LOCATION.--Lat 42°23'50.0", long
74°27'02.0" referenced to North American Datum of
1983, Schoharie County, NY, Hydrologic Unit 02020005, on left
bank at downstream side of bridge on State Route 990V, 0.2 mi
west of village of Gilboa, 0.5 mi downstream from dam on
Schoharie Reservoir, and 0.8 mi upstream from the Platter
Kill.
DRAINAGE AREA.--316 mi².
PERIOD OF RECORD.--October 1975 to current year (since
October 1983, discharges only for days of Schoharie Reservoir
spill and since October 1989, discharges only for days of mean
flow exceeding 10 ft³/s).
REVISIONS HISTORY.--WDR NY-90-1: Drainage area.
GAGE.--Water-stage recorder and crest-stage gage. Datum
of gage is 939.56 ft above NGVD of 1929 and 938.97 ft above
NAVD of 1988. Prior to Aug. 29, 2011, at site 200 ft upstream
at same datum.
REMARKS.--Entire flow, runoff from 315 mi², except for
periods of spill, diverted from Schoharie Reservoir through
Shandaken Tunnel into Esopus Creek upstream from Ashokan
Reservoir for water supply of City of New York.
Water Years 2014-23: Records fair.
EXTREMES FOR PERIOD OF RECORD.--Maximum discharge,
111,000 ft³/s, Aug. 28, 2011, gage height, 40.52 ft, from
floodmark at site then in use, 32.34 ft, from floodmark at
present site, from rating curve extended above 22,000 ft³/s on
basis of flow-over-dam measurement of peak flow; minimum daily
discharge, 0.04 ft³/s on many days, June to October 1976, and
Sept. 11-13, 1980, but may have been lower since October 1983
(see PERIOD OF RECORD); minimum instantaneous discharge not
determined.
EXTREMES OUTSIDE PERIOD OF RECORD.--Maximum discharge,
about 65,000 ft³/s, Oct. 16, 1955, by computation of flow over
dam; flood of Mar. 18, 1936, reached a discharge of 32,000
ft³/s, from information furnished by Bureau of Water Resources
Development, City of New York.