LOCATION.--Lat 42°18'30", long
74°23'24" referenced to North American Datum of 1983,
Greene County, NY, Hydrologic Unit 02020005, on right bank 200
ft southwest of State Highway 23 at Red Falls, 1.9 mi upstream
from mouth, and 2.2 mi southeast of Prattsville.
DRAINAGE AREA.--68.6 mi².
PERIOD OF RECORD.--October 1997 to current year.
GAGE.--Water-stage recorder and crest-stage gage. Datum
of gage is 1,268.54 ft above NAVD of 1988.
REMARKS.--Flow regulated to some extent at high flows by
three flood-retardation reservoirs, combined drainage area of
19.2 mi². Seasonal diversion for snowmaking by Ski Windam ski
area at Windham.
Water Years 2014-23: Records fair except those for estimated
daily discharges, which are poor.
EXTREMES FOR PERIOD OF RECORD.--Maximum discharge,
44,200 ft³/s, Aug. 28, 2011, gage height, about 20.0 ft,
outside gage height was about 21.4 ft, from floodmarks, from
rating curve extended above 2,900 ft³/s on basis of
step-backwater analyses at gage heights about 11.4 ft and about
20.0 ft; minimum discharge, 0.08 ft³/s, Aug. 22, 2022, gage
height, 1.05 ft; minimum gage height, 0.97 ft, Aug. 9,
2012.
EXTREMES OUTSIDE PERIOD OF RECORD.--Flood of Jan. 19,
1996, reached a stage of about 11.4 ft, from floodmark,
discharge, 16,400 ft³/s, on basis of step-backwater analysis of
peak flow.