LOCATION.--Lat 40°49'18.7", long 92°53'27.8" referenced to North American Datum of 1927, in NW 1/4 SE 1/4 NW 1/4 sec.35, T.70 N., R.18 W., Appanoose County, IA, Hydrologic Unit 10280201, on left bank 600 ft downstream from outlet of Rathbun Dam, 1.7 mi north of Rathbun, 3.8 mi upstream from Walnut Creek, and 30.0 mi upstream from Iowa-Missouri state line. (map)

DRAINAGE AREA.--549 mi².

SURFACE-WATER RECORDS

PERIOD OF RECORD.--Discharge records from October 1956 to current year. Prior to March 1957, monthly mean discharge for some periods published in WSP 1730.

REVISED RECORDS.--WSP 1560: Drainage area. WDR-US-2009: 1996 (M).

GAGE.--Water-stage recorder. Datum of gage is 847.92 ft above National Geodetic Vertical Datum of 1929. Prior to November 16, 1960, non-recording gage, and November 17, 1960, to September 30, 1969, water-stage recorder, both at site 3.1 mi downstream at datum 4.65 ft lower.

REMARKS.--Flow regulated by Rathbun Lake (station 06903880) since November 21, 1969. Records of discharge include flow diverted from the reservoir to Rathbun Fish Hatchery ponds beginning July 21, 1975. Diverted flow returns to the stream 0.1 mi downstream from gage. Rathbun Regional Water Association permit #3663-R4 allows withdrawal from Rathbun Dam immediately downstream from gage at a maximum rate of 6,181 gpm (13.7 ft³/s).

WATER-QUALITY RECORDS

PERIOD OF RECORD.--Water years 1963-1969.

PERIOD OF DAILY RECORD.--
SPECIFIC CONDUCTANCE: Daily instantaneous values collected in conjunction with suspended-sediment samples, October 1968 to September 1969.
WATER TEMPERATURE: Daily instantaneous values collected in conjunction with suspended-sediment samples, October 1962 to September 1969.
SUSPENDED-SEDIMENT CONCENTRATION AND DISCHARGE: October 1962 to September 1969, October 1969 to September 1974. Beginning October 1969, suspended-sediment discharge records only, provided by U.S. Army Corps of Engineers.

Advanced Hydrologic Prediction Service

U.S. Army Corps of Engineers - Kansas City District