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Available data

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Continuous data

17 data types available - data from 2007-10-01 to 2026-08-05

Daily data

7 data types available - data from 2001-10-01 to 2026-08-04

Field measurements

1 data types available - data from 2000-05-02 to 2026-06-23

Discrete sample data

63 Observed properties (data types) available - with data from 2019-06-26 to 2026-07-23

291 Sampling activities

Peak measurements

1 data types available - with data from 2008-12-12 to 2011-08-28

Statistical tables for select daily data types

7 data types available - data from 2003-10-01 to 2026-08-03

Important information about this monitoring location

The elevation of this gage is -1.01 ft above NAVD of 1988. To obtain stream water surface elevation values in NAVD88, add -1.01 feet to gage height values.

Location details and information

Available location images

Connecticut River at Old Lyme

Connecticut River at Old Lyme, CT

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Operated in cooperation with:

Connecticut Department of Energy and Environmental Protection

Metadata Element	Location Metadata	Metadata Code
Agency	U.S. Geological Survey	USGS
Location identification number	01194796	n/a
Location name	CONNECTICUT RIVER AT OLD LYME, CT	n/a
Site type	Estuary	ES
Decimal latitude (WGS84)	41.31248746834132	n/a
Decimal longitude (WGS84)	-72.34590046637659	n/a
Latitude-longitude method	Interpolated from MAP.	M
Latitude-longitude accuracy	Accurate to + or - 1 sec.	S
District	Connecticut	09
State	Connecticut	09
County	Lower Connecticut River Valley Planning Region	130
Country	United States of America	n/a
Altitude of gage/land surface	-1.01 feet	n/a
Method altitude determined	Level or other surveyed method.	L
Altitude accuracy	0.01 feet	n/a
Altitude datum	North American Vertical Datum of 1988	NAVD88
Subbasin hydrologic unit	Outlet Connecticut River	01080205
Drainage basin		n/a
Date of first construction		n/a
Drainage area	11224 square miles	n/a
Contributing drainage area		n/a
Time zone abbreviation	EST	n/a
Site honors Daylight Saving Time	Y	n/a
National aquifer		n/a
Local aquifer		n/a
Local aquifer type		n/a
Well depth		n/a
Hole depth		n/a
Source of depth data		n/a

Monitoring location Connecticut River at Old Lyme, CT - USGS-01194796