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:
Lat 40°23'22", long 74°23'26"
referenced to North American Datum of 1983, Spotswood Borough,
Middlesex County, NJ, Hydrologic Unit 02030105, on right bank upstream
of DeVoe Lake Dam in Spotswood, 0.1 mi upstream from Cedar Brook, and
0.6 mi upstream from confluence with Matchaponix Brook.
PERIOD OF RECORD.--
January 1957 to current year.
WSP 1722:1957-60, WDR NJ-2005-1:1989(M),
Water-stage recorder with telemetry above concrete dam.
Datum of gage is NGVD of 1929 (levels by Duhernal Water System).
January 1957 to September 1966 at datum 17.72 ft higher.
Records fair, except for estimated discharges, which
are poor. Discharge given herein includes flow over dam and through
sluice gates when open. Some regulation by Lake Manalapan, Helmetta
Pond, and DeVoe Lake.
EXTREMES FOR PERIOD OF RECORD.--
Maximum discharge, 6,550
/s, estimated, includes estimated flow through sluice
gates, Aug 28, 2011, gage height, 22.22 ft, from high-water mark;
minimum discharge, 0.0 ft3
/s, many days, undetermined amount
of leakage through sluice gates when closed and lake level is below
When heavy rain is forecast, gates in the dam
are often opened to prevent flooding. This results in a sharp reduction
of lake levels before a storm, and rises in lake levels after the
storm. USGS records are corrected for this gate flow before