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Important for you to know:

  • New to WDFN: see current water conditions throughout the state using the new State Pages. Filter by continuous data type and age of data, view latest values, and link to graphing options to explore the data further. To learn more, read our announcement on the Water Data for the Nation blog.

Hydrological Unit: Long Island Sound

HUC Name
0203020300 Long Island Sound
Monitoring Locations
Site number Name Site type
01127768 THAMES R AT GROTON, CT. Estuary
01208837 HOUSATONIC RIVER NR NELLS ISLAND NR STRATFORD, CT Estuary
01208839 HOUSATONIC RIVER NEAR MILFORD POINT AT DEVON, CT Estuary
01297000 LONG ISLAND SOUND AT RYE NY Estuary
405130073461601 B 4. 1 Test hole not completed as a well
410502073236000 NORWALK HARBOR AT THE COVE MARINA NR E NORWALK, CT Estuary
410613073215801 SAUGATUCK RIVER LOWER EMBAYMENT NEAR SAUGATUCK, CT Estuary
410635072245901 S 36921. 1 Well
410729073171701 MILL RIVER AT SOUTHPORT HARBOR NEAR SOUTHPORT, CT Estuary
410757073165601 MILL RIVER AT PEQUOT YACHT CLUB AT SOUTHPORT, CT Estuary
411017073103001 POQUONNOCK RIVER Stream
411043073072801 HOUSATONIC RIVER dup 1 Stream
411513072512301 FARM RIVER AT FARM RIVER MARINA NR EAST HAVEN, CT Estuary
411532072510801 FARM RIVER AT ROUTE 142 BRIDGE NEAR EAST HAVEN, CT Estuary
411547072483901 BRANFORD RIVER Stream
411610072544701 LONG ISLAND SOUND dup 1 Stream
411653072543901 NEW HAVEN HARBOR Stream
411838071513000 WATCH HILL COVE TIDE GAGE WESTERLY, RI Coastal
411940071590300 MYSTIC RIVER AT RAM ISLAND YACHT CLUB AT NOANK, CT Estuary
412030072051001 THAMES RIVER dup 2 Stream
412038071574900 MYSTIC HARBOR NR MYSTIC POINT MARINA NR MYSTIC, CT Estuary
412047071580800 MYSTIC HARBOR AT SAFE HARBOR MARINA NR MYSTIC, CT Estuary
412115072050701 THAMES RIVER dup 3 Stream