USGS Water-Year Summary 2021
06479215 BIG SIOUX RIVER NEAR FLORENCE, SD
LOCATION - Lat 45°10'51", long 97°11'09" referenced to North American Datum of 1927, in NE 1/4 NE 1/4 NE 1/4 sec.17, T.120 N., R.52 W., Grant County, SD, Hydrologic Unit 10170202, on right bank near downstream side of county bridge, 11.0 mi northeast of Florence, and 2.2 mi upstream from Indian Creek.
DRAINAGE AREA - 68.3 mi².
- WDR SD-10-1: Drainage area.
PERIOD OF RECORD - June 1984 to current year.
GAGE - Water-stage recorder and crest-stage gage. Datum of gage is 1,781.54 ft above NAVD88. Prior to conversion to NAVD88 datum of gage was published as 1,780.57 ft above NGVD29.
EXTREMES FOR PERIOD OF RECORD - Minimum daily discharge, 0.00 ft³/s, Aug. 9, 1985, no flow for some days in water years 1985, 1990-91, 2004, 2013, and 2018.