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Assessment Data for the State of Connecticut Year 2002

National Assessment Database
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Assessing Water Quality (Questions and Answers)

National Water Quality Inventory Report to Congress, 2002 Reporting Cycle

The 2002 National Assessment
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Previous National Water Quality Reports

EnviroMapper for Water

Impaired Water Information
2002 303(d) List Report

Other Water Assessment Information
The most current report available for this state is 2008.
Data are also available for these years: 2004 2006


State of Connecticut websites:

State 305(b) Water Quality Assessment Report(s)
  State Water Quality Program

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Total Assessed Waters for the State of Connecticut

 Description of this table

Size Of Water
Rivers, Streams, Creeks (Miles) Lakes, Ponds, Reservoir (Acres) Bays, Estuaries (Square Miles) Coastal Shorelines (Miles) Oceans, Near Coastal Waters (Square Miles) Wetlands (Acres) Great Lakes Shoreline (Miles) Great Lakes Open Water (Square Miles)
Total Assessed Waters 1,666.13 27,839.85 613.34 .00 .00 .00 .00 .00
Estimated Total Water Size in CT 5,830.00 64,973.00 613.34 Unavailable Unavailable Unavailable Unavailable Unavailable
Percent of Waters Assessed 28.58 42.85 100.00 Unavailable Unavailable Unavailable Unavailable Unavailable

Assessed Waters of Connecticut by Watershed

 Description of this table
Watershed Size of Water
Rivers, Streams, Creeks (Miles) Lakes, Ponds, Reservoir (Acres) Bays, Estuaries (Square Miles) Coastal Shorelines (Miles) Oceans, Near Coastal Waters (Square Miles) Wetlands (Acres) Great Lakes Shoreline (Miles) Great Lakes Open Water (Square Miles)
FARMINGTON 150.53 2,176.90 .00 .00 .00 .00 .00 .00
HOUSATONIC 380.10 14,058.20 5.84 .00 .00 .00 .00 .00
LOWER CONNECTICUT 325.60 3,657.50 12.34 .00 .00 .00 .00 .00
LOWER HUDSON 7.74 95.00 .00 .00 .00 .00 .00 .00
PAWCATUCK-WOOD 32.50 102.80 .42 .00 .00 .00 .00 .00
QUINEBAUG 141.10 3,631.85 .00 .00 .00 .00 .00 .00
QUINNIPIAC 190.00 612.60 310.12 .00 .00 .00 .00 .00
SAUGATUCK 145.35 194.60 191.90 .00 .00 .00 .00 .00
SHETUCKET 206.15 1,892.80 .00 .00 .00 .00 .00 .00
THAMES 87.06 1,417.60 92.72 .00 .00 .00 .00 .00

Connecticut Assessed Waters
Individual Use Support for Rivers and Streams

 Description of this table
State Designated Use Total Miles Assessed Percent Good Percent Threatened Percent Impaired color.gif% Good
color.gif% Threatened
color.gif% Impaired
Fish, Shellfish, and Wildlife Protection and Propagation Fish, Shellfish, and Wildlife Protection and Propagation 1,460.98 64.01 12.82 23.17 color.gifcolor.gifcolor.gif
Recreation Recreation 1,197.25 51.72 13.81 34.47 color.gifcolor.gifcolor.gif
Public Water Supply Public Water Supply 172.75 77.51 21.79 .69 color.gifcolor.gifcolor.gif
Aquatic Life Harvesting Aquatic Life Harvesting 1,665.40 92.27 .08 7.66 color.gifcolor.gifcolor.gif
Aesthetic Value Aesthetic Value 50.10 34.53 5.79 59.68 color.gifcolor.gifcolor.gif
Hydropower Generation Other 1.50 100.00 .00 .00 color.gif
The state assessed 1,666.13 miles of rivers and streams, or 28.58% of 5,830.00 total miles.

Connecticut Assessed Waters
Water Quality Attainment for Rivers and Streams

 Description of this table
Attainment Status Miles Percent of Assessed
Good 836.85 50.23
Threatened 218.95 13.14
Impaired 610.33 36.63
Total Miles Assessed 1,666.13 100.00

Connecticut Top Causes of Impairments
for Rivers and Streams

 Description of this table
# State Cause Name Total
Miles
Impaired
1 PATHOGENS 404.40
2 INDICATOR BACTERIA 382.70
3 CAUSE UNKNOWN 278.65
4 POLYCHLORINATED BIPHENYLS 125.50
5 SEDIMENTATION/SILTATION 100.10
6 ORGANIC ENRICHMENT/LOW DO 90.50
7 FLOW ALTERATION 62.90
8 NUTRIENTS 61.80
9 OTHER HABITAT ALTERATIONS 39.80
10 TURBIDITY 27.50

Connecticut Top Probable Sources of Impairments
for Rivers and Streams

 Description of this table
# State Source Name Total Miles Impaired by Source
1 SOURCE UNKNOWN 356.80
2 MUNICIPAL (URBANIZED HIGH DENSITY AREA) 244.65
3 MUNICIPAL POINT SOURCE DISCHARGES 122.00
4 INDUSTRIAL POINT SOURCE DISCHARGE 98.83
5 HYDROMODIFICATION 80.90
6 COMBINED SEWER OVERFLOWS 74.30
7 FLOW ALTERATIONS FROM WATER DIVERSIONS 73.10
8 SANITARY SEWER OVERFLOWS (COLLECTION SYSTEM FAILURES) 72.10
9 SOURCES OUTSIDE STATE JURISDICTION OR BORDERS 55.30
10 LANDFILLS 40.90

Connecticut Assessed Waters
Individual Use Support for Lakes, Ponds and Reservoirs

 Description of this table
State Designated Use Total Acres Assessed Percent Good Percent Threatened Percent Impaired color.gif% Good
color.gif% Threatened
color.gif% Impaired
Fish, Shellfish, and Wildlife Protection and Propagation Fish, Shellfish, and Wildlife Protection and Propagation 27,514.80 47.26 48.98 3.76 color.gifcolor.gifcolor.gif
Recreation Recreation 26,844.60 32.16 61.69 6.15 color.gifcolor.gifcolor.gif
Public Water Supply Public Water Supply 1,248.80 43.88 56.12 .00 color.gifcolor.gif
Aquatic Life Harvesting Aquatic Life Harvesting 27,838.45 85.15 .00 14.85 color.gifcolor.gif
Aesthetic Value Aesthetic Value 27,070.70 33.47 64.05 2.48 color.gifcolor.gifcolor.gif
The state assessed 27,839.85 acres of lakes, ponds and reservoirs, or 42.85% of 64,973.00 total acres.

Connecticut Assessed Waters
Water Quality Attainment for Lakes, Ponds and Reservoirs

 Description of this table
Attainment Status Acres Percent of Assessed
Good 4,708.60 16.91
Threatened 17,578.40 63.14
Impaired 5,552.85 19.95
Total Acres Assessed 27,839.85 100.00

Connecticut Top Causes of Impairments
for Lakes, Ponds and Reservoirs

 Description of this table
# State Cause Name Total
Acres
Impaired
1 POLYCHLORINATED BIPHENYLS 3,412.55
2 PRIORITY ORGANICS 2,227.00
3 ORGANIC ENRICHMENT/LOW DO 1,549.60
4 SUSPENDED ALGAE 1,282.50
5 MERCURY 1,143.75
6 NUTRIENTS 939.50
7 NON-NATIVE AQUATIC PLANTS 825.10
8 NON-NATIVE FISH/SHELLFISH/ZOOPLANKTON SPECIES 477.30
9 INDICATOR BACTERIA 376.50
10 PATHOGENS 376.50

Connecticut Top Probable Sources of Impairments
for Lakes, Ponds and Reservoirs

 Description of this table
# State Source Name Total Acres Impaired by Source
1 CONTAMINATED SEDIMENTS 3,443.55
2 INDUSTRIAL POINT SOURCE DISCHARGE 3,360.55
3 SOURCES OUTSIDE STATE JURISDICTION OR BORDERS 3,203.20
4 SOURCE UNKNOWN 1,232.40
5 HIGHWAYS, ROADS, BRIDGES, INFRASTRUCTURE (NEW CONSTRUCTION) 1,150.90
6 UPSTREAM IMPOUNDMENTS (E.G., PL-566 NRCS STRUCTURES) 975.00
7 HYDROMODIFICATION 975.00
8 ATMOSPHERIC DEPOSITON - TOXICS 630.40
9 MUNICIPAL (URBANIZED HIGH DENSITY AREA) 528.00
10 CHANGES IN ORDINARY STRATIFICATION AND BOTTOM WATER HYPOXIA/ANOXIA 488.00

Connecticut Assessed Waters
Individual Use Support for Bays and Estuaries

 Description of this table
State Designated Use Total Square Miles Assessed Percent Good Percent Threatened Percent Impaired color.gif% Good
color.gif% Threatened
color.gif% Impaired
Fish, Shellfish, and Wildlife Protection and Propagation Fish, Shellfish, and Wildlife Protection and Propagation 613.34 61.25 .05 38.70 color.gifcolor.gifcolor.gif
Recreation Recreation 608.88 87.34 7.81 4.85 color.gifcolor.gifcolor.gif
Aquatic Life Harvesting Aquatic Life Harvesting 613.34 68.86 .00 31.14 color.gifcolor.gif
The state assessed 613.34 square miles of bays and estuaries, or 100.00% of 613.34 total square miles.

Connecticut Assessed Waters
Water Quality Attainment for Bays and Estuaries

 Description of this table
Attainment Status Square Miles Percent of Assessed
Good 197.89 32.26
Threatened 18.84 3.07
Impaired 396.61 64.66
Total Square Miles Assessed 613.34 100.00

Connecticut Top Causes of Impairments
for Bays and Estuaries

 Description of this table
# State Cause Name Total
Square Miles
Impaired
1 NUTRIENTS 232.14
2 ORGANIC ENRICHMENT/LOW DO 225.20
3 PATHOGENS 191.22
4 INDICATOR BACTERIA 182.68
5 NITROGEN, AMMONIA (TOTAL AMMONIA) 16.60
6 PRIORITY ORGANICS 13.39
7 UNKNOWN TOXICITY 12.34
8 OIL AND GREASE 11.35
9 POLYCHLORINATED BIPHENYLS 9.38
10 NONPRIORITY ORGANICS 5.76

Connecticut Top Probable Sources of Impairments
for Bays and Estuaries

 Description of this table
# State Source Name Total Square Miles Impaired by Source
1 MUNICIPAL (URBANIZED HIGH DENSITY AREA) 386.63
2 MUNICIPAL POINT SOURCE DISCHARGES 343.29
3 WATERFOWL 186.73
4 COMBINED SEWER OVERFLOWS 162.75
5 RECREATION AND TOURISM ACTIVITIES (OTHER THAN BOATING - SEE 7900) 98.03
6 LAND DISPOSAL 92.99
7 ON-SITE TREATMENT SYSTEMS (SEPTIC SYSTEMS AND SIMILAR DECENTRALIZED SYSTEMS) 92.99
8 MARINAS 86.12
9 INDUSTRIAL POINT SOURCE DISCHARGE 78.10
10 LANDFILLS 16.70

Connecticut

Causes of Impairment

Description of this table
State Cause Name Size of Assessed Waters with Listed Causes of Impairment
Rivers, Streams, Creeks (Miles) Lakes, Ponds, Reservoir (Acres) Bays, Estuaries (Square Miles) Coastal Shorelines (Miles) Oceans, Near Coastal Waters (Square Miles) Wetlands (Acres) Great Lakes Shoreline (Miles) Great Lakes Open Waters (Squar Miles)
ZINC 4.20 .00 .11 .00 .00 .00 .00 .00
LOW DO 12.00 .00 .00 .00 .00 .00 .00 .00
CAUSE UNKNOWN 278.65 .00 .00 .00 .00 .00 .00 .00
PRIORITY ORGANICS .00 2,227.00 13.39 .00 .00 .00 .00 .00
TOTAL SUSPENDED SOLIDS (TSS) .00 2.70 .00 .00 .00 .00 .00 .00
METALS 4.70 .00 .00 .00 .00 .00 .00 .00
NITRATES .60 .00 .00 .00 .00 .00 .00 .00
PATHOGENS 404.40 376.50 191.22 .00 .00 .00 .00 .00
SUSPENDED ALGAE 26.10 1,282.50 .00 .00 .00 .00 .00 .00
UNKNOWN TOXICITY .00 .00 12.34 .00 .00 .00 .00 .00
AMMONIA (UNIONIZED) - TOXIN 1.00 .60 .00 .00 .00 .00 .00 .00
LEAD 2.60 23.60 .45 .00 .00 .00 .00 .00
ORGANIC ENRICHMENT/LOW DO 90.50 1,549.60 225.20 .00 .00 .00 .00 .00
POLYCHLORINATED BIPHENYLS 125.50 3,412.55 9.38 .00 .00 .00 .00 .00
DIOXIN (INCLUDING 2,3,7,8-TCDD) .00 .00 .10 .00 .00 .00 .00 .00
MERCURY 3.40 1,143.75 .40 .00 .00 .00 .00 .00
TOTAL TOXICS 11.80 .00 .00 .00 .00 .00 .00 .00
NON-NATIVE FISH/SHELLFISH/ZOOPLANKTON SPECIES .00 477.30 .00 .00 .00 .00 .00 .00
CADMIUM .00 5.00 .00 .00 .00 .00 .00 .00
RADIATION .73 .00 .00 .00 .00 .00 .00 .00
OIL AND GREASE .00 .00 11.35 .00 .00 .00 .00 .00
FLOW ALTERATION 62.90 .00 4.20 .00 .00 .00 .00 .00
INDICATOR BACTERIA 382.70 376.50 182.68 .00 .00 .00 .00 .00
NONPRIORITY ORGANICS 16.60 .00 5.76 .00 .00 .00 .00 .00
NUTRIENTS 61.80 939.50 232.14 .00 .00 .00 .00 .00
PHOSPHORUS, ELEMENTAL 2.70 .00 .00 .00 .00 .00 .00 .00
SEDIMENTATION/SILTATION 100.10 148.50 .00 .00 .00 .00 .00 .00
NON-NATIVE AQUATIC PLANTS .00 825.10 .00 .00 .00 .00 .00 .00
COPPER 20.00 .60 .11 .00 .00 .00 .00 .00
TURBIDITY 27.50 198.80 .00 .00 .00 .00 .00 .00
PESTICIDES .00 54.00 .00 .00 .00 .00 .00 .00
OTHER HABITAT ALTERATIONS 39.80 107.70 .50 .00 .00 .00 .00 .00
NITROGEN, AMMONIA (TOTAL AMMONIA) 13.60 .00 16.60 .00 .00 .00 .00 .00

Connecticut

Probable Sources Contributing to Impairment

Description of this table
State Source Name Size of Assessed Waters with Probable Sources of Impairment
Rivers, Streams, Creeks (Miles) Lakes, Ponds, Reservoir (Acres) Bays, Estuaries (Square Miles) Coastal Shorelines (Miles) Oceans, Near Coastal Waters (Square Miles) Wetlands (Acres) Great Lakes Shoreline (Miles) Great Lakes Open Waters (Square Miles)
LAND DISPOSAL 6.10 89.90 92.99 .00 .00 .00 .00 .00
OTHER URBAN RUNOFF 3.00 .00 .10 .00 .00 .00 .00 .00
RESOURCE EXTRACTION .00 45.10 .00 .00 .00 .00 .00 .00
CONTAMINATED SEDIMENTS 2.13 3,443.55 13.23 .00 .00 .00 .00 .00
EROSION AND SEDIMENTATION 3.80 238.20 .00 .00 .00 .00 .00 .00
HABITAT MODIFICATION (OTHER THAN HYDROMODIFICATION) 17.90 107.70 .00 .00 .00 .00 .00 .00
SANITARY SEWER OVERFLOWS (COLLECTION SYSTEM FAILURES) 72.10 .00 2.27 .00 .00 .00 .00 .00
RECREATION AND TOURISM ACTIVITIES (OTHER THAN BOATING - SEE 7900) .00 .00 98.03 .00 .00 .00 .00 .00
HYDROPOWER GENERATION 26.30 .00 .00 .00 .00 .00 .00 .00
GROUNDWATER WITHDRAWAL 18.00 .00 .00 .00 .00 .00 .00 .00
SITE CLEARANCE (LAND DEVELOPMENT OR REDEVELOPMENT) 27.60 .00 .00 .00 .00 .00 .00 .00
UPSTREAM IMPOUNDMENTS (E.G., PL-566 NRCS STRUCTURES) 25.70 975.00 .00 .00 .00 .00 .00 .00
CONSTRUCTION 35.90 .00 .00 .00 .00 .00 .00 .00
GOLF COURSES 18.50 .00 .00 .00 .00 .00 .00 .00
LOSS OF RIPARIAN HABITAT 12.60 .00 .00 .00 .00 .00 .00 .00
MINOR MUNICIPAL POINT SOURCE 35.60 .00 .00 .00 .00 .00 .00 .00
ATMOSPHERIC DEPOSITON - TOXICS .00 630.40 .00 .00 .00 .00 .00 .00
ILLICIT CONNECTIONS/HOOK-UPS TO STORM SEWERS 14.90 .00 .00 .00 .00 .00 .00 .00
SOURCES OUTSIDE STATE JURISDICTION OR BORDERS 55.30 3,203.20 .98 .00 .00 .00 .00 .00
SURFACE MINING 5.10 .00 .00 .00 .00 .00 .00 .00
MAJOR INDUSTRIAL POINT SOURCE 1.00 .00 .12 .00 .00 .00 .00 .00
INTENSIVE ANIMAL FEEDING OPERATIONS 18.50 .00 .00 .00 .00 .00 .00 .00
CROP PRODUCTION (CROP LAND OR DRY LAND) 4.70 .00 .00 .00 .00 .00 .00 .00
MUNICIPAL (URBANIZED HIGH DENSITY AREA) 244.65 528.00 386.63 .00 .00 .00 .00 .00
STREAMBANK MODIFICATIONS/DESTABLIZATION 1.70 .00 .00 .00 .00 .00 .00 .00
HIGHWAYS, ROADS, BRIDGES, INFRASTRUCTURE (NEW CONSTRUCTION) 20.40 1,150.90 .97 .00 .00 .00 .00 .00
LANDFILLS 40.90 .60 16.70 .00 .00 .00 .00 .00
AGRICULTURE 35.10 308.80 1.54 .00 .00 .00 .00 .00
CHANNELIZATION 28.80 .00 .00 .00 .00 .00 .00 .00
MAJOR MUNICIPAL POINT SOURCE .30 .00 .00 .00 .00 .00 .00 .00
FLOW ALTERATIONS FROM WATER DIVERSIONS 73.10 .00 4.20 .00 .00 .00 .00 .00
PASTURE GRAZING - RIPARIAN AND/OR UPLAND 8.90 .00 .00 .00 .00 .00 .00 .00
CHANGES IN ORDINARY STRATIFICATION AND BOTTOM WATER HYPOXIA/ANOXIA .00 488.00 .00 .00 .00 .00 .00 .00
DISCHARGES FROM BIOSOLIDS (SLUDGE) STORAGE, APPLICATION OR DISPOSAL .00 .60 .00 .00 .00 .00 .00 .00
DREDGE MINING 4.70 .00 .50 .00 .00 .00 .00 .00
NATURAL SOURCES 8.30 56.00 .40 .00 .00 .00 .00 .00
COMBINED SEWER OVERFLOWS 74.30 .00 162.75 .00 .00 .00 .00 .00
MUNICIPAL POINT SOURCE DISCHARGES 122.00 268.00 343.29 .00 .00 .00 .00 .00
HISTORIC BOTTOM DEPOSITS (NOT SEDIMENT) .00 258.70 .00 .00 .00 .00 .00 .00
LIVESTOCK (GRAZING OR FEEDING OPERATIONS) 17.00 .00 .00 .00 .00 .00 .00 .00
ABOVE GROUND STORAGE TANK LEAKS (TANK FARMS) 7.30 73.00 4.20 .00 .00 .00 .00 .00
HIGHWAY/ROAD/BRIDGE RUNOFF (NON-CONSTRUCTION RELATED) .00 .00 5.63 .00 .00 .00 .00 .00
ON-SITE TREATMENT SYSTEMS (SEPTIC SYSTEMS AND SIMILAR DECENTRALIZED SYSTEMS) 6.10 89.90 92.99 .00 .00 .00 .00 .00
MARINAS .00 .00 86.12 .00 .00 .00 .00 .00
SPILLS FROM TRUCKS OR TRAINS .40 33.00 .44 .00 .00 .00 .00 .00
WATERFOWL 22.00 267.60 186.73 .00 .00 .00 .00 .00
SOURCE UNKNOWN 356.80 1,232.40 13.48 .00 .00 .00 .00 .00
HYDROMODIFICATION 80.90 975.00 4.20 .00 .00 .00 .00 .00
IN-WATER RELEASES .00 .00 8.60 .00 .00 .00 .00 .00
GROUNDWATER LOADINGS 1.00 .00 .00 .00 .00 .00 .00 .00
SPECIALITY CROP PRODUCTION 4.70 .00 .00 .00 .00 .00 .00 .00
UNSPECIFIED NONPOINT SOURCE 10.30 104.10 .00 .00 .00 .00 .00 .00
INDUSTRIAL POINT SOURCE DISCHARGE 98.83 3,360.55 78.10 .00 .00 .00 .00 .00
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