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• Impaired 

Waters Listed 

by State

• Causes of 

Impairment for 

303(d) Listed 

Waters

• Cumulative 

TMDLs by 

Pollutant

• Approved 

TMDLs by 

State

• Cumulative 

Number of 

TMDLs

• Status of 

Available Data 

Used in This 

Report

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Information:

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Choose a state or territory from the map below or the 

list to the right. Alabama  GO

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.

National Summary of Impaired Waters and 

TMDL Information

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Impaired Waters Listed By State

Description of this table

State Name Number of Waters on 303(d) List

Alabama 220

Alaska 35

American Samoa 45

Arizona 90

Arkansas 225

California 1,052

Colorado 293

Connecticut 286

Delaware 101

District Of Columbia 36

Florida 2,292

Georgia 242

Guam 47

Hawaii 352

Idaho 741

Illinois 1,057

Indiana 1,836

Iowa 480

Kansas 1,372

Kentucky 1,433

Louisiana 236

Maine 113

Maryland 337

Massachusetts 720

Michigan 2,584

Minnesota 1,592

Mississippi 261

Missouri 270

Montana 480

N. Mariana Islands 24

Nebraska 342

Nevada 210

New Hampshire 1,449

New Jersey 710

New Mexico 237

New York 1,543

North Carolina 1,152

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North Dakota 217

Ohio 267

Oklahoma 635

Oregon 1,397

Pennsylvania 6,957

Puerto Rico 195

Rhode Island 121

South Carolina 907

South Dakota 166

Tennessee 1,012

Texas 719

Utah 156

Vermont 101

Virgin Islands 87

Virginia 1,490

Washington 2,420

West Virginia 1,097

Wisconsin 663

Wyoming 107

Total: 43,209 impaired waters

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.

Cause of Impairment Group Name Number of Causes of Impairment Reported

Pathogens 10,676

Nutrients 7,902

Metals (other than Mercury) 7,060

Organic Enrichment/Oxygen Depletion 6,707

Sediment 6,466

Polychlorinated Biphenyls (PCBs) 6,181

Mercury 4,565

pH/Acidity/Caustic Conditions 4,318

Cause Unknown - Impaired Biota 4,073

Temperature 3,127

Turbidity 2,912

Salinity/Total Dissolved 

Solids/Chlorides/Sulfates 1,911

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Pesticides 1,796

Algal Growth 1,284

Cause Unknown 1,156

Habitat Alterations 860

Dioxins 561

Total Toxics 521

Toxic Organics 457

Other Cause 453

Ammonia 420

Toxic Inorganics 373

Flow Alteration(s) 210

Oil and Grease 189

Nuisance Exotic Species 119

Taste, Color and Odor 102

Fish Consumption Advisory 98

Biotoxins 82

Trash 70

Noxious Aquatic Plants 68

Cause Unknown - Fish Kills 64

Chlorine 59

Radiation 52

Nuisance Native Species 4

Total: 74,896 Causes of Impairment

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.

Pollutant Group Number of 

TMDLs

Number of 

Causes of

Impairment 

Addressed

Mercury 21,545 21,575

Pathogens 13,263 13,572

Metals (other than 

Mercury) 9,955 10,153

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Nutrients 6,154 7,520

Sediment 3,943 4,593

Temperature 2,305 2,315

Organic 

Enrichment/Oxygen 

Depletion

2,191 2,315

pH/Acidity/Caustic 

Conditions 1,958 2,017

Salinity/Total Dissolved 

Solids/Chlorides/Sulfates 1,715 1,773

Turbidity 1,603 1,829

Pesticides 1,351 1,514

Ammonia 1,131 1,230

Polychlorinated Biphenyls 

(PCBs) 500 520

Chlorine 335 341

Other Cause 268 323

Toxic Inorganics 206 206

Toxic Organics 158 199

Cause Unknown - Impaired 

Biota 128 132

Total Toxics 120 130

Algal Growth 95 103

Habitat Alterations 83 84

Trash 75 75

Dioxins 27 28

Noxious Aquatic Plants 21 22

Radiation 19 22

Oil and Grease 14 14

Cause Unknown 7 7

Nuisance Exotic Species 3 6

Fish Consumption 

Advisory 2 2

Total: 69,175 TMDLs; 72,620 Causes of Impairment Addressed

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.

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State Name Number of TMDLs

Alabama 305

Alaska 60

American Samoa 43

Arizona 88

Arkansas 318

California 2,013

Colorado 1,016

Connecticut 407

Delaware 581

District Of Columbia 385

Florida 2,246

Georgia 1,700

Guam 43

Hawaii 65

Idaho 2,187

Illinois 429

Indiana 1,305

Iowa 217

Kansas 3,335

Kentucky 345

Louisiana 750

Maine 341

Maryland 830

Massachusetts 607

Michigan 238

Minnesota 1,802

Mississippi 1,440

Missouri 288

Montana 1,444

Nebraska 171

Nevada 67

New Hampshire 6,055

New Jersey 616

New Mexico 344

New York 719

North Carolina 13,443

North Dakota 137

Ohio 1,761

Oklahoma 704

Oregon 1,241

Pennsylvania 7,152

Puerto Rico 321

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Rhode Island 217

South Carolina 524

South Dakota 329

Tennessee 1,276

Texas 268

Utah 319

Vermont 119

Virgin Islands 66

Virginia 1,490

Washington 1,500

West Virginia 4,867

Wisconsin 247

Wyoming 394

Total: 69,175 TMDLs

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.

Fiscal 

Year Number of TMDLs

Number of 

Causes of

Impairment 

Addressed

1996 135 136

1997 337 351

1998 402 408

1999 330 373

2000 1,555 1,580

2001 2,581 2,617

2002 2,735 2,815

2003 3,008 3,281

2004 3,392 3,650

2005 4,319 4,634

2006 4,205 4,556

2007 4,321 4,651

2008 9,264 9,546

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2009 4,399 4,623

2010 2,572 2,708

2011 2,830 3,113

2012 2,883 3,151

2013 15,534 15,624

2014 3,338 3,511

2015 946 1,068

2016 89 224

Total: 69,175 TMDLs; 72,620 Causes of Impairment Addressed

Status of Available Data Used in This Report

Description of this table

State Name Assessed Waters Report YearImpaired Waters Report Year

Alabama 2014 2014

Alaska 2010 2010

American Samoa 2014 2014

Arizona 2010 2010

Arkansas 2008 2008

California 2012 2012

Colorado 2012 2012

Connecticut 2014 2014

Delaware 2006 2006

District Of Columbia2014 2014

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 2012 2012

Massachusetts 2012 2012

Michigan 2010 2010

Minnesota 2012 2012

Mississippi 2014 2014

Missouri 2014 2014

Montana 2014 2014

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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 2014 2014

South Carolina 2012 2012

South Dakota 2014 2014

Tennessee 2012 2012

Texas 2010 2010

Utah 2010 2010

Vermont 2014 2014

Virgin Islands 2012 2012

Virginia 2014 2012

Washington 2008 2008

West Virginia 2010 2010

Wisconsin 2006 2008

Wyoming 2012 2012

TMDL Document Search

Full Text Search of TMDL Documents

January 11, 2016

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