USGS Water-Year Summary 2022
05443000 ROCK RIVER ABOVE SINNISSIPPI DAM AT ROCK FALLS, IL
LOCATION - Lat 41°47'15", long 89°40'35" referenced to North American Datum of 1983, in SE 1/4 SW 1/4 SE 1/4 sec.22, T.21 N., R.7 E., Whiteside County, IL, Hydrologic Unit 07090005, on concrete wall at mouth of Hennepin Feeder Canal, 300 ft upstream of the Upper Rock Falls Dam, and at mile 73.6.
DRAINAGE AREA - 8,740 mi².
PERIOD OF RECORD -
SURFACE-WATER DISCHARGE AND STAGE
STAGE: October 2003 to current.
GAGE - Water-stage recorder and cell radio telemeter. Datum of Gage is 630.00 ft above NGVD of 1929, based on elevation provided by Illinois Department of Natural Resources (629.80 ft NAVD 1988).
EXTREMES FOR PERIOD OF RECORD - Maximum gage height, 7.85 ft, October 24, 2008; minimum 0.75 ft, observed, due to dam repair September 28 - October 1, 2010, as provided by Illinois Department of Natural Resources.