LOCATION--Lat 42°39’35", long 70°53’39", Essex County, Hydrologic Unit 01090001, on left bank 200 ft downstream from Willowdale Dam, 1.5 mi downstream from Howlett Brook, and 4 mi upstream from Ipswich.
DRAINAGE AREA--125 mi².
PERIOD OF RECORD--Discharge: June 1930 to current year.
Water-quality records: Water years 1954, 1976–79.
REVISED RECORDS--WSP 1621: 1930–58 (monthly runoff). WDR MA-RI-84-1: drainage area.
GAGE--Data Collection Platform with satellite telemeter. Datum of gage is 19.83 ft above NAVD 1988. Datum previously reported as 20.63 ft above NGVD 1929.
REMARKS--Diversions upstream for municipal supply of Reading, Lynn, Peabody, Danvers, Salem, and Beverly. Occasional regulation by dams and reservoirs upstream.
COOPERATION BY--Massachusetts Department of Conservation and Recreation, Office of Water Resources.