LOCATION.-- Lat 38°42'19", long 87°31'14" (NAD of 1927), T.3 N., R.10 W., Lawrence County, IL, Hydrologic Unit 05120111, (VINCENNES, IL-IN. quadrangle), on right bank 30 ft east of Illinois State Highway 33, 300 ft upstream from Kelso Creek, 570 ft downstream from U.S. Highway 50 bridge, 5.1 mi downstream from Maria Creek, 7.5 mi upstream from Embarras River and at mile 129.6.

DRAINAGE AREA.-- 13,706 mi².

PERIOD OF RECORD.--

SURFACE-WATER DISCHARGE AND STAGE

DISCHARGE: October 1929 to September 1994. Prior to December 1929, monthly discharge only published in WSP 1305.

STAGE: October 1994 to current year. Gage-height records collected at site 1.8 mi downstream are available for flood peaks in 1867 and 1883, intermittent records 1887-1904, and continuous since November 1904, in reports of National Weather Service.

REVISED RECORDS.-- WSP 1173: 1943 (maximum gage height only). WSP 1335: 1930-31, 1933, 1936. WSP 1909: l955. WDR IN-73-1: Drainage area.

GAGE.-- Water-stage recorder. Datum of gage is 394.43 ft above NGVD of 1929 (394.01 ft NAVD 1988). Oct. 1, 1968, to June 19, 1979, recording gage at site 570 ft upstream at same datum. Oct. l, l960, to September 30, 1968, nonrecording gage at site 1.8 mi downstream at same datum. Oct. 1, 1960, to Sept. 30, 1968, auxiliary water stage recorder at site 2.8 mi upstream from base gage at datum 0.80 ft lower. See WSP 1725 for history of changes prior to Oct. 1, 1960.

REMARKS.-- Flow partially regulated by upstream reservoirs.

EXTREMES FOR PERIOD OF RECORD.--

SURFACE-WATER DISCHARGE AND STAGE: Maximum gage height, 29.33 ft, May 22, 1943; minimum gage height unknown prior to 1988, since 1988, minimum gage height, 3.92 ft, Sept. 4, 1988.

EXTREMES OUTSIDE PERIOD OF RECORD.--

SURFACE-WATER DISCHARGE AND STAGE: Flood of Mar. 29, 1913, reached a stage of 26.3 ft, at former site 1.8 mi downstream and at present datum, from floodmarks, determined by U.S. Army Corps of Engineers, discharge, 255,000 ft³/s.