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Rhode Island Assessment Summary for Reporting Year 2008

Description of this table

	Size of Water
	Rivers and Streams (Miles)	Lakes, Reservoirs, and Ponds (Acres)	Bays and Estuaries (Square Miles)	Coastal Shoreline (Miles)
Good Waters	405.6	7,603.7	102.1	78.6
Previously impaired waters       now attaining all uses		29.4	.0
Threatened Waters
TMDL completed
TMDL alternative
Non-pollutant impairment
TMDL needed
Impaired Waters	334.1	8,741.3	56.3
TMDL completed	49.9	3,243.0	2.5
TMDL alternative
Non-pollutant impairment	23.5	3,890.0	.9
TMDL needed	260.8	1,608.2	52.9
New TMDLs completed	5.7	.0	.0	.0
Remaining TMDLs needed	255.1	1,608.2	52.9
Total Assessed Waters	739.8	16,345.0	158.4	78.6
Total Waters	1,498.0	20,749.0	158.5	79.0
Percent of Waters Assessed	49.4	78.8	99.9	99.5

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Summary of Water Quality Assessments for Each Waterbody Type
for Reporting Year 2008

Rhode Island Assessed Waters
Summary of Water Quality Attainment for Rivers and Streams
Reporting Year 2008

Description of this table Assessed Status Miles Assessed 739.8 Unassessed 758.2 Total Miles 1,498.0

Description of this table Attainment Status Miles Good 405.6 Threatened .0 Impaired 334.1 Total Miles Assessed 739.8

Description of this table TMDL Development Status Miles All TMDLs completed 55.6 TMDL alternative .0 Non-pollutant impairment 23.5 TMDL needed 255.1 Total Threatened and Impaired 334.1

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Rhode Island Assessed Waters
Designated Use Support for Rivers and Streams
Reporting Year 2008*

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

Description of this table

Designated Use	Miles Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
					% Threatened
					% Impaired
Fish And Wildlife Habitat	649.9	69.5	.0	30.5
Fish Consumption	49.5	20.1	.0	79.9
Primary Contact Recreation	606.0	60.4	.0	39.6
Public Drinking Water Supply	6.1	100.0	.0	.0
Secondary Contact Recreation	606.0	60.4	.0	39.6
Shellfish Controlled Relay And Depuration	.2	.0	.0	100.0

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Rhode Island Causes of Impairment
for Threatened and Impaired Rivers and Streams
Reporting Year 2008

Description of this table

Cause of Impairment	Cause of Impairment Group	Miles Threatened or Impaired
Fecal Coliform	Pathogens	197.0
Benthic Macroinvertebrates Bioassessments	Cause Unknown - Impaired Biota	103.2
Lead	Metals (other than Mercury)	82.7
Copper	Metals (other than Mercury)	63.3
Cadmium	Metals (other than Mercury)	42.3
Non-Native Aquatic Plants	Nuisance Exotic Species	40.1
Enterococcus Bacteria	Pathogens	40.0
Mercury in Fish Tissue	Mercury	39.6
Dissolved Oxygen	Organic Enrichment/Oxygen Depletion	33.0
Phosphorus, Total	Nutrients	28.5
PCB(s) in Fish Tissue	Polychlorinated Biphenyls (PCBs)	24.3
Zinc	Metals (other than Mercury)	19.9
Iron	Metals (other than Mercury)	15.2
Aquatic Macroinvertebrate Bioassessments	Cause Unknown - Impaired Biota	12.6
Escherichia Coli (E. Coli)	Pathogens	10.7
Polychlorinated Biphenyls (PCBs)	Polychlorinated Biphenyls (PCBs)	8.4
Dioxin (Including 2,3,7,8-TCDD)	Dioxins	8.4
Mercury	Mercury	8.4
Ambient Bioassays - Chronic Aquatic Toxicity	Total Toxics	7.9
Mercury in Water Column	Mercury	4.6
Whole Effluent Toxicity (WET)	Total Toxics	2.2
Eurasian Water Milfoil, Myriophyllum Spicatum	Nuisance Exotic Species	1.6
Aquatic Plants - Native	Nuisance Native Species	1.6

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Rhode Island Probable Sources of Impairments
for Threatened and Impaired Rivers and Streams
Reporting Year 2008

Description of this table

Probable Source	Probable Source Group	Miles Threatened or Impaired
Source Unknown	Unknown	208.9
Urban Runoff/Storm Sewers	Urban-Related Runoff/Stormwater	77.6
Wildlife Other Than Waterfowl	Natural/Wildlife	45.0
Introduction Of Non-Native Organisms (Accidental Or Intentional)	Other	40.1
Municipal Point Source Discharges	Municipal Dishcarges/Sewage	32.8
On-Site Treatment Systems (Septic Systems And Similar Decentralized Systems)	Municipal Dishcarges/Sewage	24.2
Cercla Npl (Superfund) Sites	Legacy/Historical Pollutants	22.6
Waterfowl	Natural/Wildlife	21.7
Agriculture	Agriculture	18.3
Impervious Surface/Parking Lot Runoff	Urban-Related Runoff/Stormwater	17.6
Contaminated Groundwater	Groundwater Loadings/Withdrawals	16.8
Highway/Road/Bridge Runoff (Non-Construction Related)	Urban-Related Runoff/Stormwater	13.3
Landfills	Land Application/Waste Sites/Tanks	12.9
Upstream/Downstream Source	Other	11.7
Combined Sewer Overflows	Municipal Dishcarges/Sewage	11.4
Atmospheric Deposition - Toxics	Atmospheric Deposition	11.0
Illicit Connections/Hook-Ups To Storm Sewers	Municipal Dishcarges/Sewage	9.3
Contaminated Sediments	Legacy/Historical Pollutants	8.4
Natural Sources	Natural/Wildlife	5.2
Sanitary Sewer Overflows (Collection System Failures)	Municipal Dishcarges/Sewage	4.9
Golf Courses	Recreation And Tourism (Non-Boating)	4.5
Manure Runoff	Agriculture	4.4
Impacts From Hydrostructure Flow Regulation/Modification	Hydromodification	3.2
Animal Feeding Operations (Nps)	Agriculture	2.7
Industrial Point Source Discharge	Industrial	2.2
Unrestricted Cattle Access	Agriculture	1.6
Internal Nutrient Recycling	Natural/Wildlife	1.6
Wastes From Pets	Urban-Related Runoff/Stormwater	1.1
Illegal Dumps Or Other Inappropriate Waste Disposal	Spills/Dumping	.7

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Rhode Island Assessed Waters
Summary of Water Quality Attainment for Lakes, Reservoirs, and Ponds
Reporting Year 2008

Description of this table Assessed Status Acres Assessed 16,345.0 Unassessed 4,404.0 Total Acres 20,749.0

Description of this table Attainment Status Acres Good 7,603.7 Threatened .0 Impaired 8,741.3 Total Acres Assessed 16,345.0

Description of this table TMDL Development Status Acres All TMDLs completed 3,243.0 TMDL alternative .0 Non-pollutant impairment 3,890.0 TMDL needed 1,608.2 Total Threatened and Impaired 8,741.3

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Rhode Island Assessed Waters
Designated Use Support for Lakes, Reservoirs, and Ponds
Reporting Year 2008*

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

Description of this table

Designated Use	Acres Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
					% Threatened
					% Impaired
Fish And Wildlife Habitat	14,940.6	51.7	.0	48.3
Fish Consumption	3,123.8	23.4	.0	76.6
Primary Contact Recreation	14,487.9	96.1	.0	3.9
Public Drinking Water Supply	5,484.0	99.0	.0	1.0
Secondary Contact Recreation	14,487.9	96.1	.0	3.9

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Rhode Island Causes of Impairment
for Threatened and Impaired Lakes, Reservoirs, and Ponds
Reporting Year 2008

Description of this table

Cause of Impairment	Cause of Impairment Group	Acres Threatened or Impaired
Non-Native Aquatic Plants	Nuisance Exotic Species	3,889.1
Mercury in Fish Tissue	Mercury	2,315.0
Phosphorus, Total	Nutrients	2,205.2
Dissolved Oxygen	Organic Enrichment/Oxygen Depletion	1,492.6
Non-Native Fish/Shellfish/Zooplankton	Nuisance Exotic Species	1,332.1
Excess Algal Growth	Algal Growth	1,079.5
Lead	Metals (other than Mercury)	725.2
Fecal Coliform	Pathogens	561.6
Other Flow Regime Alterations	Flow Alteration(s)	497.1
Copper	Metals (other than Mercury)	488.2
Eurasian Water Milfoil, Myriophyllum Spicatum	Nuisance Exotic Species	301.8
Turbidity	Turbidity	163.9
PCB(s) in Fish Tissue	Polychlorinated Biphenyls (PCBs)	76.7
Taste and Odor	Taste, Color and Odor	42.2
Benthic Macroinvertebrates Bioassessments	Cause Unknown - Impaired Biota	40.7
Aquatic Macroinvertebrate Bioassessments	Cause Unknown - Impaired Biota	38.0
Total Suspended Solids (TSS)	Turbidity	26.3
Chloride	Salinity/Total Dissolved Solids/Chlorides/Sulfates	26.3
Chlorophyll-A	Algal Growth	12.7

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Rhode Island Probable Sources of Impairments
for Threatened and Impaired Lakes, Reservoirs, and Ponds
Reporting Year 2008

Description of this table

Probable Source	Probable Source Group	Acres Threatened or Impaired
Introduction Of Non-Native Organisms (Accidental Or Intentional)	Other	4,591.2
Atmospheric Deposition - Toxics	Atmospheric Deposition	2,315.0
Source Unknown	Unknown	2,012.4
Urban Runoff/Storm Sewers	Urban-Related Runoff/Stormwater	1,501.9
Internal Nutrient Recycling	Natural/Wildlife	1,155.3
Waterfowl	Natural/Wildlife	837.9
Agriculture	Agriculture	522.4
Upstream/Downstream Source	Other	361.5
Flow Alterations From Water Diversions	Hydromodification	316.0
Impacts From Hydrostructure Flow Regulation/Modification	Hydromodification	316.0
Post-Development Erosion And Sedimentation	Hydromodification	311.2
Wildlife Other Than Waterfowl	Natural/Wildlife	262.3
On-Site Treatment Systems (Septic Systems And Similar Decentralized Systems)	Municipal Dishcarges/Sewage	221.4
Illegal Dumps Or Other Inappropriate Waste Disposal	Spills/Dumping	143.4
Wastes From Pets	Urban-Related Runoff/Stormwater	119.0
Sanitary Sewer Overflows (Collection System Failures)	Municipal Dishcarges/Sewage	113.2
Atmospheric Deposition - Nitrogen	Atmospheric Deposition	104.9
Municipal Point Source Discharges	Municipal Dishcarges/Sewage	38.0
Combined Sewer Overflows	Municipal Dishcarges/Sewage	38.0

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Rhode Island Assessed Waters
Summary of Water Quality Attainment for Bays and Estuaries
Reporting Year 2008

Description of this table Assessed Status Square Miles Assessed 158.4 Unassessed .1 Total Square Miles 158.5

Description of this table Attainment Status Square Miles Good 102.1 Threatened .0 Impaired 56.3 Total Square Miles Assessed 158.4

Description of this table TMDL Development Status Square Miles All TMDLs completed 2.5 TMDL alternative .0 Non-pollutant impairment .9 TMDL needed 52.9 Total Threatened and Impaired 56.3

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Rhode Island Assessed Waters
Designated Use Support for Bays and Estuaries
Reporting Year 2008*

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

Description of this table

Designated Use	Square Miles Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
					% Threatened
					% Impaired
Fish And Wildlife Habitat	111.7	54.8	.0	45.2
Fish Consumption	158.1	100.0	.0	.0
Primary Contact Recreation	154.7	89.9	.0	10.1
Secondary Contact Recreation	154.7	89.9	.0	10.1
Shellfish Consumption	131.3	79.3	.0	20.7
Shellfish Controlled Relay And Depuration	16.5	95.4	.0	4.6

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Rhode Island Causes of Impairment
for Threatened and Impaired Bays and Estuaries
Reporting Year 2008

Description of this table

Cause of Impairment	Cause of Impairment Group	Square Miles Threatened or Impaired
Dissolved Oxygen	Organic Enrichment/Oxygen Depletion	48.6
Fecal Coliform	Pathogens	41.9
Nitrogen, Total	Nutrients	39.5
Temperature, Water	Temperature	9.8
Fish Bioassessments	Cause Unknown - Impaired Biota	9.8
Sediment Bioassays for Estuarine and Marine Water	Total Toxics	1.0
Non-Native Aquatic Plants	Nuisance Exotic Species	.9

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Rhode Island Probable Sources of Impairments
for Threatened and Impaired Bays and Estuaries
Reporting Year 2008

Description of this table

Probable Source	Probable Source Group	Square Miles Threatened or Impaired
Source Unknown	Unknown	38.4
Combined Sewer Overflows	Municipal Dishcarges/Sewage	27.8
Industrial Thermal Discharges	Industrial	9.8
Cooling Water Intake Structures (Impingement Or Entrainment)	Industrial	9.8
On-Site Treatment Systems (Septic Systems And Similar Decentralized Systems)	Municipal Dishcarges/Sewage	7.2
Urban Runoff/Storm Sewers	Urban-Related Runoff/Stormwater	5.7
Wildlife Other Than Waterfowl	Natural/Wildlife	2.8
Waterfowl	Natural/Wildlife	2.8
Upstream/Downstream Source	Other	1.7
Contaminated Sediments	Legacy/Historical Pollutants	1.0
Municipal Point Source Discharges	Municipal Dishcarges/Sewage	1.0
Rcra Hazardous Waste Sites	Industrial	1.0
Highway/Road/Bridge Runoff (Non-Construction Related)	Urban-Related Runoff/Stormwater	.9
Impervious Surface/Parking Lot Runoff	Urban-Related Runoff/Stormwater	.9
Introduction Of Non-Native Organisms (Accidental Or Intentional)	Other	.9
Agriculture	Agriculture	.7
Wastes From Pets	Urban-Related Runoff/Stormwater	.5
Landfills	Land Application/Waste Sites/Tanks	.1

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Rhode Island Assessed Waters
Summary of Water Quality Attainment for Coastal Shoreline
Reporting Year 2008

Description of this table Assessed Status Miles Assessed 78.6 Unassessed .4 Total Miles 79.0

Description of this table Attainment Status Miles Good 78.6 Threatened .0 Impaired .0 Total Miles Assessed 78.6

Description of this table TMDL Development Status Miles All TMDLs completed .0 TMDL alternative .0 Non-pollutant impairment .0 TMDL needed .0 Total Threatened and Impaired .0

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Rhode Island Assessed Waters
Designated Use Support for Coastal Shoreline
Reporting Year 2008*

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

Description of this table

Designated Use	Miles Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
					% Threatened
					% Impaired
Fish Consumption	78.6	100.0	.0	.0
Primary Contact Recreation	78.6	100.0	.0	.0
Secondary Contact Recreation	78.6	100.0	.0	.0
Shellfish Consumption	78.6	100.0	.0	.0

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Rhode Island Causes of Impairment
for Threatened and Impaired Coastal Shoreline
Reporting Year 2008

No causes of impairment reported.

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Rhode Island Probable Sources of Impairments
for Threatened and Impaired Coastal Shoreline
Reporting Year 2008

No probable sources of impairments reported.

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Rhode Island Causes of Impairment for Reporting Year 2008

Description of this table

NOTE: Click on the underlined Cause of Impairment Group to see a list of specific state causes of impairment making up the Cause of Impairment Group.
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)
Algal Growth		1,079.5
Cause Unknown - Impaired Biota	111.8	78.7	9.8
Dioxins	8.4
Flow Alteration(s)		497.1
Mercury	44.2	2,315.0
Metals (other than Mercury)	139.6	725.2
Nuisance Exotic Species	40.1	4,940.3	.9
Nuisance Native Species	1.6
Nutrients	28.5	2,205.2	39.5
Organic Enrichment/Oxygen Depletion	33.0	1,492.6	48.6
Pathogens	240.2	561.6	41.9
Polychlorinated Biphenyls (PCBs)	24.3	76.7
Salinity/Total Dissolved Solids/Chlorides/Sulfates		26.3
Taste, Color and Odor		42.2
Temperature			9.8
Total Toxics	10.0		1.0
Turbidity		190.2

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Rhode Island Probable Sources Contributing to Impairments
for Reporting Year 2008

Description of this table

NOTE: Click on the underlined Probable Source Group to see a list of specific state Probable Sources making up the Probable Source Group.
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	22.7	522.4	.7
Atmospheric Deposition	11.0	2,419.9
Groundwater Loadings/Withdrawals	16.8
Hydromodification	3.2	514.0
Industrial	2.2		10.8
Land Application/Waste Sites/Tanks	12.9		.1
Legacy/Historical Pollutants	22.6		1.0
Municipal Dishcarges/Sewage	64.3	372.6	35.0
Natural/Wildlife	55.0	1,359.0	2.8
Other	51.8	4,924.5	2.6
Recreation And Tourism (Non-Boating)	4.5
Spills/Dumping	.7	143.4
Unknown	208.9	2,012.4	38.4
Urban-Related Runoff/Stormwater	79.6	1,501.9	6.6

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Rhode Island TMDL Alternatives by Cause of Impairment 2008

Description of this table

NOTE: Click on the underlined "Number of TMDL Alternatives by Cause of Impairment " value to see a listing of those Causes of Impairment.
Cause of Impairment	Number of TMDL Alternatives	Bays and Estuaries (Square Miles)
Fish Bioassessments	4	10
Temperature, Water	4	10

Total: 8 TMDL Alternatives

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Rhode Island 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
2008	4	4

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Rhode Island 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	73
Metals (other than Mercury)	67
Nutrients	43
Organic Enrichment/Oxygen Depletion	38
Cause Unknown - Impaired Biota	32
Mercury	10
Polychlorinated Biphenyls (PCBs)	7
Total Toxics	7
Turbidity	3
Algal Growth	2
Dioxins	2
Salinity/Total Dissolved Solids/Chlorides/Sulfates	1

Total: 285 Causes of Impairment

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Rhode Island Cumulative TMDLs by Pollutant

This chart includes TMDLs since October 1, 1995.

Description of this table

NOTE: Click on the underlined "Pollutant" value to see associated listed waters for which a TMDL was developed. Click on the underlined "Number of TMDLs" value to see a listing of those TMDLs for the pollutant.
Pollutant	Number of TMDLs	Number of Causes of Impairment Addressed
Fecal Coliform	35	35
Pathogens	20	20
Mercury	19	19
Phosphorus, Total	15	35
Enterococcus Bacteria	6	6
Zinc	4	4
Copper	2	2
Lead	2	2
Nutrients	1	4

Total: 104 TMDLs; 127 Causes of Impairment Addressed

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Rhode Island 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
1999	1	3
2001	3	3
2002	7	7
2003	5	5
2004	3	6
2005	2	2
2006	25	28
2007	18	30
2008	28	31
2009	12	12

Total: 104 TMDLs; 127 Causes of Impairment Addressed

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