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Region 10 Summary of State Information

Map of the Region 10 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 10

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)
   Good Waters 41,519 158,576 25 1 176
   Threatened Waters 48
   Impaired Waters 67,301 675,594 1 22 200
Total Assessed Waters 108,869 834,171 26 23 376
Total Waters 665,857 14,124,611 36,319 36,000 Unavailable
Percent of Waters Assessed 16.4 5.9 .1 .1 Unavailable

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Summary of Water Quality Assessments for Each Waterbody Type


Region 10
Water Quality Attainment in Assessed Rivers and Streams

Description of this table
Assessed Status Miles
Assessed 108,869
Unassessed 556,988
Total Miles 665,857







arrow pointing right 		Description of this table
Attainment Status Miles
Good 41,519
Threatened 48
Impaired 67,301
Total Miles Assessed 108,869

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Region 10
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 44,464 32.5 .0 67.5 color.gifcolor.gif
Recreation Recreation 7,251 59.8 .0 40.2 color.gifcolor.gif
Aesthetic Value Aesthetic Value 3,654 69.5 .0 30.5 color.gifcolor.gif
Aquatic Life Harvesting Aquatic Life Harvesting 1,973 37.2 .0 62.8 color.gifcolor.gif
Public Water Supply Public Water Supply 683 23.3 .0 76.7 color.gifcolor.gif
Agricultural Agricultural 1 .0 .0 100.0 color.gif

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Region 10
Causes of Impairment in Assessed Rivers and Streams

Description of this table
Cause of Impairment Group Miles
Threatened or
Impaired
Temperature color.gif 33,329
Sediment color.gif 29,127
Nutrients color.gif 23,033
Pathogens color.gif 10,159
pH/Acidity/Caustic Conditions color.gif 6,280
Organic Enrichment/Oxygen Depletion color.gif 6,144
Flow Alteration(s) color.gif 5,413
Cause Unknown - Impaired Biota color.gif 5,266
Habitat Alterations color.gif 4,330
Metals (other than Mercury) color.gif 3,204
Cause Unknown color.gif 2,478
Turbidity color.gif 2,439
Ammonia color.gif 1,514
Mercury color.gif 1,194
Algal Growth color.gif 1,004
Toxic Organics color.gif 975
Pesticides color.gif 864
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 753
Oil and Grease color.gif 731
Dioxins color.gif 681
Toxic Inorganics color.gif 509
Other Cause color.gif 509
Polychlorinated Biphenyls (PCBs) color.gif 367
Radiation color.gif 242
Chlorine color.gif 60
Noxious Aquatic Plants color.gif 27
Total Toxics color.gif 23
Cause Unknown - Fish Kills color.gif 10
Nuisance Exotic Species color.gif 10
Trash color.gif 8

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Region 10
Probable Sources of Impairments in Assessed Rivers and Streams

Description of this table
Probable Source Group Miles
Threatened or
Impaired
Agriculture color.gif 3,591
Hydromodification color.gif 1,199
Habitat Alterations (Not Directly Related To Hydromodification) color.gif 637
Resource Extraction color.gif 607
Unknown color.gif 590
Silviculture (Forestry) color.gif 480
Urban-Related Runoff/Stormwater color.gif 436
Natural/Wildlife color.gif 334
Municipal Dishcarges/Sewage color.gif 150
Construction color.gif 143
Industrial color.gif 44
Other color.gif 38
Recreation And Tourism (Non-Boating) color.gif 38
Spills/Dumping color.gif 22
Aquaculture color.gif 9
Land Application/Waste Sites/Tanks color.gif 5
Military Bases color.gif 5
Legacy/Historical Pollutants color.gif 5

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Region 10
Water Quality Attainment in Assessed Lakes, Reservoirs, and Ponds

Description of this table
Assessed Status Acres
Assessed 834,171
Unassessed 13,290,440
Total Acres 14,124,611







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Attainment Status Acres
Good 158,576
Threatened 0
Impaired 675,594
Total Acres Assessed 834,171

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Region 10
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 132,430 4.2 .0 95.8 color.gifcolor.gif
Aesthetic Value Aesthetic Value 92,907 1.7 .0 98.3 color.gifcolor.gif
Recreation Recreation 9,357 15.9 .0 84.1 color.gifcolor.gif
Aquatic Life Harvesting Aquatic Life Harvesting 3,649 94.2 .0 5.8 color.gifcolor.gif

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Region 10
Causes of Impairment in Assessed Lakes, Reservoirs, and Ponds

Description of this table
Cause of Impairment Group Acres
Threatened or
Impaired
Nutrients color.gif 202,977
Organic Enrichment/Oxygen Depletion color.gif 155,691
Sediment color.gif 149,152
Algal Growth color.gif 147,656
Mercury color.gif 142,504
Temperature color.gif 131,973
Flow Alteration(s) color.gif 84,794
Habitat Alterations color.gif 84,704
pH/Acidity/Caustic Conditions color.gif 84,069
Polychlorinated Biphenyls (PCBs) color.gif 76,036
Dioxins color.gif 71,696
Nuisance Exotic Species color.gif 67,118
Pesticides color.gif 55,541
Other Cause color.gif 49,500
Pathogens color.gif 44,528
Metals (other than Mercury) color.gif 31,010
Turbidity color.gif 9,798
Cause Unknown color.gif 6,436
Total Toxics color.gif 6,320
Oil and Grease color.gif 3,100
Ammonia color.gif 372
Cause Unknown - Impaired Biota color.gif 142
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 130

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Region 10
Probable Sources of Impairments in Assessed Lakes, Reservoirs, and Ponds

Description of this table
Probable Source Group Acres
Threatened or
Impaired
Recreation And Tourism (Non-Boating) color.gif 3,100
Municipal Dishcarges/Sewage color.gif 1,137
Urban-Related Runoff/Stormwater color.gif 417
Agriculture color.gif 22
Silviculture (Forestry) color.gif 13
Hydromodification color.gif 13
Habitat Alterations (Not Directly Related To Hydromodification) color.gif 5
Military Bases color.gif 2
Land Application/Waste Sites/Tanks color.gif 2
Spills/Dumping color.gif 0

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Region 10
Water Quality Attainment in Assessed Bays and Estuaries

Description of this table
Assessed Status Square Miles
Assessed 26
Unassessed 36,293
Total Square Miles 36,319







arrow pointing right 		Description of this table
Attainment Status Square Miles
Good 25
Threatened 0
Impaired 1
Total Square Miles Assessed 26

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Region 10
Designated Use Support in Assessed Bays and Estuaries*

No designated uses reported.

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Region 10
Causes of Impairment in Assessed Bays and Estuaries

Description of this table
Cause of Impairment Group Square Miles
Threatened or
Impaired
Trash color.gif 0
Toxic Inorganics color.gif 0
Organic Enrichment/Oxygen Depletion color.gif 0
Other Cause color.gif 0
Toxic Organics color.gif 0
Ammonia color.gif 0
Metals (other than Mercury) color.gif 0
Mercury color.gif 0
Oil and Grease color.gif 0

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Region 10
Probable Sources of Impairments in Assessed Bays and Estuaries

Description of this table
Probable Source Group Square Miles
Threatened or
Impaired
Industrial color.gif 0
Aquaculture color.gif 0
Urban-Related Runoff/Stormwater color.gif 0
Silviculture (Forestry) color.gif 0
Legacy/Historical Pollutants color.gif 0
Resource Extraction color.gif 0

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Region 10
Water Quality Attainment in Assessed Coastal Shoreline

Description of this table
Assessed Status Miles
Assessed 23
Unassessed 35,977
Total Miles 36,000







arrow pointing right 		Description of this table
Attainment Status Miles
Good 1
Threatened 0
Impaired 22
Total Miles Assessed 23

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Region 10
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
Aquatic Life Harvesting Aquatic Life Harvesting 5 20.0 .0 80.0 color.gifcolor.gif

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Region 10
Causes of Impairment in Assessed Coastal Shoreline

Description of this table
Cause of Impairment Group Miles
Threatened or
Impaired
Oil and Grease color.gif 13
Other Cause color.gif 5
Pathogens color.gif 4

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Region 10
Probable Sources of Impairments in Assessed Coastal Shoreline

Description of this table
Probable Source Group Miles
Threatened or
Impaired
Spills/Dumping color.gif 13
Industrial color.gif 5

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Region 10
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 376
Unassessed Unavailable
Total Square Miles Unavailable







arrow pointing right 		Description of this table
Attainment Status Square Miles
Good 176
Threatened 0
Impaired 200
Total Square Miles Assessed 376

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Region 10
Designated Use Support in Assessed Ocean and Near Coastal*

No designated uses reported.

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Region 10
Causes of Impairment in Assessed Ocean and Near Coastal

Description of this table
Cause of Impairment Group Square Miles
Threatened or
Impaired
Pathogens color.gif 63
Organic Enrichment/Oxygen Depletion color.gif 45
Nuisance Exotic Species color.gif 35
Total Toxics color.gif 26
Polychlorinated Biphenyls (PCBs) color.gif 16
Metals (other than Mercury) color.gif 15
Toxic Organics color.gif 14
Mercury color.gif 12
Pesticides color.gif 10
Habitat Alterations color.gif 10
Dioxins color.gif 9
Ammonia color.gif 1

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Region 10
Probable Sources of Impairments in Assessed Ocean and Near Coastal

No probable sources of impairments reported.

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Region 10 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)
Algal Growth 1,004 147,656      
Ammonia 1,514 372 0   1
Cause Unknown 2,478 6,436      
Cause Unknown - Fish Kills 10        
Cause Unknown - Impaired Biota 5,266 142      
Chlorine 60        
Dioxins 681 71,696     9
Flow Alteration(s) 5,413 84,794      
Habitat Alterations 4,330 84,704     10
Mercury 1,194 142,504 0   12
Metals (other than Mercury) 3,204 31,010 0   15
Noxious Aquatic Plants 27        
Nuisance Exotic Species 10 67,118     35
Nutrients 23,033 202,977      
Oil and Grease 731 3,100 0 13  
Organic Enrichment/Oxygen Depletion 6,144 155,691 0   45
Other Cause 509 49,500 0 5  
Pathogens 10,159 44,528   4 63
Pesticides 864 55,541     10
pH/Acidity/Caustic Conditions 6,280 84,069      
Polychlorinated Biphenyls (PCBs) 367 76,036     16
Radiation 242        
Salinity/Total Dissolved Solids/Chlorides/Sulfates 753 130      
Sediment 29,127 149,152      
Temperature 33,329 131,973      
Total Toxics 23 6,320     26
Toxic Inorganics 509   0    
Toxic Organics 975   0   14
Trash 8   0    
Turbidity 2,439 9,798      

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Region 10 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)
Agriculture 3,591 22    
Aquaculture 9   0  
Construction 143      
Habitat Alterations (Not Directly Related To Hydromodification) 637 5    
Hydromodification 1,199 13    
Industrial 44   0 5
Land Application/Waste Sites/Tanks 5 2    
Legacy/Historical Pollutants 5   0  
Military Bases 5 2    
Municipal Dishcarges/Sewage 150 1,137    
Natural/Wildlife 334      
Other 38      
Recreation And Tourism (Non-Boating) 38 3,100    
Resource Extraction 607   0  
Silviculture (Forestry) 480 13 0  
Spills/Dumping 22 0   13
Unknown 590      
Urban-Related Runoff/Stormwater 436 417 0  

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Region 10 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
2006 color.gif 2 2

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Region 10
Impaired Waters Listed By State

Description of this table
State Name Number of Waters on 303(d) List
Alaska color.gif 32
Idaho color.gif 1,056
Oregon color.gif 1,397
Washington color.gif 2,419

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Region 10 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
Temperature color.gif 1,416 1,417
Pathogens color.gif 737 737
Sediment color.gif 457 465
Nutrients color.gif 390 401
Metals (other than Mercury) color.gif 209 209
Organic Enrichment/Oxygen Depletion color.gif 165 165
Turbidity color.gif 161 161
Pesticides color.gif 74 83
Other Cause color.gif 71 71
Ammonia color.gif 50 50
pH/Acidity/Caustic Conditions color.gif 28 28
Algal Growth color.gif 17 17
Mercury color.gif 16 16
Polychlorinated Biphenyls (PCBs) color.gif 9 9
Chlorine color.gif 2 2
Nuisance Exotic Species color.gif 2 2
Total Toxics color.gif 2 2
Toxic Organics color.gif 2 2
Dioxins color.gif 1 1
Oil and Grease color.gif 1 1

Total: 3,810 TMDLs; 3,839 Causes of Impairment Addressed

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Region 10 Approved TMDLs By State

This chart includes TMDLs since October 1, 1995.

Description of this table
State Name Number of TMDLs
Alaska color.gif 57
Idaho color.gif 1,616
Oregon color.gif 1,080
Washington color.gif 1,207

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Region 10 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 61 61
1997 color.gif 68 68
1998 color.gif 5 5
1999 color.gif 56 58
2000 color.gif 548 548
2001 color.gif 286 290
2002 color.gif 235 235
2003 color.gif 279 279
2004 color.gif 357 359
2005 color.gif 381 381
2006 color.gif 421 432
2007 color.gif 489 495
2008 color.gif 313 313
2009 color.gif 310 313
2010 color.gif 1 2

Total: 3,810 TMDLs; 3,839 Causes of Impairment Addressed

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Region 10 Cumulative Number of TMDLs for Indian Country Waters

EPA Fiscal Year starts October 1 and ends September 30.


Description of this table
NOTE:Click on the underlined "Number of TMDLs" value for a detailed list of the TMDLs for the fiscal year.
Fiscal Year Number of TMDLs Number of Causes of
Impairment Addressed
1999 color.gif 9 9
2000 color.gif 124 124
2004 color.gif 17 17
2005 color.gif 10 10

Total: 160 TMDLs; 160 Causes of Impairment



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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
Alaska 2008 2008
Idaho 2008 2008
Oregon 2006 2006
Washington 2008 2008


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