BRAZORIA RESERVOIR. Brazoria Reservoir, an off-channel reservoir, is in the Brazos River basin six miles southwest of Angleton in central Brazoria County (at 29°03' N, 95°32' W). The project, owned and operated by Dow Chemical Company, is used for industrial water supply. It was designed by engineers Lockwood and Andrews, constructed by general contractor Gulf Bitulithic, and completed on May 1, 1954. Diversion of water from the Brazos began in April 1954. The storage reservoir has a capacity of 21,970 acre-feet and a surface area of 1,865 acres at a crest elevation of 31.07 feet above mean sea level. The reservoir level is maintained by water pumped from the Brazos River.