LOCATION.-- Lat 41°46'50", long 90°15'07" (NAD of 1927), in NW1/4 sec.34, T.81 N., R.6 E., Clinton County, Hydrologic Unit 07080101, on right bank at end of Eighth Avenue in Camanche, 5.0 mi upstream from Wapsipinicon River, 6.4 mi downstream from Clinton, 10.6 mi downstream from Lock and Dam 13, and at mile 511.8 upstream from Ohio River.

DRAINAGE AREA.-- 85,600 mi², approximately, at Fulton-Lyons Bridge at Clinton.

PERIOD OF RECORD.--

SURFACE-WATER DISCHARGE AND STAGE

DISCHARGE: June to August 1873 (fragmentary), October 1873 to current year. October 1932 to September 1939, published as "at Le Claire." June 1873 to December 1932, published in the Iowa State Planning Board report "Stream-flow records of Iowa, 1873-1932."

SURFACE-WATER QUALITY

CHEMICAL: October 1974 to September 1987, October 1994 to current year.

SEDIMENT: October 1994 to September 30, 1997 (discontinued).

SPECIFIC CONDUCTANCE: July 1975 to September 1976; sporadic measurements February 1977 to September 1981; October 1994 to September 30, 1997 (discontinued).

WATER TEMPERATURE: July 1975 to April 1989; January 1995 to September 30, 1997 (discontinued).

MISCELLANEOUS: Periodic observations.

REVISED RECORDS.-- WDR IA-75-1: 1974.

GAGE.-- Water-stage recorder and U.S. Army Corps of Engineers satellite telemeter. Datum of gage is 562.68 ft above NGVD of 1929 (562.62 ft NAVD 1988). June 6, 1969 to Sept. 16, 1988, water-stage recorder at site 400 ft. upstream at same datum. Auxiliary water-stage recorder at Lock and Dam 13 since Oct. 1, 1958. See WSP 1728 for history of changes prior to Oct. 1, 1955.

REMARKS.-- Minor flow regulation caused by navigation dams.

EXTREMES FOR PERIOD OF RECORD.--

SURFACE-WATER DISCHARGE AND STAGE: Maximum daily discharge, 307,000 ft³/s, discharge affected by regulation or diversion, April 28, 1965, gage height, 24.65 ft; minimum daily discharge, 6,500 ft³/s, December 25, 1933.

SUSPENDED-SEDIMENT CONCENTRATIONS: Maximum daily mean, 294 mg/L; Apr. 7, 1997; minimum daily mean, 1 mg/L several days in December 1995 - January 1996.

SUSPENDED-SEDIMENT LOADS: Maximum daily, 108,000 tons, Apr. 7, 1997; minimum daily, 96 tons, Jan. 9, 1996.

SPECIFIC CONDUCTANCE: Maximum daily 560 microsiemens Nov. 24 to Dec. 3, 1979; minimum daily 220 microsiemens Apr . 19, 20, 1976, Nov. 8-18, 1980.

WATER TEMPERATURE: Maximum daily 31.5°C July 21-23, 1983; minimum daily 0.0°C on many days during winter periods.

EXTREMES OUTSIDE PERIOD OF RECORD.--

SURFACE-WATER DISCHARGE AND STAGE: Maximum stage known since at least 1828, that of Apr. 28, 1965.