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Region 4 Summary of State Information

Map of the Region 4 Connecticut Maine Massachusetts New Hampshire Rhode Island Vermont New Jersey New York Puerto Rico U.S. Virgin Islands Delaware District of Columbia Maryland Pennsylvania Virginia West Virginia Alabama Florida Georgia Kentucky Mississippi North Carolina South Carolina Tennessee Illinois Indiana Michigan Minnesota Ohio Wisconsin Arkansas Louisiana New Mexico Oklahoma Texas Iowa Kansas Missouri Nebraska Colorado Montana North Dakota South Dakota Utah Wyoming Arizona California Hawaii Nevada Alaska Idaho Oregon Washington

Depicted below are regional 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.


Frequent Questions


Assessed Waters of Region 4

Incomplete state reported information may lead to discrepancies and/or missing information in these reports.

Description of this table
  Size of Water
Rivers and
Streams (Miles)		 Lakes, Reservoirs,
and Ponds (Acres)		 Bays and
Estuaries
(Square Miles)		 Coastal
Shoreline
(Miles)		 Ocean and
Near Coastal
(Square Miles)		 Wetlands
(Acres)
   Good Waters 45,489 1,323,039 434 178 2 632,056
   Threatened Waters 47
   Impaired Waters 39,970 615,908 671 382 201 110,000
Total Assessed Waters 85,506 1,938,946 1,104 560 203 742,056
Total Waters 460,889 4,986,160 10,183 245 Unavailable 7,175,000
Percent of Waters Assessed 18.6 38.9 10.8 228.7 Unavailable 10.3

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Summary of Water Quality Assessments for Each Waterbody Type


Region 4
Water Quality Attainment in Assessed Rivers and Streams

Description of this table
Assessed Status Miles
Assessed 85,506
Unassessed 375,383
Total Miles 460,889







arrow pointing right 		Description of this table
Attainment Status Miles
Good 45,489
Threatened 47
Impaired 39,970
Total Miles Assessed 85,506

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Region 4
Designated Use Support in Assessed Rivers and Streams*

* Waters assessed for more than one designated use are included in multiple designated use groups below.

Description of this table
Designated Use Group Miles Assessed Percent Good Percent Threatened Percent Impaired % Good
% Threatened
% Impaired
Fish, Shellfish, and Wildlife Protection and Propagation Fish, Shellfish, And Wildlife Protection And Propagation 7,080 49.5 .0 50.5 color.gifcolor.gif
Recreation Recreation 164 100.0 .0 .0 color.gif

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Region 4
Causes of Impairment in Assessed Rivers and Streams

Description of this table
Cause of Impairment Group Miles
Threatened or
Impaired
Pathogens color.gif 17,283
Sediment color.gif 11,126
Cause Unknown - Impaired Biota color.gif 7,663
Habitat Alterations color.gif 6,160
Organic Enrichment/Oxygen Depletion color.gif 6,080
Nutrients color.gif 5,030
Mercury color.gif 3,149
Metals (other than Mercury) color.gif 1,604
pH/Acidity/Caustic Conditions color.gif 1,356
Polychlorinated Biphenyls (PCBs) color.gif 936
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 917
Flow Alteration(s) color.gif 851
Cause Unknown color.gif 838
Turbidity color.gif 732
Pesticides color.gif 482
Ammonia color.gif 283
Dioxins color.gif 263
Other Cause color.gif 254
Temperature color.gif 173
Toxic Organics color.gif 158
Algal Growth color.gif 120
Total Toxics color.gif 101
Oil and Grease color.gif 76
Toxic Inorganics color.gif 64
Chlorine color.gif 57
Nuisance Exotic Species color.gif 55
Radiation color.gif 24
Taste, Color and Odor color.gif 12
Noxious Aquatic Plants color.gif 9
Nuisance Native Species color.gif 7

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Region 4
Probable Sources of Impairments in Assessed Rivers and Streams

Description of this table
Probable Source Group Miles
Threatened or
Impaired
Agriculture color.gif 10,695
Unknown color.gif 8,310
Urban-Related Runoff/Stormwater color.gif 6,117
Unspecified Nonpoint Source color.gif 5,627
Hydromodification color.gif 5,171
Municipal Dishcarges/Sewage color.gif 3,415
Resource Extraction color.gif 2,298
Habitat Alterations (Not Directly Related To Hydromodification) color.gif 1,866
Construction color.gif 1,606
Industrial color.gif 1,010
Legacy/Historical Pollutants color.gif 435
Other color.gif 396
Silviculture (Forestry) color.gif 366
Atmospheric Deposition color.gif 310
Spills/Dumping color.gif 205
Land Application/Waste Sites/Tanks color.gif 155
Recreational Boating And Marinas color.gif 57
Recreation And Tourism (Non-Boating) color.gif 57
Natural/Wildlife color.gif 41
Military Bases color.gif 38
Aquaculture color.gif 3

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Region 4
Water Quality Attainment in Assessed Lakes, Reservoirs, and Ponds

Description of this table
Assessed Status Acres
Assessed 1,938,946
Unassessed 3,047,214
Total Acres 4,986,160







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Attainment Status Acres
Good 1,323,039
Threatened 0
Impaired 615,908
Total Acres Assessed 1,938,946

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Region 4
Designated Use Support in Assessed Lakes, Reservoirs, and Ponds*

* Waters assessed for more than one designated use are included in multiple designated use groups below.

Description of this table
Designated Use Group Acres Assessed Percent Good Percent Threatened Percent Impaired % Good
% Threatened
% Impaired
Fish, Shellfish, and Wildlife Protection and Propagation Fish, Shellfish, And Wildlife Protection And Propagation 107,080 45.5 .0 54.5 color.gifcolor.gif
Recreation Recreation 6,016 100.0 .0 .0 color.gif

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Region 4
Causes of Impairment in Assessed Lakes, Reservoirs, and Ponds

Description of this table
Cause of Impairment Group Acres
Threatened or
Impaired
Polychlorinated Biphenyls (PCBs) color.gif 254,126
Mercury color.gif 225,800
Nutrients color.gif 115,898
Organic Enrichment/Oxygen Depletion color.gif 94,181
Algal Growth color.gif 51,863
pH/Acidity/Caustic Conditions color.gif 35,761
Sediment color.gif 23,333
Temperature color.gif 21,109
Pesticides color.gif 15,894
Turbidity color.gif 13,814
Dioxins color.gif 11,892
Flow Alteration(s) color.gif 11,444
Nuisance Native Species color.gif 9,691
Metals (other than Mercury) color.gif 8,263
Other Cause color.gif 3,864
Pathogens color.gif 2,414
Cause Unknown - Impaired Biota color.gif 1,146
Noxious Aquatic Plants color.gif 612
Taste, Color and Odor color.gif 544
Ammonia color.gif 424
Cause Unknown color.gif 43

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Region 4
Probable Sources of Impairments in Assessed Lakes, Reservoirs, and Ponds

Description of this table
Probable Source Group Acres
Threatened or
Impaired
Urban-Related Runoff/Stormwater color.gif 140,446
Atmospheric Deposition color.gif 131,519
Legacy/Historical Pollutants color.gif 130,150
Unspecified Nonpoint Source color.gif 73,603
Unknown color.gif 73,583
Other color.gif 67,853
Hydromodification color.gif 61,218
Industrial color.gif 52,617
Agriculture color.gif 30,690
Municipal Dishcarges/Sewage color.gif 21,172
Natural/Wildlife color.gif 20,953
Habitat Alterations (Not Directly Related To Hydromodification) color.gif 11,462
Construction color.gif 10,950
Resource Extraction color.gif 5,706
Spills/Dumping color.gif 412
Recreation And Tourism (Non-Boating) color.gif 78

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Region 4
Water Quality Attainment in Assessed Bays and Estuaries

Description of this table
Assessed Status Square Miles
Assessed 1,104
Unassessed 9,079
Total Square Miles 10,183







arrow pointing right 		Description of this table
Attainment Status Square Miles
Good 434
Threatened 0
Impaired 671
Total Square Miles Assessed 1,104

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Region 4
Designated Use Support in Assessed Bays and Estuaries*

* Waters assessed for more than one designated use are included in multiple designated use groups below.

Description of this table
Designated Use Group Square Miles Assessed Percent Good Percent Threatened Percent Impaired % Good
% Threatened
% Impaired
Recreation Recreation 6 100.0 .0 .0 color.gif

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Region 4
Causes of Impairment in Assessed Bays and Estuaries

Description of this table
Cause of Impairment Group Square Miles
Threatened or
Impaired
Pathogens color.gif 644
Organic Enrichment/Oxygen Depletion color.gif 20
Metals (other than Mercury) color.gif 5
Turbidity color.gif 4
Ammonia color.gif 2
pH/Acidity/Caustic Conditions color.gif 1
Mercury color.gif 0

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Region 4
Probable Sources of Impairments in Assessed Bays and Estuaries

Description of this table
Probable Source Group Square Miles
Threatened or
Impaired
Urban-Related Runoff/Stormwater color.gif 390
Municipal Dishcarges/Sewage color.gif 172
Industrial color.gif 14
Unspecified Nonpoint Source color.gif 10
Unknown color.gif 1

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Region 4
Water Quality Attainment in Assessed Coastal Shoreline

Description of this table
Assessed Status Miles
Assessed 560
Unassessed -315
Total Miles 245







arrow pointing right 		Description of this table
Attainment Status Miles
Good 178
Threatened 0
Impaired 382
Total Miles Assessed 560

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Region 4
Designated Use Support in Assessed Coastal Shoreline*

* Waters assessed for more than one designated use are included in multiple designated use groups below.

Description of this table
Designated Use Group Miles Assessed Percent Good Percent Threatened Percent Impaired % Good
% Threatened
% Impaired
Fish, Shellfish, and Wildlife Protection and Propagation Fish, Shellfish, And Wildlife Protection And Propagation 322 .0 .0 100.0 color.gif

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Region 4
Causes of Impairment in Assessed Coastal Shoreline

Description of this table
Cause of Impairment Group Miles
Threatened or
Impaired
Mercury color.gif 330
Metals (other than Mercury) color.gif 93
Organic Enrichment/Oxygen Depletion color.gif 32
Other Cause color.gif 30
Polychlorinated Biphenyls (PCBs) color.gif 26
Pathogens color.gif 20
Pesticides color.gif 4

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Region 4
Probable Sources of Impairments in Assessed Coastal Shoreline

Description of this table
Probable Source Group Miles
Threatened or
Impaired
Industrial color.gif 28
Urban-Related Runoff/Stormwater color.gif 22
Municipal Dishcarges/Sewage color.gif 21
Unspecified Nonpoint Source color.gif 12
Unknown color.gif 9

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Region 4
Water Quality Attainment in Assessed Ocean and Near Coastal

Description of this table
Pie chart not displayed because total size for Ocean and Near Coastal is unavailable.
Assessed Status Square Miles
Assessed 203
Unassessed Unavailable
Total Square Miles Unavailable







arrow pointing right 		Description of this table
Attainment Status Square Miles
Good 2
Threatened 0
Impaired 201
Total Square Miles Assessed 203

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Region 4
Designated Use Support in Assessed Ocean and Near Coastal*

No designated uses reported.

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Region 4
Causes of Impairment in Assessed Ocean and Near Coastal

Description of this table
Cause of Impairment Group Square Miles
Threatened or
Impaired
Mercury color.gif 201
Pathogens color.gif 0

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Region 4
Probable Sources of Impairments in Assessed Ocean and Near Coastal

Description of this table
Probable Source Group Square Miles
Threatened or
Impaired
Unknown color.gif 201

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Region 4
Water Quality Attainment in Assessed Wetlands

Description of this table
Assessed Status Acres
Assessed 742,056
Unassessed 6,432,944
Total Acres 7,175,000







arrow pointing right 		Description of this table
Attainment Status Acres
Good 632,056
Threatened 0
Impaired 110,000
Total Acres Assessed 742,056

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Region 4
Designated Use Support in Assessed Wetlands*

* Waters assessed for more than one designated use are included in multiple designated use groups below.

Description of this table
Designated Use Group Acres Assessed Percent Good Percent Threatened Percent Impaired % Good
% Threatened
% Impaired
Fish, Shellfish, and Wildlife Protection and Propagation Fish, Shellfish, And Wildlife Protection And Propagation 742,056 85.2 .0 14.8 color.gifcolor.gif

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Region 4
Causes of Impairment in Assessed Wetlands

Description of this table
Cause of Impairment Group Acres
Threatened or
Impaired
Pathogens color.gif 54,395
Organic Enrichment/Oxygen Depletion color.gif 7,175
pH/Acidity/Caustic Conditions color.gif 6,360
Algal Growth color.gif 2,654

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Region 4
Probable Sources of Impairments in Assessed Wetlands

No probable sources of impairments reported.

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Region 4 Causes of Impairment


Description of this table
NOTE: Click on a cause of impairment (e.g. algal growth) to see the specific state-reported causes that are grouped to make up this category.
Cause of Impairment Group Size of Assessed Waters with Listed Causes of Impairment
Rivers and
Streams (Miles)		 Lakes, Reservoirs,
and Ponds (Acres)		 Bays and
Estuaries
(Square Miles)		 Coastal
Shoreline
(Miles)		 Ocean and
Near Coastal
(Square Miles)		 Wetlands
(Acres)
Algal Growth 120 51,863       2,654
Ammonia 283 424 2      
Cause Unknown 838 43        
Cause Unknown - Impaired Biota 7,663 1,146        
Chlorine 57          
Dioxins 263 11,892        
Flow Alteration(s) 851 11,444        
Habitat Alterations 6,160          
Mercury 3,149 225,800 0 330 201  
Metals (other than Mercury) 1,604 8,263 5 93    
Noxious Aquatic Plants 9 612        
Nuisance Exotic Species 55          
Nuisance Native Species 7 9,691        
Nutrients 5,030 115,898        
Oil and Grease 76          
Organic Enrichment/Oxygen Depletion 6,080 94,181 20 32   7,175
Other Cause 254 3,864   30    
Pathogens 17,283 2,414 644 20 0 54,395
Pesticides 482 15,894   4    
pH/Acidity/Caustic Conditions 1,356 35,761 1     6,360
Polychlorinated Biphenyls (PCBs) 936 254,126   26    
Radiation 24          
Salinity/Total Dissolved Solids/Chlorides/Sulfates 917          
Sediment 11,126 23,333        
Taste, Color and Odor 12 544        
Temperature 173 21,109        
Total Toxics 101          
Toxic Inorganics 64          
Toxic Organics 158          
Turbidity 732 13,814 4      

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Region 4 Probable Sources Contributing to Impairments

Description of this table
NOTE: Click on a source of impairment (e.g. agriculture) to see the specific state-reported sources that are grouped to make up this category.
Probable Source Group Size of Assessed Waters with Probable Sources of Impairments
Rivers and
Streams (Miles)		 Lakes, Reservoirs,
and Ponds (Acres)		 Bays and
Estuaries
(Square Miles)		 Coastal
Shoreline
(Miles)		 Ocean and
Near Coastal
(Square Miles)
Agriculture 10,695 30,690      
Aquaculture 3        
Atmospheric Deposition 310 131,519      
Construction 1,606 10,950      
Habitat Alterations (Not Directly Related To Hydromodification) 1,866 11,462      
Hydromodification 5,171 61,218      
Industrial 1,010 52,617 14 28  
Land Application/Waste Sites/Tanks 155        
Legacy/Historical Pollutants 435 130,150      
Military Bases 38        
Municipal Dishcarges/Sewage 3,415 21,172 172 21  
Natural/Wildlife 41 20,953      
Other 396 67,853      
Recreation And Tourism (Non-Boating) 57 78      
Recreational Boating And Marinas 57        
Resource Extraction 2,298 5,706      
Silviculture (Forestry) 366        
Spills/Dumping 205 412      
Unknown 8,310 73,583 1 9 201
Unspecified Nonpoint Source 5,627 73,603 10 12  
Urban-Related Runoff/Stormwater 6,117 140,446 390 22  

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Region 4 Previously Impaired Waters Now Attaining All Uses

Description of this table
NOTE: Click on the underlined "Number of Waters Attaining" value for a detailed list of those waters now attaining all uses.
Cycle Attaining Number of Waters Attaining Number of Causes of
Impairment Addressed
2002 color.gif 23 24
2003 color.gif 1 1
2004 color.gif 38 39
2005 color.gif 20 26
2007 color.gif 141 171
2008 color.gif 6 7

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Region 4
Impaired Waters Listed By State

Description of this table
State Name Number of Waters on 303(d) List
Alabama color.gif 200
Florida color.gif 827
Georgia color.gif 281
Kentucky color.gif 1,089
Mississippi color.gif 197
North Carolina color.gif 902
South Carolina color.gif 1,060
Tennessee color.gif 900

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Region 4 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
Pathogens color.gif 2,115 2,134
Sediment color.gif 995 1,165
Nutrients color.gif 981 1,171
Organic Enrichment/Oxygen Depletion color.gif 536 597
Pesticides color.gif 324 336
Mercury color.gif 127 134
Metals (other than Mercury) color.gif 89 91
Polychlorinated Biphenyls (PCBs) color.gif 83 90
pH/Acidity/Caustic Conditions color.gif 70 71
Habitat Alterations color.gif 60 61
Ammonia color.gif 35 40
Total Toxics color.gif 33 41
Turbidity color.gif 24 25
Dioxins color.gif 14 15
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 10 10
Other Cause color.gif 6 6
Noxious Aquatic Plants color.gif 5 5
Toxic Organics color.gif 5 5
Chlorine color.gif 2 2
Temperature color.gif 2 2
Toxic Inorganics color.gif 2 2
Oil and Grease color.gif 1 1

Total: 5,519 TMDLs; 6,004 Causes of Impairment Addressed

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Region 4 Approved TMDLs By State

This chart includes TMDLs since October 1, 1995.

Description of this table
State Name Number of TMDLs
Alabama color.gif 265
Florida color.gif 657
Georgia color.gif 1,554
Kentucky color.gif 124
Mississippi color.gif 1,310
North Carolina color.gif 145
South Carolina color.gif 425
Tennessee color.gif 1,039

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Region 4 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 color.gif 12 12
1997 color.gif 25 27
1998 color.gif 147 147
1999 color.gif 31 31
2000 color.gif 153 155
2001 color.gif 188 207
2002 color.gif 666 674
2003 color.gif 448 517
2004 color.gif 480 501
2005 color.gif 463 505
2006 color.gif 780 875
2007 color.gif 612 670
2008 color.gif 840 919
2009 color.gif 674 764

Total: 5,519 TMDLs; 6,004 Causes of Impairment Addressed

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Status of Available Data Used in This Report

Description of this table
State Name Assessed Waters Report Year Impaired Waters Report Year
Alabama 2008 2008
Florida 2002 2002
Georgia 2008 2008
Kentucky 2008 2008
Mississippi 2008 2008
North Carolina 2006 2006
South Carolina 2008 2008
Tennessee 2008 2008


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