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 analysis.

 

SURFACE-WATER RECORDS
LOCATION.--Lat 40°30'10", long 74°35'15" referenced to North American Datum of 1983, Millstone Borough, Somerset County, NJ, Hydrologic Unit 02030105, on left bank at downstream side of bridge on County Route 514 (Amwell Road), in Millstone Borough, 2.7 mi south of Manville, and 4.4 mi upstream from mouth.
DRAINAGE AREA.--264 mi².
PERIOD OF RECORD.--Continuous-record gaging station, water years 1903-04. Annual maximum, water years 1999 to current year.
GAGE.--Water-stage recorder with telemetry and crest-stage gage. Datum of gage is 24.4 ft above NGVD of 1929.
REMARKS.--Diurnal fluctuations in gage height possibly due to flow pattern in sewage effluent that enter the river upstream of gage. 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 gage height, 22.34 ft, Aug 28, 2011.

Peak Flood Chart

National Weather Service flood stage for this gage is 10 ft.