USGS Water-Year Summary for Site 08104650

Click to hide Water-Year Summary instructions and information

Water-Year Summary reports summarize a year of hydrologic data in a printer-friendly format.
For water years 2014 onward, choose a water year and parameter and an on-demand Water-Year Summary report will be generated.
For water years 2006 through 2013, choose a water year and an Annual Water Data Report will be provided.
For water years 2005 and earlier, Annual Water Data Reports may be available in digital format.
Not all sites have reports available for every water year.

	Available Parameters
	62614 Elevation, lake/res, NGVD29(Mean)

Select a water year

Water year 2023: 2022-10-01 to 2023-09-30

Print this page

USGS Water-Year Summary 2023

08104650 Lake Georgetown near Georgetown, TX

LOCATION - Lat 30°40'03", long 97°43'38" referenced to North American Datum of 1927, Williamson County, TX, Hydrologic Unit 12070205, at North San Gabriel Dam, on North Fork San Gabriel River, 2.5 mi upstream from Middle Fork San Gabriel River, 3.7 mi northwest of Georgetown, and 4.4 mi upstream from confluence with South Fork San Gabriel River.

DRAINAGE AREA - 247 mi².

SURFACE-WATER RECORDS

PERIOD OF RECORD - Mar. 1980 to Sept. 2000 (contents furnished by U.S. Army Corps of Engineers), Oct. 2000 to Sept. 2002 (daily mean contents), Oct. 2002 to current year. . PERIOD OF RECORD, Water-Quality.-- CHEMICAL DATA: Oct. 1980 to Aug. 1989. BIOCHEMICAL DATA: Oct. 1980 to Aug. 1989.

GAGE - Water-stage recorder. Datum of gage is 0 ft above NGVD of 1929 (levels by U.S. Army Corps of Engineers). Prior to May 13, 1980, nonrecording gage at present site and datum. Satellite telemeter at station.

COOPERATION - Prior to Oct. 1, 2000, record of contents furnished by the U.S. Army Corps of Engineers and reviewed by the U.S. Geological Survey. A new capacity table, provided by the Texas Water Development Board, was put into use Oct. 1, 1995.

REMARKS - Records fair. The lake is formed by a rolled earthfill dam, 6,700 ft long, including the spillway. The lake was built for water conservation and flood control. The dam is owned by the U.S. Army Corps of Engineers. Deliberate impoundment began on Mar. 3, 1980. The spillway is an ungated broad-crested weir 1,000 ft long, located near right end of dam. The spillway for normal flood releases is a gated, 11-ft-diameter conduit, controlled by two 5- by 11-ft slide gates, located near the center of dam. The invert for the floodgate is 720.0 ft. A low-flow outlet, consisting of four 3- by 4-ft gates is located near the center of dam. The inverts of these gates are 735.0, 749.0, 763.0, and 777.0 ft. Data regarding dam are given in the following table:

                                                                              Elevation (feet)
Top of dam............................................................           861.0
Design flood..........................................................           856.2
Crest of spillway.....................................................           834.0
Top of conservation pool..............................................           791.0
Lowest gated outlet (invert of 11-foot conduit).................                720.0

Water-Quality data published as:

Site ID          Site name
304016097433101  Lake Georgetown Site AC
304006097452501  Lake Georgetown Site BC
304055097471301  Lake Georgetown Site CC

Some records listed in the "Period of Record" for surface water and water quality may not be available electronically.

EXTREMES FOR PERIOD OF RECORD - Mar. 1980 to Sept. 2002: Maximum contents, 136,900 acre-ft, Mar. 4, 1992; minimum contents after initial filling, 13,990 acre-ft, Oct. 15 Nov. 2, 2000; Mar. 1980 to current year: maximum elevation, 835.86 ft, Mar. 4, 1992; minimum elevation, 765.56 ft, Oct. 21, 2011.