USGS Water-Year Summary 2019
01376950 LAKE TAPPAN AT OLD TAPPAN, NJ
LOCATION - Lat 41°01'06", long 74°00'04" referenced to North American Datum of 1983, Old Tappan Borough, Bergen County, NJ, Hydrologic Unit 02030103, at dam on Hackensack River, 0.5 mi north of Old Tappan, and 3.0 mi upstream from gaging station Hackensack River at Rivervale, NJ (01377000).
DRAINAGE AREA - 49 mi².
- WDR NJ-88-1: Capacity, WDR NJ-99-1: 1998 (elevation, contents).
PERIOD OF RECORD - From October 1966 to October 2010, month-end elevation and contents were provided by United Water New Jersey. Continuous-record reservoir station, 2011 to current year.
GAGE - Water-stage recorder with telemetry. Datum of gage is NGVD of 1929.
COOPERATION - United Water New Jersey.
EXTREMES FOR PERIOD OF RECORD - Maximum contents, 4,120,000,000 gal, Aug 28, 2011, gage height 55.73 ft; minimum contents 1,240,000,000 gal, Jan 10, 2011, gage height 46.35 ft.