Water School

The level of water in all lakes fluctuates, raising during years of higher amounts of rainfall and snowmelt and falling during periods of drought. The Environmental Protection Agency has been measuring the fluctuations of the Great Lakes, the largest natural lakes in the United States, since the 1860s. Similarly, water levels in reservoirs, human-made lakes, fluctuate because of evaporation, a lack of rainfall, water supply use, and water flow requirements. Levels tend to be relatively lower in ...

Possum Kingdom Lake, located on the main stem of the Brazos River northwest of Fort Worth, was the first water supply reservoir constructed in the Brazos River basin. Located in Young, Palo Pinto, Stephens, and Jack counties, the construction of the Morris Sheppard Dam was begun in 1938 and completed in 1941 with the aid of the Works Progress Administration Program.Possum Kingdom Lake covers an area of 16,716 acres with 219 miles of shoreline. The reservoir holds approximately 556,340 ...

DeCordova Bend Dam and Lake Granbury were constructed by the Brazos River Authority and are maintained and operated by the BRA as a source of water supply.Construction of the project began in December 1966 and was completed in September 1969. The reservoir provides 136,326 acre-feet of storage capacity for conservation of flood and storm waters to meet the requirements of municipalities, industries, agriculture, and mining.  The reservoir has a permitted yield of 64,712 acre feet. ...

Lake Limestone, located on the upper Navasota River in Limestone, Robertson and Leon counties, is a water supply reservoir built by the Brazos River Authority in 1978. Construction of the reservoir was made possible through the sale of water to Texas Electric Utilities to be used by their lignite-burning electric plants in the area. To view a copy of the Lake Limestone state permit, click here.Water from the reservoir is supplied for similar use at a NRG steam-electric plant just east of Lake Li...

A spillway part of a dam that is designed to allow water to flow freely over the dam during floods. Spillways may be used on dams with floodgates as an additional means to control release of water during flooding.  A spillway may also be used as the main area of water release from a dam, allowing water to flow through the spillway only when the reservoir is full.

Maps of BRA lakes may be found online by visiting each reservoirs' web page: Possum Kingdom, Granbury and Limestone.  Printed maps of each reservoir are available free of charge at each lake office or by calling the Public Information Office at (888) 922-6272.