USGS Water-Year Summary 2024
01209700 NORWALK RIVER AT SOUTH WILTON, CT
LOCATION - Lat 41°09'49.56", long 73°25'10.36" referenced to North American Datum of 1983, Fairfield County, CT, Hydrologic Unit 01100006, on right bank at upstream side of bridge on Kent Rd. at South Wilton, 2.5 mi north of Norwalk.
DRAINAGE AREA - 30 mi².
REVISIONS HISTORY - WDR CT-80-1: 1968-70 (P), 1971-79 (M,P). WDR CT-06-1: 1978-1980, 1982, 1987, 1989 (P). WDR CT-08-1: 2007 (P).
SURFACE-WATER RECORDS
PERIOD OF RECORD - Discharge: September 1962 to current year; occasional low-flow measurements: water years 1961-1962.
GAGE - Water-stage recorder and crest-stage gage. Datum of gage is 114.59 ft. above North American Vertical Datum of 1988; 115.69 ft. above National Geodetic Vertical Datum of 1929. Satellite telemetry at station.
EXTREMES OUTSIDE PERIOD OF RECORD - Flood of October 1955 reached a stage of 13.5 ft, from floodmarks.
EXTREMES FOR PERIOD OF RECORD - Minimum discharge, 0.30 ft³/s, Sep. 24, 1964.
WATER-QUALITY RECORDS
PERIOD OF RECORD - Oct. 2002 to Aug. 2004.
PERIOD OF DAILY RECORD - Oct. 2002 to Aug. 2004.
SPECIFIC CONDUCTANCE: Oct. 2002 to Aug. 2004.
WATER TEMPERATURE: Oct. 2002 to Aug. 2004.
INSTRUMENTATION - Water-quality monitor Oct. 2002 to Aug. 2004.
EXTREMES FOR PERIOD OF DAILY RECORD - Specific Conductance.--Maximum, 588 uS Feb. 3, 2004; minimum 125 uS Jan. 2, 2003.
Water Temperature.--Maximum, 24.0°C Aug. 14, 2003; minimum 0.0°C on numerous days during winter period.