LOCATION.-- Lat 41°47'14", long 89°40'35" (NAD of 1927), in SW1/4SE1/4 sec.22, T.21 N., R.7 E., Whiteside County, Hydrologic Unit 07093005, 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.(revised WRD IL-75-1). | |
PERIOD OF RECORD.-- | |
SURFACE-WATER DISCHARGE AND STAGE | |
STAGE: October 2003 to current year. | |
GAGE.-- Water-stage recorder and phone telemeter. Datum of Gage is 630.00 ft above NGVD 1929, based on elevation provided by Illinois Department of Natural Resources. | |
EXTREMES FOR PERIOD OF RECORD.-- | |
STAGE: Maximum gage height, 6.88 ft, Dec. 22, 2003; minimum 5.45 ft, Jan. 8, 2004. | |