During winter months, cold and ice may
result in inaccurate real-time gage height and streamflow data.
Adjustments or deletions of this data can only be done after detailed
Funding for this site is provided by:
40°19'11", long 74°06'56" referenced to North
American Datum of 1983, Colts Neck Township, Monmouth County, NJ,
Hydrologic Unit 02030104, on left bank 50 ft upstream from spillway at
Swimming River Reservoir, 1,000 ft upstream of bridge on Swimming River
Road (County Route 50), 3.3 mi southwest of Red Bank, and 4.8 mi
upstream from mouth.
PERIOD OF RECORD.--
August 1922 to current year.
WSP 891: 1939. WDR NJ-83-1: Drainage area. WDR
Water-stage recorder with telemetry above concrete dam.
Datum of gage is 30.00 ft above NGVD of 1929. Prior to Jan 19, 1962, at
site 800 ft upstream at datum 17.67 ft lower. Jan 19 to Mar 30, 1962,
non-recording gage, 700 ft upstream at datum 13.87 ft lower.
Records fair, except for estimated discharges and
discharges less than 5 ft3
/s, which are poor. Records given
herein represent flow over spillway and flow or leakage through blowoff
gates. Flow regulated by diversions from Swimming River Reservoir for
municipal supply. Reservoir used for storage and water diversion by New
Jersey-American Water Company. Reservoir enlarged and dam raised in
1962. Discharges above 1,100 ft3
/s from rating curve
extension on basis of weir formula.
EXTREMES FOR PERIOD OF RECORD.--
Maximum discharge, 8,910
/s, from rating curve extended above 1,100
/s on basis of weir formula, Oct 27, 1943, gage height,
8.96 ft, site and datum then in use; minimum discharge, 0.00
/s, many days.
EXTREMES OUTSIDE PERIOD OF RECORD.--
Flood of July 1919 reached a
stage of 7.84 ft (site and datum then in use; from floodmark),
discharge, approximately 11,800 ft3
PERIOD OF RECORD1.--
Water years 1923-24, 1952,
1960-72, 1974-81, 2007.
1 Water-Quality Records