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USGS 01398102 South Branch Raritan River at South Branch NJ


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LOCATION.--Lat 40°32'49", long 74°41'47" referenced to North American Datum of 1983, Branchburg Township, Somerset County, NJ, Hydrologic Unit 02030105, on right upstream wingwall of bridge on Studdiford Drive (South Branch Road) at village of South Branch, 0.8 mi upstream from confluence with North Branch Raritan River, and 2.7 mi southeast of Readington.
DRAINAGE AREA.--265 mi2.
PERIOD OF RECORD.--Continuous-record gage-height station 1998 to current year. Miscellaneous measurements, water years 1976-83, 1998 to current year.
GAGE.--Water-stage recorder with telemetry and crest-stage gage. Datum of gage is 45.54 ft above NGVD of 1929.
REMARKS.--Flow regulated by Spruce Run (see 01396790) and Round Valley Reservoirs. Peak stages at this gage maybe affected by backwater from the North Branch Raritan River. 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, 20.29 ft, Sep 16, 1999.


PERIOD OF RECORD.--Water years 1976-83, 1998 to current year.
REMARKS.--Discrete water-quality data were collected as part of the New Jersey Ambient Surface-Water-Quality Monitoring Network.

Peak Flood Chart

Gage Photo

This station managed by the New Jersey Water Science Center.

Available Parameters Available Period
2009-04-22  2022-09-26


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Summary of all available data for this site
Instantaneous-data availability statement

Gage height, feet

Most recent instantaneous value: 2.63 09-26-2022   14:15 EDT
Graph of  Gage height, feet

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