USGS Water-Year Summary 2020
07257500 ILLINOIS BAYOU NEAR SCOTTSVILLE, AR
LOCATION - Lat 35°27'59", long 93°02'28" referenced to North American Datum of 1983, in SE 1/4 SW 1/4 sec.31, T.10 N., R.19 W., Pope County, AR, Hydrologic Unit 11110202, on downstream side of bridge on State Hwy 164, 1.3 mi north of Scottsville, and 3.1 mi downstream from North Fork Illinois Bayou.
DRAINAGE AREA - 241 mi².
PERIOD OF RECORD - Oct 1947 to Sep 1970 and Oct 1999 to current year. Annual maximum water years 1971 to 1999.
GAGE - Water-stage recorder. Datum of gage is 447.54 ft above NGVD of 1929. Prior to Mar 1948, nonrecording gage at same site and datum.
EXTREMES OUTSIDE PERIOD OF RECORD - Flood of May 10, 1943, reached a stage of 24.6 ft, from floodmark set by local residents (discharge, 77,000 ft³/s).
EXTREMES FOR PERIOD OF RECORD - Maximum discharge 130,000 ft³/s Dec 3, 1982, from rating curve extended above 56,100 ft³/s on basis of contracted-opening and flow-over-road measurement of peak flow and occurred during period of computation of annual maximum only, water years 1971 to 1999.