LOCATION.-- Lat 39°39'33", long 88°03'48" (NAD of 1927), in NW1/4SW1/4 sec.14, T.14 N., R.10 E., Coles County, Hydrologic Unit 05120112, on right bank at downstream side of bridge on State Highway 133, 1.5 mi west of Oakland, 13 mi east of Arcola, and at mile 143.6.

DRAINAGE AREA.-- 542 mi².

PERIOD OF RECORD.--

SURFACE-WATER DISCHARGE AND STAGE

DISCHARGE: October 1978 to September 1982.

SURFACE-WATER QUALITY

SEDIMENT: January 1979 to September 1982.

GAGE.-- Water-stage recorder. Datum of gage is 591.33 ft above NGVD of 1929.

EXTREMES FOR PERIOD OF RECORD.--

SURFACE-WATER DISCHARGE AND STAGE: Maximum discharge, 12,000 ft³/s Mar. 5, 1979, gage height, 23.78 ft; minimum daily, 8.0 ft³/s Oct. 10-14, 1980.

SUSPENDED SEDIMENT CONCENTRATIONS: Maximum daily mean, 2,340 mg/L Apr. 11, 1979; minimum daily mean, 1 mg/L Nov. 8, 11-16, 1979, Jan. 14, Nov. 29, 30, 1980.

SUSPENDED SEDIMENT LOADS: Maximum daily, 37,600 tons Apr. 13, 1979; minimum daily, 0.03 ton Nov. 8, 1979.