USGS Water-Year Summary 2021
06464100 KEYA PAHA RIVER NEAR KEYAPAHA, SD
LOCATION - Lat 43°07'45", long 100°06'24" referenced to North American Datum of 1927, in NW 1/4 SW 1/4 SW 1/4 sec.17, T.96 N., R.78 W., Tripp County, SD, Hydrologic Unit 10150006, on left bank at downstream side of highway bridge, 2.0 mi northeast of Keyapaha, and 2.0 mi upstream from Sand Creek.
DRAINAGE AREA - 535 mi² of which 3 mi² probably is noncontributing.
- WDR SD-10-1: Drainage area.
PERIOD OF RECORD - October 1981 to current year.
GAGE - Water-stage recorder and crest-stage gage. Datum of gage is 2,231 ft above NAVD88, from topographic map. Prior conversion to NAVD88, datum was published as 2,230 ft above NGVD29, from topographic map.
EXTREMES OUTSIDE PERIOD OF RECORD - Flood of 1952 reached a stage of about 14 ft, present datum, from information by local residents.