USGS Water-Year Summary 2023
05442300 ROCK RIVER AT DIXON, IL
LOCATION - Lat 41°50'39", long 89°29'09" referenced to North American Datum of 1983, in NW 1/4 NW 1/4 NE 1/4 sec.5, T.21 N., R.9 E., Lee County, IL, Hydrologic Unit 07090005, on left downstream side of Peoria Avenue bridge, 0.2 mi. downstream from Route 26, about 1/4 mi. downstream from Dixon hydro-electric dam, 4.2 mi. downstream from Seven Mile Branch River, and at mile 87.0.
DRAINAGE AREA - 8,615 mi².
REVISIONS HISTORY - Revisions: Gage datum was updated to 628.51 ft NAVD88 on Sept. 15, 2022, based on a GNSS Level II survey using GEOID18.
SURFACE-WATER RECORDS
PERIOD OF RECORD -
SURFACE-WATER DISCHARGE AND STAGE
DISCHARGE: May 2010 to current.
STAGE: Water years 2010 to current.
PARTIAL RECORD: Miscellaneous discharge measurement, water year 2007.
PRECIPITATION: May 2010 to current.
GAGE - Water-stage recorder, satellite telemeter, crest-stage gage, and unheated rain gage. Datum of gage is 628.51 ft. above NAVD of 1988.
EXTREMES OUTSIDE PERIOD OF RECORD - Flood of April 20 or 21 1973 reached a stage of 20.45 ft, site 1000 ft. upstream at current datum, from Army Corp of Engineers Flood Profile, discharge not determined.
EXTREMES FOR PERIOD OF RECORD - SURFACE-WATER DISCHARGE AND STAGE DISCHARGE: Maximum discharge, 42,100 ft³/s, July 25, 2010; gage height, 17.83 ft; maximum gage height, 18.40 ft., Feb. 24, 2019, due to ice jam; minimum discharge, 669 ft³/s, June 30, 2012; gage height, 7.20 ft, due to regulation.
PRECIPITATION: Maximum daily total, 4.32 in., Aug. 18, 2016.