LOCATION.-- Lat 41°21'57", long 89°29'54" (NAD of 1927), in SW1/4SE1/4 sec.18, T.16 N., R.9 E., Bureau County, Hydrologic Unit 07130001, on right bank 500 ft downstream from bridge on U.S. Highways 6 and 34, 0.6 mi downstream from Epperson Run, 1.5 mi west of Princeton, and at mile 20.5.

DRAINAGE AREA.-- 196 mi².

PERIOD OF RECORD.--

SURFACE-WATER DISCHARGE AND STAGE

DISCHARGE: March 1936 to current year. Prior to October 1974, published as Bureau Creek at Princeton.

STAGE: Water years 1994 to current year.

SURFACE-WATER QUALITY

CHEMICAL: Water years 1978-91.

BIOLOGICAL

ALGAE: Water year 1997.

BENTHIC MACROINVERTEBRATES: Water year 1997.

REVISED RECORDS.-- WSP 1175: 1940-41, 1948. WSP 1308: 1942(M). WDR IL-75-1: Drainage area.

GAGE.-- Water-stage recorder and U.S. Army Corps of Engineers satellite telemeter. Datum of gage is 555.39 ft above NGVD of 1929 (levels by U.S. Army Corps of Engineers) (555.13 ft NAVD 1988). Prior to July 18, 1940, nonrecording gage at bridge 425 ft upstream at datum 30.00 ft lower. July 18, 1940, to Sept. 18, 1944, water-stage recorder at site 500 ft upstream at present datum.

EXTREMES FOR PERIOD OF RECORD.--

SURFACE-WATER DISCHARGE AND STAGE: Maximum discharge, 12,500 ft³/s, May 17, 1974, gage height, 16.01 ft; no flow during January 1940 and for several days in October and November 1953.