During winter months, cold and ice may
result in inaccurate real-time lake or reservoir elevation data.
Adjustments or deletions of this data can only be done after detailed
Funding for this site is provided by:
Lat 40°19'09", long 74°06'54"
referenced to North American Datum of 1983, Colts Neck Township,
Monmouth County, NJ, Hydrologic Unit 02030104, at dam on Swimming
River, 3.3 mi southwest of Red Bank, and 4.8 mi upstream from
PERIOD OF RECORD.--
Continuous-record reservoir station, August
1922 to current year. Unpublished reservoir station records, August
1922 to September 1999, available from the USGS New Jersey Water
Science Center. Records from October 1999 to September 2005 published
WDR NJ-00-1: 1999 (elevation, contents).
Water-stage recorder with telemetry above concrete dam.
Datum of gage is National Geodetic Vertical Datum 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
Reservoir formed by concrete core and earth embankment
dam with a Trenton-type overflow spillway. Capacity at spillway level,
2,610,000,000 gal, elevation, 35.0 ft. Reservoir used for storage and
water diversion by New Jersey-American Water Company. Reservoir
enlarged and dam raised in 1962. Outflow is controlled by gates on a
pipe. Annual extremes beginning in water year 2014 can be obtained by
using this link
. Prior to water
year 2014, annual extremes can be obtained on the respective annual
water year summary
EXTREMES FOR PERIOD OF RECORD.--
Maximum contents, 3,240,000,000
gal, Aug 28, 2011, elevation 37.92 ft. Minimum contents and elevation