SURFACE-WATER RECORDS
LOCATION.--Lat 40°36'07", long 74°27'27" referenced to North American Datum of 1983, Green Brook Township, Somerset County, NJ, Hydrologic Unit 02030105, on downstream left wingwall of bridge on Rock Avenue in Plainfield, 0.3 mi north of West Front Street, and 0.6 mi south of U.S. Route 22.
DRAINAGE AREA.--18.2 mi².
PERIOD OF RECORD.--Annual maximum gage, water years 1972-79, 1992-2007. Continuous-record gage-height station with annual maximum discharge, 2008 to current year. Miscellaneous measurements, water years 1972-74, 1979, 1992, 2000-02, 2005-06.
REVISIONS HISTORY.--Revisions prior to water year 2014 available from Water Data Reports (WDR) listed above in Revised Records. Revisions subsequent to Water Year 2014 can be obtained by using this link. 
GAGE.--Water-stage recorder with telemetry and crest-stage gage. Datum of gage is 43.85 ft above NGVD of 1929.
REMARKS.--Annual peak data can be obtained by selecting Peak streamflow from the 'Available data for this site' drop-down menu above or by using this link.
EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 10,400 ft³/s from rating curve extension on basis of contracted opening and flow-over-road computation at bridge on Madison Avenue 1.1 mi downstream, adjusted for change in drainage area, Aug 2, 1973, gage height, 13.6 ft, from high-water mark, adjusted to current datum.

Peak Flood Chart