USGS Water-Year Summary 2023
16208000 South Fork Kaukonahua Stream at East Pump, near Wahiawa, Oahu, HI
LOCATION - Lat 21°29'19.7", long 157°59'45.8" referenced to North American Datum of 1983, Honolulu County, HI, Hydrologic Unit 20060000, on the left bank of the upstream side of the dam at East Pump Reservoir, 2.3 miles east of Wahiawa Post Office, and 7.1 miles north of Waipahu.
DRAINAGE AREA - 4.10 mi². from automated delineation using 10-meter National Elevation Dataset digital elevation model data dated 09/2006 and Watershed Boundary Dataset dated 05/2008, using UTM Zone 4 projection, NAD 83 horizontal datum.
REVISIONS HISTORY - WDR HI-10-1: Drainage Area. On May 28, 2019, instantaneous discharge values were revised from March 28, 2018 to June 29, 2018, September 25, 2018, and October 30, 2018. On May 1, 2020, instantaneous discharge values below 2.12 ft³/s were revised from January 6-16, 2020.
SURFACE-WATER RECORDS
PERIOD OF RECORD - July 1957 to June 1963, water years 1963-64 (annual maximum), July 1964 to September 2004, October 2005 to September 2011, September 2013 to current year.
GAGE - Water-stage recorder and Ogee-type dam control. Datum of gage is 860.35 feet above mean sea level (from U.S. Coast and Geodetic Survey trig station).
EXTREMES FOR PERIOD OF RECORD - Maximum discharge, 6,070 ft³/s, December 11, 2008, gage height, 12.60 feet, from rating curve extended above 1,100 ft³/s on basis of computation of peak flow over dam; no flow at times.