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 41°02'42", long 74°17'43"
referenced to North American Datum of 1983, Wanaque Borough, Passaic
County, NJ, Hydrologic Unit 02030103, at Raymond Dam on Wanaque River
at Wanaque, 1,700 ft upstream of bridge on County Route 511 (Ringwood
Avenue), and 3.3 mi north of Riverdale.
PERIOD OF RECORD.--
February 1928 to current year.
WDR NJ-85-1: 1984 (M). WRD US-2013: Usable
Water-stage recorder with telemetry. Datum of gage is
National Geodetic Vertical Datum of 1929 (levels by North Jersey
District Water Supply Commission).
Reservoir is formed by earthfill with concrete-core
wall main dam and seven secondary dams; dams completed in 1927 and
storage began in March 1928. Total capacity at spillway level,
29,630,000,000 gal, elevation, 302.4 ft, prior to 1986, 300.3 ft.
Available capacity at spillway level, 29,488,000,000 gal (revised).
Outflow mostly controlled by sluice gates in intake conduits in
gatehouse. Water is diverted from reservoir for municipal supply.
Diversion to reservoir from Posts Brook, Pompton River, and Ramapo
River. Records given herein represent total capacity. 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, 31,280,000,000
gal, Apr 5, 1984, elevation, 304.52 ft; minimum contents, 5,110,000,000
gal, Dec 26, 1964, elevation, 256.06 ft.
Occasionally the reservoir levels appear to be
several tenths of a foot too low due to possible drawdown caused by use
of water supply intakes at certain levels.