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Assessment Data for the State of Connecticut Year 2004

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The 2004 National Assessment
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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) Inland Lake Shoreline (Miles)
Total Assessed Waters 1,774.24 27,919.30 613.43 .00 .00 .00 .00 .00 .00
Estimated Total Water Size in CT 5,830.00 64,973.00 613.34 Unavailable Unavailable Unavailable Unavailable Unavailable Unavailable
Percent of Waters Assessed 30.43 42.97 100.01 Unavailable Unavailable Unavailable Unavailable Unavailable Unavailable

Assessed Waters of Connecticut by Watershed (8 Digit USGS Cataloging Unit)

 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) Inland Lake Shoreline (Miles)
8-digit HUC Name Not Reported 5.00 2.40 397.72 .00 .00 .00 .00 .00 .00
FARMINGTON 168.43 2,174.50 .00 .00 .00 .00 .00 .00 .00
HOUSATONIC 394.10 14,058.20 3.24 .00 .00 .00 .00 .00 .00
LOWER CONNECTICUT 348.80 3,666.85 12.34 .00 .00 .00 .00 .00 .00
LOWER HUDSON 7.70 95.00 .00 .00 .00 .00 .00 .00 .00
PAWCATUCK-WOOD 32.40 149.70 .42 .00 .00 .00 .00 .00 .00
QUINEBAUG 153.90 3,546.10 .00 .00 .00 .00 .00 .00 .00
QUINNIPIAC 206.00 612.60 129.62 .00 .00 .00 .00 .00 .00
SAUGATUCK 157.60 209.60 33.87 .00 .00 .00 .00 .00 .00
SHETUCKET 212.45 1,972.45 .00 .00 .00 .00 .00 .00 .00
THAMES 87.86 1,431.90 36.22 .00 .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
AESTHETICS 50.20 34.46 5.78 59.76 color.gifcolor.gifcolor.gif
AQUATIC LIFE SUPPORT 1,556.24 63.80 13.08 23.12 color.gifcolor.gifcolor.gif
DRINKING WATER SUPPLY 175.20 77.80 21.58 .63 color.gifcolor.gifcolor.gif
FISH CONSUMPTION 1,773.41 92.74 .07 7.19 color.gifcolor.gifcolor.gif
HYDROPOWER 1.50 100.00 .00 .00 color.gif
PRIMARY CONTACT (RECR) 1,340.61 51.92 17.25 30.84 color.gifcolor.gifcolor.gif
SECONDARY CONTACT (RECR) 3.50 .00 .00 100.00 color.gif
The state assessed 1,774.24 miles of rivers and streams, or 30.43% 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 871.31 49.11
Threatened 291.50 16.43
Impaired 611.43 34.46
Total Miles Assessed 1,774.24 100.00

Connecticut Top Causes of Impairments
for Rivers and Streams

 Description of this table
# State Cause Name Total
Miles
Impaired
1 PATHOGENS 405.50
2 INDICATOR BACTERIA 373.00
3 IMPAIRMENT UNKNOWN 291.40
4 POLYCHLORINATED BIPHENYLS 125.50
5 SEDIMENTATION/SILTATION 98.90
6 ORGANIC ENRICHMENT/LOW DO 92.40
7 FLOW ALTERATION 69.20
8 NUTRIENTS 64.60
9 OTHER HABITAT ALTERATIONS 43.60
10 LOW DO 40.70

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 347.60
2 URBAN RUNOFF/STORM SEWERS 237.30
3 MUNICIPAL POINT SOURCE DISCHARGES 108.50
4 HYDROMODIFICATION 104.80
5 INDUSTRIAL POINT SOURCE DISCHARGE 98.53
6 COMBINED SEWER OVERFLOWS 87.80
7 SANITARY SEWER OVERFLOWS (COLLECTION SYSTEM FAILURES) 72.10
8 FLOW ALTERATIONS FROM WATER DIVERSIONS 69.20
9 AGRICULTURE 65.80
10 SOURCES OUTSIDE STATE JURISTICTION OR BORDERS 59.40

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
AESTHETICS 27,200.70 28.92 61.25 9.83 color.gifcolor.gifcolor.gif
AQUATIC LIFE SUPPORT 27,650.10 43.71 52.56 3.72 color.gifcolor.gifcolor.gif
DRINKING WATER SUPPLY 1,287.10 37.39 62.61 .00 color.gifcolor.gif
FISH CONSUMPTION 27,908.55 85.19 .00 14.81 color.gifcolor.gif
PRIMARY CONTACT (RECR) 26,035.15 41.48 42.55 15.97 color.gifcolor.gifcolor.gif
SECONDARY CONTACT (RECR) 25,055.30 61.63 28.84 9.53 color.gifcolor.gifcolor.gif
The state assessed 27,919.30 acres of lakes, ponds and reservoirs, or 42.97% 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 3,327.90 11.92
Threatened 19,004.80 68.07
Impaired 5,586.60 20.01
Total Acres Assessed 27,919.30 100.00

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 SUSPENDED ALGAE 3,179.80
3 NUTRIENTS 2,892.80
4 NON-NATIVE AQUATIC PLANTS 2,249.10
5 NONNATIVE FISH, SHELLFISH, OR ZOOPLANKTON 2,226.30
6 TASTE AND ODOR 1,900.00
7 FLOW ALTERATION 1,900.00
8 DEBRIS/FLOATABLES/TRASH 1,900.00
9 INDICATOR BACTERIA 1,273.85
10 PATHOGENS 1,273.85

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 JURISTICTION OR BORDERS 3,203.20
4 URBAN RUNOFF/STORM SEWERS 2,591.40
5 HYDROMODIFICATION 2,225.00
6 AGRICULTURE 2,208.80
7 SOURCE UNKNOWN 2,206.10
8 MUNICIPAL POINT SOURCE DISCHARGES 2,168.00
9 HISTORIC BOTTOM DEPOSITS (NOT SEDIMENT) 2,156.00
10 HYDROPOWER GENERATION 1,900.00

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
AQUATIC LIFE SUPPORT 613.43 60.54 .06 39.40 color.gifcolor.gifcolor.gif
FISH CONSUMPTION 613.43 98.48 .00 1.52 color.gifcolor.gif
NONDEGRADATION 613.14 100.00 .00 .00 color.gif
PRIMARY CONTACT (RECR) 609.48 93.69 2.17 4.14 color.gifcolor.gifcolor.gif
SHELLFISHING 377.62 50.41 .00 49.59 color.gifcolor.gif
The state assessed 613.43 square miles of bays and estuaries, or 100.01% 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 209.11 34.09
Threatened 11.34 1.85
Impaired 392.98 64.06
Total Square Miles Assessed 613.43 100.00

Connecticut Top Causes of Impairments
for Bays and Estuaries

 Description of this table
# State Cause Name Total
Square Miles
Impaired
1 ORGANIC ENRICHMENT/LOW DO 237.38
2 NUTRIENTS 234.67
3 AMMONIA (TOTAL) 234.67
4 PATHOGENS 180.75
5 INDICATOR BACTERIA 170.72
6 PRIORITY ORGANICS 13.39
7 UNKNOWN TOXICITY 12.34
8 OIL AND GREASE 11.35
9 POLYCHLORINATED BIPHENYLS 9.38
10 IMPAIRMENT UNKNOWN 4.45

Connecticut Top Probable Sources of Impairments
for Bays and Estuaries

 Description of this table
# State Source Name Total Square Miles Impaired by Source
1 URBAN RUNOFF/STORM SEWERS 382.26
2 MUNICIPAL POINT SOURCE DISCHARGES 343.41
3 ATMOSPHERIC DEPOSITON - TOXICS 232.74
4 MARINAS 192.45
5 WATERFOWL 176.17
6 COMBINED SEWER OVERFLOWS 172.84
7 LAND DISPOSAL 109.76
8 ON-SITE TREATMENT SYSTEMS (SEPTIC SYSTEMS AND SIMILAR DECENCENTRALIZED SYSTEMS) 93.06
9 INDUSTRIAL POINT SOURCE DISCHARGE 78.10
10 SOURCE UNKNOWN 18.51

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 (Square Miles) Inland Lake Shoreline (Miles)
AMMONIA (TOTAL) 14.80 .00 234.67 .00 .00 .00 .00 .00 .00
AMMONIA (UN-IONIZED) 5.00 .60 .00 .00 .00 .00 .00 .00 .00
CADMIUM .00 5.00 .00 .00 .00 .00 .00 .00 .00
CHLORINE 4.00 .00 .00 .00 .00 .00 .00 .00 .00
COPPER 22.90 .60 .11 .00 .00 .00 .00 .00 .00
DEBRIS/FLOATABLES/TRASH .00 1,900.00 .00 .00 .00 .00 .00 .00 .00
DIOXIN (INCLUDING 2,3,7,8-TCDD) .00 .00 .10 .00 .00 .00 .00 .00 .00
FLOW ALTERATION 69.20 1,900.00 4.20 .00 .00 .00 .00 .00 .00
IMPAIRMENT UNKNOWN 291.40 .00 4.45 .00 .00 .00 .00 .00 .00
INDICATOR BACTERIA 373.00 1,273.85 170.72 .00 .00 .00 .00 .00 .00
LEAD 5.50 23.60 .45 .00 .00 .00 .00 .00 .00
LOW DO 40.70 .00 .00 .00 .00 .00 .00 .00 .00
MERCURY 3.40 818.75 .40 .00 .00 .00 .00 .00 .00
METALS 27.80 821.35 .55 .00 .00 .00 .00 .00 .00
NITRATES .60 .00 .00 .00 .00 .00 .00 .00 .00
NON-NATIVE AQUATIC PLANTS .00 2,249.10 .00 .00 .00 .00 .00 .00 .00
NONNATIVE FISH, SHELLFISH, OR ZOOPLANKTON .00 2,226.30 .00 .00 .00 .00 .00 .00 .00
NONPRIORITY ORGANICS 16.30 .00 .44 .00 .00 .00 .00 .00 .00
NUTRIENTS 64.60 2,892.80 234.67 .00 .00 .00 .00 .00 .00
OIL AND GREASE .30 .00 11.35 .00 .00 .00 .00 .00 .00
ORGANIC ENRICHMENT/LOW DO 92.40 896.90 237.38 .00 .00 .00 .00 .00 .00
ORGANINC ENRICHMENT .30 .00 .00 .00 .00 .00 .00 .00 .00
OTHER HABITAT ALTERATIONS 43.60 105.00 .50 .00 .00 .00 .00 .00 .00
PATHOGENS 405.50 1,273.85 180.75 .00 .00 .00 .00 .00 .00
PESTICIDES .00 54.00 .00 .00 .00 .00 .00 .00 .00
PHOSPHORUS, ELEMENTAL 2.80 .00 .00 .00 .00 .00 .00 .00 .00
POLYCHLORINATED BIPHENYLS 125.50 3,412.55 9.38 .00 .00 .00 .00 .00 .00
PRIORITY ORGANICS .10 2.00 13.39 .00 .00 .00 .00 .00 .00
SALINITY 1.60 .00 .00 .00 .00 .00 .00 .00 .00
SEDIMENTATION/SILTATION 98.90 155.30 .00 .00 .00 .00 .00 .00 .00
SULFATES .10 .00 .00 .00 .00 .00 .00 .00 .00
SUSPENDED ALGAE 30.70 3,179.80 .00 .00 .00 .00 .00 .00 .00
TASTE AND ODOR .00 1,900.00 .00 .00 .00 .00 .00 .00 .00
TEMPERATURE, WATER 1.70 .00 .00 .00 .00 .00 .00 .00 .00
TOTAL SUSPENDED SOLIDS (TSS) .00 9.50 .00 .00 .00 .00 .00 .00 .00
TOTAL TOXICS 11.80 .00 .00 .00 .00 .00 .00 .00 .00
TURBIDITY 28.00 205.60 .00 .00 .00 .00 .00 .00 .00
UNKNOWN TOXICITY 3.30 .00 12.34 .00 .00 .00 .00 .00 .00
ZINC 4.60 .00 .11 .00 .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) Inland Lake Shoreline (Miles)
ABOVE GROUND STORAGE TANK LEAKS (TANK FARMS) 7.60 73.00 4.20 .00 .00 .00 .00 .00 .00
AGRICULTURE 65.80 2,208.80 1.54 .00 .00 .00 .00 .00 .00
ANIMAL FEEDING OPERATIONS (NPS) 18.40 .00 .00 .00 .00 .00 .00 .00 .00
ATMOSPHERIC DEPOSITON - TOXICS .00 630.40 232.74 .00 .00 .00 .00 .00 .00
CHANGES IN ORDINARY STRATIFICATION AND BOTTOM WATER HYPOXIA/ANOXIA .00 346.00 .00 .00 .00 .00 .00 .00 .00
CHANNELIZATION 29.50 .00 .00 .00 .00 .00 .00 .00 .00
COMBINED SEWER OVERFLOWS 87.80 .00 172.84 .00 .00 .00 .00 .00 .00
CONSTRUCTION 35.50 .00 .00 .00 .00 .00 .00 .00 .00
CONTAMINATED SEDIMENTS 2.13 3,443.55 13.23 .00 .00 .00 .00 .00 .00
CROP PRODUCTION (CROP LAND OR DRY LAND) 5.00 .00 .00 .00 .00 .00 .00 .00 .00
DISCHARGES FROM BIOSOLIDS (SLUDGE) STORAGE, APPLICATION OR DISPOSAL .00 .60 .00 .00 .00 .00 .00 .00 .00
DREDGE MINING 4.70 .00 .50 .00 .00 .00 .00 .00 .00
EROSION AND SEDIMENTATION 3.80 245.00 .00 .00 .00 .00 .00 .00 .00
FLOW ALTERATIONS FROM WATER DIVERSIONS 69.20 .00 .00 .00 .00 .00 .00 .00 .00
GOLF COURSES 18.50 .00 .00 .00 .00 .00 .00 .00 .00
GROUNDWATER LOADINGS 1.00 .00 .00 .00 .00 .00 .00 .00 .00
GROUNDWATER WITHDRAWAL 19.40 .00 .00 .00 .00 .00 .00 .00 .00
HABITAT MODIFICATION - OTHER THAN HYDROMODIFICATION 22.70 508.80 .00 .00 .00 .00 .00 .00 .00
HIGHWAYS, ROADS, BRIDGES, INFRASTURCTURE (NEW CONSTRUCTION) 2.20 258.50 6.60 .00 .00 .00 .00 .00 .00
HISTORIC BOTTOM DEPOSITS (NOT SEDIMENT) .00 2,156.00 .00 .00 .00 .00 .00 .00 .00
HYDROMODIFICATION 104.80 2,225.00 .00 .00 .00 .00 .00 .00 .00
HYDROPOWER GENERATION 26.30 1,900.00 .00 .00 .00 .00 .00 .00 .00
INDUSTRIAL POINT SOURCE DISCHARGE 98.53 3,360.55 78.10 .00 .00 .00 .00 .00 .00
LAND DISPOSAL 47.20 90.50 109.76 .00 .00 .00 .00 .00 .00
LANDFILLS 40.50 .60 16.70 .00 .00 .00 .00 .00 .00
LIVESTOCK (GRAZING OR FEEDING OPERATIONS) 17.00 .00 .00 .00 .00 .00 .00 .00 .00
LOSS OF RIPARIAN HABITAT 15.30 .00 .00 .00 .00 .00 .00 .00 .00
MAJOR MUNICIPAL POINT SOURCE .30 .00 .00 .00 .00 .00 .00 .00 .00
MARINAS .00 .00 192.45 .00 .00 .00 .00 .00 .00
MINOR MUNICIPAL POINT SOURCE 35.60 .00 .00 .00 .00 .00 .00 .00 .00
MUNICIPAL POINT SOURCE DISCHARGES 108.50 2,168.00 343.41 .00 .00 .00 .00 .00 .00
NATURAL SOURCES 10.10 56.00 .40 .00 .00 .00 .00 .00 .00
NON-POINT SOURCE 10.30 139.60 .00 .00 .00 .00 .00 .00 .00
ON-SITE TREATMENT SYSTEMS (SEPTIC SYSTEMS AND SIMILAR DECENCENTRALIZED SYSTEMS) 6.70 89.90 93.06 .00 .00 .00 .00 .00 .00
RECREATION AND TOURISM ACTIVITIES (OTHER THAN BOATING - SEE 7900) 18.50 .00 .00 .00 .00 .00 .00 .00 .00
RESOURCE EXTRACTION 13.20 45.10 .50 .00 .00 .00 .00 .00 .00
SANITARY SEWER OVERFLOWS (COLLECTION SYSTEM FAILURES) 72.10 .00 2.40 .00 .00 .00 .00 .00 .00
SITE CLEARANCE (LAND DEVELOPMENT OR REDEVELOPMENT) 35.50 .00 .00 .00 .00 .00 .00 .00 .00
SOURCE UNKNOWN 347.60 2,206.10 18.51 .00 .00 .00 .00 .00 .00
SOURCES OUTSIDE STATE JURISTICTION OR BORDERS 59.40 3,203.20 1.07 .00 .00 .00 .00 .00 .00
SPILLS FROM TRUCKS OR TRAINS 4.70 33.00 .44 .00 .00 .00 .00 .00 .00
STREAMBANK MODIFICATIONS/DESTABLIZATION 1.70 9.50 .00 .00 .00 .00 .00 .00 .00
SURFACE MINING 8.50 .00 .00 .00 .00 .00 .00 .00 .00
UPSTREAM IMPOUNDMENTS (E.G., PL-566 NRCS STRUCTURES) 27.70 325.00 .00 .00 .00 .00 .00 .00 .00
URBAN RUNOFF/STORM SEWERS 237.30 2,591.40 382.26 .00 .00 .00 .00 .00 .00
WATERFOWL 21.50 99.45 176.17 .00 .00 .00 .00 .00 .00
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