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.
USGS Water-Year Summary 2024
08088440 Possum Kingdom Lake at Sandy Beach near Graford, TX
LOCATION - Lat 32°53'19", long 98°31'26" referenced to North American Datum of 1927, Palo Pinto County, TX, Hydrologic Unit 12060201, on left bank upstream of boat ramp in Brazos River Authority Public Area No. 6.
DRAINAGE AREA - 23,596 mi² of which 9,566 mi² probably is noncontributing.
SURFACE-WATER RECORDS
PERIOD OF RECORD - Oct. 2005 to current year.
GAGE - Water-stage recorder. Datum of gage is 0.00 ft above NGVD of 1929 and 0.79 ft below NAVD of 1988. To obtain elevation values in NAVD 1988, add 0.79 ft. Satellite telemeter at station.
REMARKS - The lake is formed by a reinforced concrete dam, Ambursen-type, massive buttress with flat-slab deck, a controlled spillway, two bulkhead sections, and an earthen-dike section. Total length of dam is 2,740 ft long. The dam, owned by the Brazos River Authority, was completed and storage begun Mar. 21, 1941. The spillway has nine roof-weir gates (modified bear-trap type) that are 73.66 x 13 ft each and are designed to discharge about 100,000 ft³/s at an elevation of 1,000 ft. The outlet works consist of one controlled 54-in diameter conduit. Water is used for power development, irrigation, municipal, industrial, and recreational purposes. Two generators located in the powerhouse at dam can produce 22,500 kilowatts at an elevation of 1,000 ft (Generators decommissioned). Eleven major reservoirs, with a combined capacity of 607,800 acre-ft, largely regulate the inflow. Flow is affected at times by discharge from the flood-detention pools of 12 floodwater-retarding structures with a combined detention capacity of 24,710 acre-ft. These structures control runoff from 108 mi². Conservation pool storage is 540,340 acre-ft. Data regarding the dam are given in the following table:
Elevation (feet) Top of dam.............................................................. 1,024.0 Design flood (top of gates)............................................. 1,000.0 Crest of spillway....................................................... 987.0 Invert of penstock...................................................... 911.5 Lowest gated outlet (invert of 54-inch conduit)......................... 874.8
EXTREMES FOR PERIOD OF RECORD - Maximum elevation, 1,000.12 ft, Mar. 18, 2020; minimum elevation, 984.05 ft, Sept. 23,
2014.
