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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.

USGS 01405400 Manalapan Brook at Spotswood NJ


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Estimated flood stage is 19 feet.

When heavy rain is forecast, gates in the dam are often opened to prevent flooding. This results in a sharp reduction of lake levels before a storm, and rises in lake levels after the storm. USGS records are corrected for this gate flow before publication.

gage photoLOCATION. --Lat 40°23'22", long 74°23'26" referenced to North American Datum of 1983, Spotswood Borough, Middlesex County, NJ, Hydrologic Unit 02030105, on right bank upstream of DeVoe Lake Dam in Spotswood, 0.1 mi upstream from Cedar Brook, and 0.6 mi upstream from confluence with Matchaponix Brook.
DRAINAGE AREA. --40.7 mi2.
PERIOD OF RECORD. --January 1957 to current year.
GAGE. --Water-stage recorder above concrete dam. Datum of gage is NGVD of 1929 (levels by Duhernal Water System). January 1957 to September 1966 at datum 17.72 ft higher. Flow through gates in the dam not included in real-time data, but are included in historic flow data. Gates are sometimes opened when heavy rains are expected.
COOPERATION. --Funding for this gage is provided by the New Jersey Department of Environmental Protection, and the U.S. Geological Survey.

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This station managed by the New Jersey Water Science Center.

Available Parameters Available Period
All 2 Available Parameters for this site
00060 Discharge 2007-10-01  2016-09-28
00065 Gage height 2007-10-01  2016-09-28

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Discharge, cubic feet per second

Most recent instantaneous value: 10   09-28-2016   13:15 EDT
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Daily discharge, cubic feet per second -- statistics for Sep 28 based on 58 years of record more
Most Recent
Value Sep 28
Median 75th
Mean Max
0.20 10 19 28 44 48 345

Gage height, feet

Most recent instantaneous value: 17.87   09-28-2016   13:15 EDT
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