LOCATION.--Lat 43°01'37.3", long 91°10'21" referenced to North American Datum of 1927, in SE 1/4 NE 1/4 SE 1/4 sec.22, T.95 N., R.3 W., Clayton County, IA, Hydrologic Unit 07060001, on right bank in city park at east end of Main Street in McGregor, 2.6 mi upstream from Wisconsin River, 4.3 mi downstream from Yellow River, and 633.4 mi upstream from Ohio River. (map)

DRAINAGE AREA.--67,500 mi².

SURFACE-WATER RECORDS

PERIOD OF RECORD.--Discharge records from August 1936 to September 2005, October 2007 to current year; stage-only records from October 2005 to September 2007.

REVISED RECORDS.--WDR IA-75-1: 1974. WDR-US-2009: 2002.

GAGE.--Water-stage recorder. Datum of gage is 604.84 ft above National Geodetic Vertical Datum of 1929. Auxiliary gage at Lock and Dam 9 (station 05388410), 14.1 mi upstream, at datum 5.30 ft lower. Prior to June 1, 1937, and since June 2, 1939, auxiliary water-stage recorder; June 1, 1937, to June 1, 1939, non-recording auxiliary gage.

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

WATER-QUALITY RECORDS

PERIOD OF RECORD.--Water years 1975-2004.

PERIOD OF DAILY RECORD.--
SPECIFIC CONDUCTANCE: Daily instantaneous values collected in conjunction with suspended-sediment samples, July 1975 to September 2004, records fragmentary.
WATER TEMPERATURES: Daily instantaneous values collected in conjunction with suspended-sediment samples, July 1975 to September 2004, records fragmentary.
SUSPENDED-SEDIMENT CONCENTRATION AND DISCHARGE: July 1975 to September 2004.

Advanced Hydrologic Prediction Service

U.S. Army Corps of Engineers - Saint Paul District