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Connecticut State Report

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Water Quality Data Available for this Watershed

Connecticut, Thames Watershed


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Assessment Summary for Reporting Year 2010
Connecticut, Thames Watershed

Description of this table
Click here to list Threatened and Impaired Waters Only
NOTE: Click on the underlined "Waterbody Name" to view a Waterbody report.
Waterbody Name Waterbody ID Location Map Waterbody Type Size Units Status State TMDL Development Status
Amos Lake (Preston) CT3002-02-1-L2_01 East Of Rte 164, Preston. Waterbody Map Freshwater Lake 112.4 Acres Impaired TMDL needed
Avery Pond (Preston) CT3002-04-1-L1_01 East Of Rte 164, North Of Rte 2, Preston. Waterbody Map Freshwater Lake 45.6 Acres Good  
Bentley Brook-01 CT3900-09_01 From Mouth At Confluence With Yantic River (Just Ds Of Route 2 Crossing, On Bozrah/Norwich Town Border), Us To Headwaters, Gager Road, Bozrah. Waterbody Map River 2.2 Miles Good  
Bog Meadow Reservoir (Norwich) CT3900-11-1-L1_01 Norwich Waterbody Map Freshwater Lake 91.2 Acres Good  
Bride Brook-01 CT2206-00_01 From Head Of Estuary (Salt Water Limit, Just Ds Of Route 156 Crossing), Us To Bride Lake Outlet Dam (Just Us Of North Bride Brook Road), East Lyme. Waterbody Map River .7 Miles Impaired TMDL needed
Bride Brook-02 CT2206-00_02 From Inlet To Bride Lake (Northwest Portion, Just Ds Of North Bride Brook Road Crossing), Us To Headwaters (Marsh On South Side Of Route 1), East Lyme. Waterbody Map River 2.1 Miles Impaired TMDL needed
Copps Brook-01 CT2102-00_01 From Mouth At Quiambog Cove (Parallel To Cove Road), Us To Palmer (Mystic) Reservoir Outlet Dam (Just Us Of Jerry Brown Road Crossing), Stonington. Waterbody Map River .8 Miles Impaired TMDL needed
Copps Brook-02 CT2102-00_02 From Inlet To Palmer (Deans/Mystic) Reservoir (Just Ds Of Pequot Trail (Route 234) Road Crossing), Stonington, Us To Headwaters (Just Us Of Mystic Road (Route 201) Crossing, North Stonington. Waterbody Map River 4.3 Miles Good  
Dodge Pond (East Lyme) CT2205-02-1-L1_01 East Lyme; Near Niantic Village Center, East Of Rte 161, North Of Rte 156. Waterbody Map Freshwater Lake 29.6 Acres Impaired TMDL needed
Fenger Brook-01 CT2000-30_01 From Mouth At Head Of Tide, Alewife Cove (Just Ds Of Niles Hill Road (Route 213) Crossing), Us To Headwaters (Southeast Of Clark Lane And Chester Street Intersection), Waterford. Waterbody Map River 3.5 Miles Impaired TMDL needed
Fitchville Pond (Bozrah) CT3900-00-4-L1_01 Split By Rte 2 In Bozrah, Impoundment Of Yantic River. Waterbody Map Freshwater Lake 58.5 Acres Good  
Flat Brook (Ledyard)-01 CT3000-08_01 From Mouth At Confluence With Thames River (Inlet To Long Cove, North Of Navy Base) Gales Ferry/Ledyard, Us To Headwaters At Unnamed Pond, Groton (Brook Runs North). Waterbody Map River 1.1 Miles Impaired TMDL needed
Gardner Brook-01 CT3906-00_01 From Mouth At Confluence With Yantic River (Inlet To Fitchville Pond, Southeast Side Parallell To Route 163), Us To Gardner Lake Outlet Dam (Just Us Of Lake Road Crossing), Bozrah. Waterbody Map River 4.8 Miles Good  
Gardner Lake (Salem/Montville/Bozrah) CT3906-00-1-L1_01 At Junction Of Salem, Montville And Bozrah. Waterbody Map Freshwater Lake 527.3 Acres Good  
Gorton Pond (East Lyme) CT2205-00-1-L3_01 East Lyme. Impoundment Of Pataganset River. Waterbody Map Freshwater Lake 52.4 Acres Good  
Groton (Poquonnock) Reservoir (Groton) CT2107-00-1-L6_01 Groton Waterbody Map Freshwater Lake 194.7 Acres Good  
Kahn Brook-01 CT3900-07_01 From Mouth At Confluence With Yantic River (Just Ds Of Fitchville Road Crossing), Us To Chicken Farm Road Crossing, Bozrah. Waterbody Map River .6 Miles Impaired TMDL needed
Konomoc, Lake (Waterford/Montville) CT2203-00-1-L2_01 Waterford Waterbody Map Freshwater Lake 288.7 Acres Good  
Lake Of Isles (North Stonington) CT3002-06-1-L1_01 Near Western Border Of North Stonington, North Of Rte 2. Waterbody Map Freshwater Lake 91.3 Acres Good  
Lantern Hill Pond (Ledyard/North Stonington) CT2104-00-1-L1_01 Border Of Ledyard And North Stonington; Now Part Of Mashentucket Reservation. Waterbody Map Freshwater Lake 20.1 Acres Good  
Latimer Brook-01 CT2202-00_01 From Mouth At Confluence With Niantic River (Head Of Tide At Banning Cove Inlet, Just Ds Of Route 1 Crossing, South Side Of I95, East Of Exit 75), Us To Confluence With Cranberry Meadow Brook (Parallel With Route 161), East Lyme Waterbody Map River 4.2 Miles Impaired TMDL needed
Latimer Brook-02 CT2202-00_02 From Confluence With Cranberry Meadow Brook (Parallel With Route 161), East Lyme, Us To Beckwith Pond Outlet Dam (Boundary Of Drinking Water Watershed, Just Us Of Route 85 Crossing), Montville. Waterbody Map River 3.4 Miles Good  
Latimer Brook-03 CT2202-00_03 From Beckwith Pond Inlet (In Marsh On Northern Side), Us To Headwaters At Barnes Reservoir Outlet Dam, Montville/Salem. Waterbody Map River 1.3 Miles Good  
Lis Eb Inner - Alewife Cove, Waterford/New London CT-E1_017 See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Alewife Cove From Outlet At Waterford Beach Park Picnic Area, Us To Saltwater Limit At Niles Hill Road Crossing, Waterford. Waterbody Map Estuary .1 Square Miles Impaired TMDL needed
Lis Eb Inner - Baker Cove, Groton CT-E1_013 See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Baker Cove From Avery Point And Tip Of Pine Island, To Mouth Of Poquonuck River (South Of Groton-New London Airport), Groton. Waterbody Map Estuary .3 Square Miles Impaired TMDL needed
Lis Eb Inner - Beebe Cove (Mystic Harbor), Groton CT-E1_009 See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Beebe Cove (Mystic Harbor) Waters West Of Two Rr Crossings Along Shore, Groton. Waterbody Map Estuary .2 Square Miles Impaired TMDL needed
Lis Eb Inner - Bride Brook, East Lyme CT-E1_022 See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Bride Brook From Outlet At Rr Crossing, Eastern End Of Rocky Neck State Park Beach, Us To Saltwater Limit At Route 156 Crossing, East Lyme. Waterbody Map Estuary .0 Square Miles Impaired TMDL needed
Lis Eb Inner - Fourmile River (Mouth), Old Lyme CT-E1_023 See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Fourmile River From Outlet At Rr Crossing, Western End Of Rocky Neck State Park Beach, Us To Saltwater Limit At Route 156 Crossing, Old Lyme. Waterbody Map Estuary .0 Square Miles Impaired TMDL needed
Lis Eb Inner - Goshen Cove, Waterford CT-E1_018-SB See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Goshen Cove From Outlet At Goshen Point (Includes Western Side Of Harkness Memorial State Park), Us To Saltwater Limit At Route 213 Crossing, Waterford. Waterbody Map Estuary .0 Square Miles Good  
Lis Eb Inner - Inner Quiambaug Cove, Stonington CT-E1_006 See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Inner Quiambaug Cove From Rr Crossing, Us To Saltwater Limit, Above Route 1 Crossing, Adjacent To Cove Road, Stonington. Waterbody Map Estuary .1 Square Miles Impaired TMDL needed
Lis Eb Inner - Inner Stonongton Harbor, Stonington CT-E1_005 See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Inner Stonington Harbor From Sb/Sa Water Quality Boundary At Rr Crossing, Us To Saltwater Limit Near Route 1 Crossing, Stonington. Waterbody Map Estuary .2 Square Miles Impaired TMDL needed
Lis Eb Inner - Inner Wequetequock Cove, Stonington CT-E1_003 See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Inner Wequetequock Cove From Rr Crossing Us To Saltwater Limit, In Two Lopes Adjacent To Route 1, Stonington. Waterbody Map Estuary .1 Square Miles Impaired TMDL needed
Lis Eb Inner - Jordan Cove, Waterford CT-E1_019 See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Jordan Cove From Outlet At Pleasure Beach, Us Past Rr Crossing, To Saltwater Limit At Outlet Dam Of Jordan Mill Pond, Adjacent To Route 156, Waterford. Waterbody Map Estuary .2 Square Miles Impaired TMDL needed
Lis Eb Inner - Mumford Cove (Inner), Groton CT-E1_011-SB See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Inner Mumford Cove Along East Side Of Bluff Point State Park Shore, And North Of Groton Long Point To Saltwater Limit Near Rr Crossing, Groton. Waterbody Map Estuary .2 Square Miles Impaired TMDL needed
Lis Eb Inner - Mystic Harbor, Groton CT-E1_008-SB See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Mystic Harbor From Morgan Point To Rr Crossing At Mouth Of Mystic River (Includes Waters North Of Mason Island), Groton. Waterbody Map Estuary 1.0 Square Miles Good  
Lis Eb Inner - Mystic River (Mouth), Stonington CT-E1_007-SB See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Mouth Of Mystic River Estuary From Rr Crossing, Us To Saltwater Limit, Above Route 95 Crossing, Adjacent To Mill Street, Stonington (Old Mystic). Waterbody Map Estuary .5 Square Miles Good  
Lis Eb Inner - Niantic River (Mouth), Niantic CT-E1_020 See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Niantic River (Inner Niantic Bay) From Outlet At Route 156 And Rr Crossing, Us To Saltwater Limit In Banning Cove (Between Route 1 Crossing And I95/I395), East Lyme/Waterford. Waterbody Map Estuary 1.3 Square Miles Impaired TMDL needed
Lis Eb Inner - Outer Stonington Harbor, Stonington CT-E1_004-SB See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Outer Stonington Harbor From Sb/Sa Water Quality Boundary Near Wamphassuc Point To Offshore Stonington Point, Us To Rr Crossing, Stonington. Waterbody Map Estuary .6 Square Miles Good  
Lis Eb Inner - Palmer Cove (Inner), Groton CT-E1_010 See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Inner Palmer Cove Waters From North Side Of Groton Long Point Road Crossing, Past Rr Crossings To Saltwater Limit, Groton. Waterbody Map Estuary .1 Square Miles Impaired TMDL needed
Lis Eb Inner - Pattagansett Rvr (Mouth), East Lyme CT-E1_021 See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Pattagansett River From Outlet At Rr Crossing, Us To Saltwater Limit At Route 156 Crossing, East Lyme. Waterbody Map Estuary .0 Square Miles Impaired TMDL needed
Lis Eb Inner - Poquonuck River (Mouth), Groton CT-E1_012 See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Poquonuck River From Mouth At Baker Cove (Along East Of Groton-New London Airport), Us To Saltwater Limit Just Us Of Rr Crossing, Groton. Waterbody Map Estuary .4 Square Miles Impaired TMDL needed
Lis Eb Inner - Thames River (Middle), Ledyard CT-E1_015-SB See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Thames River From I95 Crossing, Us To Just Below Outlet Of Poquetanuck Cove (Near Walden Island), And Adjacent To Route 12 At Cardinal Lane Intersection, Ledyard. Waterbody Map Estuary 3.3 Square Miles Impaired TMDL needed
Lis Eb Inner - Thames River (Mouth), New London CT-E1_014-SB See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Mouth Of Thames River From Eastern Point (North Of Avery Point), Us To I95 Crossing (Includes Inner New London Harbor), Groton. Waterbody Map Estuary 2.0 Square Miles Impaired TMDL needed
Lis Eb Inner - Thames River (Upper), Norwich CT-E1_016-SB See Map For Boundaries. Eastern Portion Of Lis, Inner Estuary, Thames River From Just Below Outlet Of Poquetanuck Cove (Near Walden Island), Adjacent To Route 12 At Cardinal Lane Intersection, Us To First Dams In Yantic And Shetucket Rivers, Norwich. Waterbody Map Estuary 1.6 Square Miles Impaired TMDL needed
Lis Eb Midshore - Old Saybrook, Ct River CT-E3_009-SB See Map For Boundaries. Eastern Portion Of Lis From Sb/Sa Water Quality Boundary, Lynde Point In Ct River Mouth Old Saybrook, To Approximately 1000 Ft Offshore East Of White Sands Beach, Old Lyme (Mouth Of Connecticut River). Waterbody Map Estuary 2.9 Square Miles Good  
Lis Eb Midshore - Waterford, Thames River CT-E3_005-SB See Map For Boundaries. Eastern Portion Of Lis From Sb/Sa Water Quality Boundary, Approximately 1000 Ft Offshore Of Magonk Point, Waterford To Bushypoint, Groton, Out To Sb/Sa Water Quality Boundary (Thames River Mouth). Waterbody Map Estuary 5.3 Square Miles Impaired TMDL needed
Lis Eb Shore - Bluff Point, Groton CT-E2_008 See Map For Boundaries. Eastern Portion Of Lis From Sb/Sa Water Quality Boundary At Bushy Point Beach To Mumford Point, Out Approximately 1000 Ft Offshore. Waterbody Map Estuary .2 Square Miles Impaired TMDL needed
Lis Eb Shore - Ct River Mouth (East), Old Lyme CT-E2_019-SB See Map For Boundaries. Eastern Portion Of Lis From Griswold Point To Sb/Sa Water Quality Boundary At Hawks Nest Beach Area (Includes White Sands Beach), Out Approximately 1000 Ft Offshore. (Sb Water) Waterbody Map Estuary .4 Square Miles Good  
Lis Eb Shore - Mouth Mystic River, Stonington CT-E2_005 See Map For Boundaries. Eastern Portion Of Lis From Western Most Tip Of Mason Island Along Sb/Sa Water Quality Boundary To Eastern Most Tip Of Mason Island, Out Approximately 1000 Ft Offshore. Waterbody Map Estuary .4 Square Miles Impaired TMDL needed
Lis Eb Shore - Niantic Bay (Black Pt), East Lyme CT-E2_015 See Map For Boundaries. Eastern Portion Of Lis From Point East Of Griswald Island, Past Black Point To Pond Point In Niantic Bay, Out Approximately 1000 Ft Offshore. Waterbody Map Estuary .6 Square Miles Impaired TMDL needed
Lis Eb Shore - Niantic Bay (East), Waterford CT-E2_013 See Map For Boundaries. Eastern Portion Of Lis From Smith Avenue At Junction With Route 156 To Millstone Point, Out Approximately 1000 Ft Offshore. Waters Adjacent To Millstone Power Plant. Waterbody Map Estuary .4 Square Miles Impaired TMDL needed
Lis Eb Shore - Niantic Bay (West), East Lyme CT-E2_014 See Map For Boundaries. Eastern Portion Of Lis From Pond Point To Smith Avenue At Junction With Route 156, Out Approximately 1000 Ft Offshore. Waters Adjacent To Millstone Power Plant. Waterbody Map Estuary .3 Square Miles Impaired TMDL needed
Lis Eb Shore - Outer Jordan Cove, Waterford CT-E2_012 See Map For Boundaries. Eastern Portion Of Lis From Millstone Point To Sb/Sa Water Quality Boundary At Magonk Point, Out Approximately 1000 Ft Offshore. Waters Adjacent To Millstone Power Plant. Waterbody Map Estuary .5 Square Miles Impaired TMDL needed
Lis Eb Shore - Outer Mumford Cove, Groton CT-E2_007 See Map For Boundaries. Eastern Portion Of Lis From Mumford Point To Eastern Most Tip Of Groton Long Point (Includes Outer Mumford Cove And All Of Venetian Harbor), Out Approximately 1000 Ft Offshore. Waterbody Map Estuary .6 Square Miles Impaired TMDL needed
Lis Eb Shore - Outer Quiambaug Cove, Stonington CT-E2_003 See Map For Boundaries. Eastern Portion Of Lis From Mouth Of Inner Quiambaug Cove At Rr Crossing To Sb/Sa Water Quality Boundary At Mouth Of Stonington Harbor, Out Approximately 1000 Ft Offshore. Waterbody Map Estuary .4 Square Miles Impaired TMDL needed
Lis Eb Shore - Pattagansett River Mouth, East Lyme CT-E2_016 See Map For Boundaries. Eastern Portion Of Lis From Seal Rock (Great Neck) To Point East Of Griswald Island (Entire Mouth Of Pattagansett River, Including Area Around Watts Island), Out Approximately 1000 Ft Offshore. Waterbody Map Estuary .3 Square Miles Impaired TMDL needed
Lis Eb Shore - Rocky Neck (Fourmile Rvr), Old Lyme CT-E2_017 See Map For Boundaries. Eastern Portion Of Lis From Hatchett Point To Seal Rock (Great Neck) Includes Rocky Neck State Park Beach, Out Approximately 1000 Ft Offshore. Waterbody Map Estuary .5 Square Miles Impaired TMDL needed
Lis Eb Shore - Soundview Beach, Old Lyme CT-E2_018 See Map For Boundaries. Eastern Portion Of Lis From Sb/Sa Water Quality Boundary At Hawks Nest Beach Area To Hatchett Point (Includes Soundview Beach), Out Approximately 1000 Ft Offshore. Waterbody Map Estuary .3 Square Miles Impaired TMDL needed
Lis Eb Shore - Stonington Point, Stonington CT-E2_002 See Map For Boundaries. Eastern Portion Of Lis From Stonington Point To Rr Crossing On West Side Of Wequetequock Cove, Out Approximately 1000 Ft Offshore. Waterbody Map Estuary .7 Square Miles Impaired TMDL needed
Lis Eb Shore - Thames River Mouth (East), Groton CT-E2_009-SB See Map For Boundaries. Eastern Portion Of Lis From Eastern Point In Mouth Of Thames River To Sb/Sa Water Quality Boundary At Bushy Point Beach, Out Approximately 1000 Ft Offshore. Waterbody Map Estuary .4 Square Miles Impaired TMDL needed
Lis Eb Shore - Thames Rvr Mouth (West), New London CT-E2_010-SB See Map For Boundaries. Eastern Portion Of Lis From Mouth Of Alewife Cove To Quinnipeag Rocks Along Western Shore Of Thames River Mouth, Out Approximately 1000 Ft Offshore (Sb Water Quality). Waterbody Map Estuary .3 Square Miles Impaired TMDL needed
Lis Eb Shore - Thames Rvr Mouth (West), Waterford CT-E2_011-SB See Map For Boundaries. Eastern Portion Of Lis From Magonk Point To Mouth Of Alewife Cove, Out Approximately 1000 Ft Offshore (Sb Water Quality). Waterbody Map Estuary .5 Square Miles Impaired TMDL needed
Lis Eb Shore - Wequetequock Cove, Stonington CT-E2_001 See Map For Boundaries. Eastern Portion Of Lis From Rr Crossing On East Side Of Wequetequock Cove To Mouth Of Pawcatuck River, Out Approximately 1000 Ft Offshore (Little Narragansett Bay). Waterbody Map Estuary .6 Square Miles Impaired TMDL needed
Lis Eb Shore - West Cove (Groton Long Pt), Groton CT-E2_006 See Map For Boundaries. Eastern Portion Of Lis From Tip Of Groton Long Point To Morgan Point At Sb/Sa Water Quality Boundary For Mystic River Mouth, Out Approximately 1000 Ft Offshore. Waterbody Map Estuary .4 Square Miles Impaired TMDL needed
Lis Eb Shore - Wilcox Cove (Mason Is.), Stonington CT-E2_004 See Map For Boundaries. Eastern Portion Of Lis From Tip Of Mason Island To Mouth Of Inner Quiambaug Cove, Out Approximately 1000 Ft Offshore. Waterbody Map Estuary .7 Square Miles Impaired TMDL needed
Long Pond (Ledyard/North Stonington) CT2104-00-1-L2_01 Ledyard, North Stonington Border. Waterbody Map Freshwater Lake 111.3 Acres Good  
Morgan Pond (Ledyard) CT2107-00-1-L1_01 South Side Of Sandy Hollow Road, West Of Route 117 Intersection, Ledyard. Waterbody Map Freshwater Lake 146.2 Acres Good  
Oxoboxo Brook-01 CT3004-00_01 From Mouth At Head Of Tide (Inlet To Gay Cemetery Pond, Horton Cove, Thames River), Us To Wheeler Pond Outlet Dam, Montville. (Segment Includes Rockland Pond) Waterbody Map River 2.6 Miles Impaired TMDL needed
Oxoboxo Brook-02 CT3004-00_02 From Inlet To Wheeler Pond (Northwestern Portion, Ds Of Meeting House Lane Road Crossing), Us To Oxoboxo Lake Outlet Dam. (Includes Scholfield Pond) Waterbody Map River 3.0 Miles Good  
Pataganset Lake (East Lyme) CT2205-00-1-L2_01 East Lyme, Pataganset River System. Waterbody Map Freshwater Lake 125.7 Acres Good  
Pattagansett River-01 CT2205-00_01 From Head Of Tide, Just Ds Of Route 156 Crossing, Us To Gorton Pond Outlet Dam (Just Us Of Roxbury Road Crossing, East Of Route 161 Intersection), East Lyme. Waterbody Map River 1.2 Miles Good  
Pattagansett River-02 CT2205-00_02 From Inlet To Gorton Pond (Northern Side In Marsh, Just Ds Of I95 Crossing), Us To Pattagansett Lake Outlet Dam (Just Us Of Route 1 Crossing), East Lyme. Waterbody Map River 1.9 Miles Good  
Pattagansett River-03 CT2205-00_03 From Inlet To Pattagansett Lake (Northwest Portion Of Lake), Us To Powers Lake Outlet Dam (Just Us Of Upper Pattagansett Road Crossing), East Lyme. Waterbody Map River 1.0 Miles Good  
Pease Brook-01 CT3905-00_01 From Mouth At Confluence With Yantic River, Bozrah, Us To Headwaters (Just Us Of Burnham Road Crossing, Lebanon Waterbody Map River 9.6 Miles Good  
Poquetanuck And Hewitt Brooks-01 CT3003-00_01 From Mouth Of Poquetanuck Brook (At Confluence With Thames River, Inlet To Poquetanuck Cove, Just Ds Of Poquetanuck Road (Route 2a) Crossing), Us To Confluence With Hewitt Brook, Then Continues Us In Hewitt Brook To Hallville Pond Outlet Dam. Waterbody Map River 1.7 Miles Good  
Powers Lake (East Lyme) CT2205-00-1-L1_01 East Lyme, Headwaters Of Pataganset River. Waterbody Map Freshwater Lake 146.5 Acres Good  
Red Cedar Lake (Lebanon) CT3900-01-1-L1_01 South Corner Of Lebanon. Waterbody Map Freshwater Lake 132.9 Acres Good  
Seth Williams Brook-01 CT2103-00_01 From Mouth At Whitford Brook On Ledyard/Stonington Town Line, Us To Shewville Road Crossing, Ledyard. Waterbody Map River .4 Miles Good  
Seth Williams Brook-02 CT2103-00_02 From Shewville Road Crossong, Us To Highlands Potw (Ds Of Town Farm Road, Parallel To Shewville Road), Ledyard. Waterbody Map River .5 Miles Good  
Seth Williams Brook-03 CT2103-00_03 From Highlands Potw (Ds Of Town Farm Road Crossing, Parallel To Shewville Road), Us To Headwaters (Us Of Shewville Road Crossing, South Of Route 214 Intersection), Ledyard. Waterbody Map River 2.1 Miles Good  
Sherman Brook-01 CT3903-00_01 From Mouth At Confluence With Deep River, Above Yantic River, Lebanon, Us To Headwaters (Just Us Of Lebanon Avenue (Route 16 Crossing), Colchester. (Segment Includes Sherman Pond). Waterbody Map River 5.0 Miles Good  
Spaulding Pond (Norwich) CT3800-00-6+L3_01 Mohegan Park, Norwich (Mohegan Park Rd) Waterbody Map Freshwater Lake 14.3 Acres Impaired TMDL needed
Susquetonscut Brook-01 CT3907-00_01 From Mouth At Confluence With Yantic River, Bozrah/Norwich Town Border (Just Ds Of Railroad Crossing), Us To Headwaters (Just Us Of Bender Road Crossing, Along South Side Of Beaumont Highway And Rafferty Road Intersection, Lebanon. Waterbody Map River 13.6 Miles Good  
Trading Cove Brook-01 CT3001-00_01 From Head Of Tide At Confluence With Thames River (Inlet To Trading Cove, Just Ds From Route 32 Crossing), Norwich/Montville Town Line, Us To Headwaters (In Marsh Just Us Of Bozrah Road (Route 163) Crossing), Montville. Waterbody Map River 7.2 Miles Good  
Unnamed Trib To Copps Brook-01 CT2102-00-trib_01 From Mouth At Copps Brook, Just Us Of Quiambog Cove (Parallel To Cove Road), Us To Headwaters Near Jerry Brown Road, Stonington (Intermittent). Waterbody Map River .7 Miles Impaired Non-pollutant impairment
Whitford Brook-01 CT2104-00_01 From Mouth At Head Of Mystic River Estuary (At Confluence With Haleys Brook, Above Mystic River, Ds Of Route 27 Crossing), Stonington/Groton Town Line, Us To Area East Of The Shewville Road And Gallup Hill Road Intersection, Ledyard/Stonington Town Line. Waterbody Map River 1.6 Miles Good  
Whitford Brook-02a CT2104-00_02a From Area East Of The Shewville Road And Gallup Hill Road Intersection, Ledyard/Stonington Town Line, Us To Entrance Of "Lantern Hill" Wellfield (West Of Lantern Hill Road, In Marsh Parallel With Stony Pond), Ledyard/Stonington Town Line. Waterbody Map River .7 Miles Impaired Non-pollutant impairment
Whitford Brook-02b CT2104-00_02b From Entrance Of "Lantern Hill" Wellfield (West Of Lantern Hill Road, In Marsh Parallel With Stony Pond), Ledyard/Stonington Town Line, Us To Confluence With Seth Williams Brook, Ledyard/Stonington Town Line. Waterbody Map River .4 Miles Good  
Whitford Brook-03 CT2104-00_03 From Confluence With Seth Williams Brook, Us To Whitford Pond Outlet Dam (Just Us Of Whitford Road Crossing), Ledyard/Stonington Town Line. Waterbody Map River .3 Miles Good  
Whitford Brook-04 CT2104-00_04 From Inlet To Whitford Pond (Northeast Portion Of Pond), Ledyard/Stonington Town Line, Us To Long Pond Outlet Dam (Just Us Of Lantern Hill Road Crossing), Ledyard. Waterbody Map River .9 Miles Good  
Williams Pond (Lebanon) CT3902-00-1-L1_01 Lebanon Waterbody Map Freshwater Lake 250.3 Acres Good  
Yantic River-01 CT3900-00_01 From Vermont Railroad Crossing (Just Us Of Falls Mill Lower Dam), Norwich, Us To Fitchville Pond Outlet Dam (Just Us Of Fitchville Road Crossing), Bozrah. Waterbody Map River 6.5 Miles Good  
Yantic River-02 CT3900-00_02 From Fitchville Pond Inlet (Haughton Road Crossing, North Side Of Route 2, Exit 23), Bozrah, Us To Headwaters At Confluence Of Sherman Brook And Deep River, Lebanon. Waterbody Map River 5.9 Miles Good  

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Causes of Impairment for Reporting Year 2010

Connecticut, Thames

Description of this table
NOTE: Click on the underlined "Cause of Impairment" value to see a listing of those waters with that cause of impairment.
Cause of Impairment Size of Assessed Waters with Listed Causes of Impairment
Rivers and
Streams (Miles)		 Lakes, Reservoirs,
and Ponds (Acres)		 Bays and
Estuaries
(Square Miles)
Enterococcus Bacteria 4.8   4.9
Chlorophyll-A   112.4  
Dissolved Oxygen Saturation     13.4
Other Flow Regime Alterations 2.2    
Cause Unknown 5.6   2.6
Excess Algal Growth   112.4  
Fecal Coliform     17.1
Lead 2.1    
Nutrient/Eutrophication Biological Indicators   112.4 2.9
Dissolved Oxygen     13.4
Estuarine Bioassessments     14.6
Escherichia Coli (E. Coli) 7.9 14.3  
Mercury   29.6  

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Probable Sources Contributing to Impairments for Reporting Year 2010

Connecticut, Thames Watershed

Description of this table
Probable Source Size of Assessed Waters with Probable Sources of Impairments
Rivers and
Streams (Miles)		 Lakes, Reservoirs,
and Ponds (Acres)		 Bays and
Estuaries
(Square Miles)
Agriculture .6   1.6
Animal Feeding Operations (Nps) .6    
Atmospheric Deposition - Nitrogen     1.6
Baseflow Depletion From Groundwater Withdrawals 1.4    
Combined Sewer Overflows     1.6
Contaminated Sediments   29.6  
Flow Alterations From Water Diversions 1.5   1.3
Impacts From Hydrostructure Flow Regulation/Modification .7    
Industrial Point Source Discharge     3.3
Marina/Boating Sanitary On-Vessel Discharges     14.9
Municipal Point Source Discharges     13.3
Non-Point Source 2.1   8.4
On-Site Treatment Systems (Septic Systems And Similar Decentralized Systems)   112.4 8.5
Other Spill Related Impacts   29.6  
Residential Districts     22.7
Sanitary Sewer Overflows (Collection System Failures)     3.3
Source Unknown 13.4 112.4 3.2
Unspecified Urban Stormwater 3.5   22.4
Upstream Impoundments (E.G., Pl-566 Nrcs Structures) .8   .1
Waterfowl .7 126.7 17.1

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TMDL Alternatives by Cause of Impairment for Reporting Year 2010


Connecticut, Thames Watershed


No TMDL Alternatives reported.

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Cumulative TMDLs by Pollutant

Connecticut, Thames Watershed

This chart includes TMDLs since October 1, 1995.

Description of this table
NOTE: Click on the underlined "Number of TMDLs Completed" value to see a listing of those approved TMDLs for the pollutant.
Pollutant Number of TMDLs Completed Number of Causes of
Impairment Addressed
Escherichia Coli (E. Coli) color.gif 5 5
Nitrogen, Total color.gif 1 1

Total: 6 TMDLs; 0 Causes of Impairment



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