Calaveras Lake (San Antonio River Basin)

Calaveras Lake with the power plant beside it (Photo from the owner's website)Calaveras Lake is located about fifteen miles southeast of San Antonio in Bexar County, on Calaveras Creek, a tributary of the San Antonio River. Together with the smaller Victor Braunig Lake, the Calaveras Creek Dam and Lake are owned and managed by CPS Energy of San Antonio (CPS – City Public Service) for cooling to a complex of power plants and recreational purposes. Authorization (Water Right Permit No. 2507) was issued by the State Board of Water Engineers on February 7, 1968. Construction of the dam started on September 1, 1967 and was completed in August 1969. Deliberate impoundment of water began in January 1969.

The dam is an earthfill embankment of 6,000 feet long with a maximum height of 70 feet. the top of the dam is at elevation, 498 feet above mean sea level. The spillway is located at the center of the dam and is a concrete ogee structure with crest at elevation, 460 feet above mean sea level. It is controlled by five tainter gates, each 44 feet wide by 27 feet tall. Therefore, the top of the gate is at elevation of 487 feet above mean sea level. The reservoir has a capacity of 63,200 acre-feet encompassing a surface area of 3,624 acres at the conservation pool elevation of 485 feet above mean sea level. The drainage area above the dam is only 65 square miles. However, the reservoir is partly filled with wastewater that has undergone both primary and secondary treatment at a San Antonio Water System treatment plant. Other source of water includes pumping from the San Antonio River.