gif 665
Iowa color.gif 123
Kansas color.gif 2,708
Kentucky color.gif 83
Louisiana color.gif 662
Maine color.gif 87
Maryland color.gif 586
Massachusetts color.gif 313
Michigan color.gif 142
Minnesota color.gif 1,117
Mississippi color.gif 1,165
Missouri color.gif 136
Montana color.gif 488
Nebraska color.gif 75
Nevada color.gif 58
New Hampshire color.gif 5,505
New Jersey color.gif 469
New Mexico color.gif 196
New York color.gif 634
North Carolina color.gif 125
North Dakota color.gif 45
Ohio color.gif 819
Oklahoma color.gif 191
Oregon color.gif 888
Pennsylvania color.gif 5,174
Puerto Rico color.gif 53
Rhode Island color.gif 102
South Carolina color.gif 425
South Dakota color.gif 265
Tennessee color.gif 971
Texas color.gif 105
Utah color.gif 301
Vermont color.gif 90
Virgin Islands color.gif 29
Virginia color.gif 913
Washington color.gif 1,058
West Virginia color.gif 2,218
Wisconsin color.gif 93
Wyoming color.gif 342

Total: 36,735 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 112 113
1997 color.gif 341 355
1998 color.gif 403 409
1999 color.gif 347 395
2000 color.gif 1,550 1,573
2001 color.gif 2,572 2,608
2002 color.gif 2,746 2,822
2003 color.gif 3,036 3,313
2004 color.gif 3,383 3,648
2005 color.gif 4,281 4,602
2006 color.gif 4,203 4,552
2007 color.gif 4,310 4,641
2008 color.gif 9,181 9,460
2009 color.gif 270 288

Total: 36,735 TMDLs; 38,779 Causes of Impairment Addressed

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Status of Available Data Used in This Report

Description of this table
Alabama 2006 2006
Alaska 2006 2006
American Samoa Not included in report 2008
Arizona 2004 2004
Arkansas 2004 2004
California 2004 2006
Colorado 2008 2008
Connecticut 2006 2006
Delaware 2006 2006
District Of Columbia 2006 2006
Florida 2002 2002
Georgia 2006 2006
Guam 2006 2006
Hawaii 2006 2004
Idaho 2002 2002
Illinois 2006 2006
Indiana 2006 2006
Iowa 2006 2004
Kansas 2006 2004
Kentucky 2006 2004
Louisiana 2006 2006
Maine 2006 2006
Maryland 2002 2006
Massachusetts 2006 2006
Michigan 2006 2006
Minnesota 2006 2006
Mississippi 2006 2006
Missouri 2006 2006
Montana 2006 2006
N. Mariana Islands Not included in report 2006
Nebraska 2006 2004
Nevada 2006 2004
New Hampshire 2006 2006
New Jersey 2006 2006
New Mexico 2006 2004
New York 2006 2006
North Carolina 2006 2006
North Dakota 2008 2008
Ohio 2006 2006
Oklahoma 2006 2006
Oregon 2006 2006
Pennsylvania 2006 2004
Puerto Rico 2006 2006
Rhode Island 2006 2006
South Carolina 2006 2006
South Dakota 2008 2008
Tennessee 2006 2006
Texas 2006 2006
Utah 2006 2006
Vermont 2006 2006
Virgin Islands 2006 2006
Virginia 2006 2006
Washington 2004 2004
West Virginia 2006 2006
Wisconsin 2006 2006
Wyoming 2006 2006


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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