LOCATION.-- Lat 38°03'40", long 88°09'35" (NAD of 1927), in NW1/4SE1/4 sec.25, T.5 S., R.9 E., White County, Hydrologic Unit 05120114, on right bank at downstream side of Possum Bridge, 2.3 mi south of Main Street Bridge in Carmi, 7.8 mi downstream from Skillet Fork, and at mile 30.5.

DRAINAGE AREA.-- 3,102 mi².

PERIOD OF RECORD.--

SURFACE-WATER DISCHARGE AND STAGE

DISCHARGE: October 1939 to current year.

STAGE: October 1908 to December 1912. Water years 1994 to current year.

SURFACE-WATER QUALITY

CHEMICAL: Water years 1978-79.

SPECIFIC CONDUCTANCE: Water years 1978-79.

WATER TEMPERATURE: Water years 1978-79.

BIOLOGICAL: Algae, water years 1978-79.

REVISED RECORDS.-- WDR IL-75-1: Drainage area.

GAGE.-- Water-stage recorder, U.S. Army Corps of Engineers satellite telemeter. Datum of gage is 339.91 ft above NGVD of 1929. Prior to December 1912, nonrecording gage at site 3.1 mi upstream at datum 0.4 ft higher. Oct. 1 to Nov. 9, 1939, nonrecording gage at present site and datum. Since Nov. 14, 1939, auxiliary water-stage recorder 3.1 mi upstream.

REMARKS.-- At extremely high stages, there is diversion 6 mi above the gage through McHenry Slough to the Wabash River.

EXTREMES FOR PERIOD OF RECORD.--

SURFACE-WATER DISCHARGE AND STAGE: Maximum discharge, 46,900 ft³/s, May 12, 1961, gage height 36.66 ft; maximum gage height, 36.70 ft, May 13, 1961, discharge unknown; no flow, Sept. 15-17, 1952, result of temporary dam upstream; minimum unregulated discharge, 0.6 ft³/s, Sept. 9, 1953, July 31, 1954.