USGS Water-Year Summary 2024
08104900 South Fork San Gabriel River at Georgetown, TX
LOCATION - Lat 30°37'32", long 97°41'27" referenced to North American Datum of 1927, Williamson County, TX, Hydrologic Unit 12070205, on right bank at downstream side of downstream bridge on Interstate Highway 35, 1.1 mi southwest of the courthouse at Georgetown, and 2.4 mi upstream from mouth.
DRAINAGE AREA - 133 mi².
REVISIONS HISTORY - WDR TX-76-2: Drainage area. WDR US-2007: 2001 (M).
SURFACE-WATER RECORDS
PERIOD OF RECORD - Oct. 1947 to Sept. 1948, Sept. 1962 to Oct. 1967 (occasional low-flow measurements). Dec. 1967 to current year.
PERIOD OF RECORD, Water-Quality.--
CHEMICAL DATA: Oct. 1962 to June 1963, Apr. 1978 to Feb. 1979.
BIOCHEMICAL DATA: Oct. 1962 to June 1963.
GAGE -
Water-stage recorder. Satellite telemetry at station.
Datum of gage: 687.936 ft NAVD88 based on a Level 2 Static GNSS survey processed through OPUS, Ref Frame NAD83 (2011)(EPOCH:2010.0000) ITRF2014 (EPOCH:2023.6266) and Geoid 18. The survey was completed on August 17th, 2023, while occupying a TRM referenced to local gage datum via differential levels.
Prior to 8/17/2023, the datum of the gage was 687.72 ft NGVD29.
EXTREMES OUTSIDE PERIOD OF RECORD - Maximum stage since at least 1887, about 41 ft Apr. 24, 1957, from information by local residents.