USGS Water-Year Summary 2025

05451700 Timber Creek near Marshalltown, IA

LOCATION - Lat 42°00'31.95", long 92°51'08.71" referenced to North American Datum of 1983, in NW 1/4 SW 1/4 SE 1/4 sec.08, T.83 N., R.17 W., Marshall County, IA, Hydrologic Unit 07080208, on left bank 20 ft upstream from bridge on Shady Oaks Road, 3.0 mi southeast of Marshalltown, and 3.6 mi upstream from mouth.

DRAINAGE AREA - 118 mi².

REVISIONS HISTORY -

WSP 1708: 1950-1955, 1957-1959.
Revisions: Gage datum was revised to 856.62 ft NAVD88 on September 15, 2022, as determined by a GNSS Level II survey. Gage datum was previously published in error as 849.44 ft NGVD29 (furnished).

The period of Jun. 26, 2023- Nov. 1, 2023 was revised. Good data was deleted out of the stage record on Sept. 19 resulting in a gap in discharge. The edit was revised to only delete the spike in the data and prevent a gap. The -0.12ft. shift that ended on 9/7/2023 was revised to end on 7/12/2023 so that computed discharge would better align with what field notes indicated on Aug. 28.

SURFACE-WATER RECORDS

PERIOD OF RECORD - Discharge records from October 1949 to current year.

GAGE - Water-stage recorder. Datum of gage is 856.62 ft above North American Vertical Datum of 1988. Prior to October 1, 1991, at site 700 ft upstream at same datum.

REMARKS - Accuracy of records is discussed in the annual Station Analysis archived at the USGS IA Water Science Center.

EXTREMES OUTSIDE PERIOD OF RECORD - Flood in June 1947 reached a stage of 16.8 ft, discharge 5,700 ft³/s.