LOCATION.-- Lat 40°55'45", long 89°27'42" (NAD of 1927), in NW1/4 sec.22, T.11 N., R.9 W., Peoria County, Hydrologic Unit 07130001, at center of Atchison, Topeka and Sante Fe Railroad bridge, 1 mi north of Chillicothe and at mile 181.9.

DRAINAGE AREA.-- Not determined.

PERIOD OF RECORD.--

SURFACE-WATER QUALITY

SEDIMENT: May 1993 to November 1993, water years 1994 to 2000 (March to December), March 2001 to current year.

MISCELLANEOUS: Sediment concentration and particle size, water years 1996-99, 2002-03.

REMARKS.-- Water discharge used to compute sediment record are from Illinois River at Henry (station 05558300). Suspended-sediment samples were collected by a local observer twice weekly with additional samples colleced during high runoff periods. Samples were not collected (and data are not published) during periods of ice.

EXTREMES FOR PERIOD OF RECORD.--

SUSPENDED-SEDIMENT CONCENTRATIONS: Maximum daily, 554 mg/L, Aug. 29, 2004; minimum daily, 16 mg/L, Mar. 7, 1998 and Dec. 24, 2003.

SUSPENDED-SEDIMENT LOADS: Maximum daily, 93,800 tons, July 20, 1996; minimum daily, 140 tons, Oct. 30, 2002.