05587455 MISSISSIPPI RIVER BELOW GRAFTON, IL

LOCATION.--Lat 38°57'04", long 90°22'16", in sec.24, T.6 N., R.11 W., Jersey County, Hydrologic Unit 07110009, 11.3 mi above Lock and Dam 26, 19.0 mi above mouth of Missouri River, and at mile 214.6 upstream from the mouth of the Ohio River.

DRAINAGE AREA.--171,300 mi2, approximately.

PERIOD OF RECORD.--March 1989 to current year. National stream-quality accounting network station 1989 to 1994.

REMARKS.--Established ambient water-quality monitoring network station November 1992. Sediment records fair.

PERIOD OF DAILY RECORD.--
SUSPENDED-SEDIMENT: October 1989 to current year.

EXTREMES FOR PERIOD OF DAILY RECORD.--
SUSPENDED-SEDIMENT CONCENTRATIONS: Maximum daily mean, 1,910 mg/L, May 23, 1990; minimum daily mean, 1 mg/L, Sept. 10, 1991.
SUSPENDED-SEDIMENT LOADS: Maximum daily, 1,090,000 tons, May 23, 1990; minimum daily, 186 tons, Sept. 10, 1991.

EXTREMES FOR CURRENT YEAR.--
SUSPENDED-SEDIMENT CONCENTRATIONS: Maximum daily mean, 811 mg/L, Jan. 9; minimum daily mean, 41 mg/L, Nov. 8.
SUSPENDED-SEDIMENT LOADS: Maximum daily, 433,000 tons, Apr. 2; minimum daily, 5,150 tons, Nov. 15.