USGS Water-Year Summary 2023

08090900 Lake Granbury near Granbury, TX

LOCATION - Lat 32°22'27", long 97°41'20" referenced to North American Datum of 1927, Hood County, TX, Hydrologic Unit 12060201, at right end of spillway of DeCordova Bend Dam on the Brazos River, 2.6 mi upstream from Fall Creek, 7.5 mi southeast of Granbury, and at mile 542.5.

DRAINAGE AREA - 25,679 mi² of which 9,566 mi² probably is noncontributing.

REVISIONS HISTORY - WDR TX-76-2: Drainage area.

SURFACE-WATER RECORDS

PERIOD OF RECORD - Oct. 1968 to Sept. 2010 (contents), Oct. 2010 to current year. PERIOD OF RECORD, Water-Quality.-- CHEMICAL DATA: Feb. 1975 to Sept. 1977. BIOCHEMICAL DATA: Feb. 1975 to Sept. 1977. BIOLOGICAL DATA: Feb. 1975 to Aug. 1976. PESTICIDE DATA: Feb. 1975 to Aug. 1976.

GAGE - Water-stage recorder. Datum of gage is 1.11 ft below NGVD of 1929 (Brazos River Authority Datum) and 1.23 ft below NAVD of 1988. To obtain elevations in NAVD1988, add 1.23 ft. Satellite telemeter at station.

REMARKS - Some records listed in the "Period of Record" for surface water and water quality may not be available electronically. The lake is formed by an Ambursen-type concrete and earthfill dam 2,256 ft long, including a 932 ft concrete spillway. The dam was completed on Aug. 30, 1969, and deliberate impoundment began Sept. 15, 1969. The spillway consists of sixteen 36- by 35-ft tainter gates and two 7- by 8-ft sluice gates. Outflow through the sluice gates discharge into a bay where the outflow is then controlled by two 4- by 4.5-ft sluice gates with inverts at 625.8 ft. Flow is affected at times by discharge from the flood-detention pools of twelve floodwater-retarding structures with a combined detention capacity of 13,940 acre-ft. These structures control runoff from 53.9 mi² in the East Keechi, Kickapoo, and Ruckers Creeks drainage basins. The lake was built by the Brazos River Authority for the conservation of water for irrigation, municipal, and industrial uses. Water is also diverted into Squaw Creek Reservoir (station 08091730, conservation pool storage 151,030 acre-ft). The City of Granbury returns wastewater effluent into Lake Granbury. Conservation pool storage is 129,011 acre-ft. Data regarding the dam are given in the following table:

                                                                            Elevation (feet)
Top of dam............................................................           706.5
Top of tainter gates (design flood)...................................           693.0
Crest of spillway.....................................................           658.0
Lowest gated outlet (invert)..........................................           640.0

Water-quality records available from Sept. 1970 to Aug. 2006 were published separately as:

Site ID                Site name
322227097412101  Lk Granbury Site AC nr Granbury, TX
322231097412001  Lk Granbury Site AL nr Granbury, TX
322341097420601  Lk Granbury Site BC nr Granbury, TX
322337097415401  Lk Granbury Site BL nr Granbury, TX
322345097421901  Lk Granbury Site BR nr Granbury, TX
322537097414501  Lk Granbury Site CC nr Granbury, TX
322422097423901  Lk Granbury Site DC nr Granbury, TX
322437097423901  Lk Granbury Site DL nr Granbury, TX
322417097423801  Lk Granbury Site DR nr Granbury, TX
322458097443101  Lk Granbury Site EC nr Granbury, TX
322619097463301  Lk Granbury Site FC nr Granbury, TX
322703097451401  Lk Granbury Site GC nr Granbury, TX
322834097470801  Lk Granbury Site HC nr Granbury, TX
322819097483201  Lk Granbury Site IC nr Granbury, TX
323318097480101  Lk Granbury Site JC nr Granbury, TX
323435097492001  Lk Granbury Site KC nr Granbury, TX
322224097414801  Lk Granbury Site P1 nr Granbury, TX

EXTREMES FOR PERIOD OF RECORD - Maximum contents, 158,800 acre-ft, Mar. 27, 1977, elevation, 693.60 ft; minimum contents since normal operating level was reached in Oct. 1969, 97,600 acre-ft, Aug. 9, 1978, elevation, 685.28 ft; minimum elevation, 681.46 ft, June 22, 2014.