Mitchell Dam Mitchell Lake and Dam are located in Coosa and Chilton Counties on the Coosa River. The dam was constructed by the Alabama Power Company and began generating electricity for the region in 1923. The Federal Power Commission, created by Congress in 1920, granted its first license to Alabama Power Company in 1921, permitting it to construct a dam across the Coosa River. The location was downstream from Lay Dam near the town of Verbena at an isolated shoals area on the river called Duncan’s Riffle.
James Mitchell The dam was named for former Alabama Power president James Mitchell, an internationally connected electrical systems developer from Massachusetts. Mitchell had arrived in Alabama in 1911 to survey the state’s potential for hydroelectric power development. With financing from Great Britain, he created a holding company based in Canada called the Alabama Traction, Light & Power Company to consolidate electric power development interests in the state. These interests were eventually consolidated under the name of Alabama Power Company. Under Mitchell’s leadership, Lay Dam and the Gadsden and Gorgas steam plants were constructed. When Mitchell died in 1920, leadership of Alabama Power Company passed to Thomas W. Martin, an Alabama lawyer who helped Mitchell organize the company.
Because the Mitchell Dam site was located in a remote area on the Coosa River, a worker’s village had to be built before construction on the dam began. Following the example set at Lay Dam, facilities for workers included living quarters, schools, an infirmary, a dining hall, and recreational facilities. Construction on the dam began in July 1921. Teams of laborers cleared the reservoir lands and rights of way for transmission lines. The effort at Mitchell Dam went more quickly than at other similar Alabama Power facilities because the site had plenty of electricity from the recently completed Lay Dam upstream. Generating units one, two, and three went into service in August 1923. Unit four was added in 1949. Still in place, the first three units were deactivated in 1985 when units five, six, and seven were installed in a new powerhouse below the dam.
Construction of Mitchell Dam There are two types of lakes formed by the company’s hydroelectric plants: storage and “run-of-river.” The company seasonally varies the water levels on its storage lakes. Power production is enhanced by maintaining water at the highest levels in the summer months when demand for electricity is greatest. Lake levels are lowered in the fall and usually reach their lowest point in December to provide room for flood storage in anticipation of spring rains and to allow time for shoreline maintenance. Mitchell Lake, however, is a “run-of-river lake,” which means that lake levels remain fairly constant year round. Drought conditions, of course, have an effect on the water levels of both storage and run-of-river lakes.
Mitchell Dam generates electricity only when peak demand requires it or when market prices for electricity are favorable. Usually, hydro power is the most economical way for Alabama Power to generate electricity, because there are no fuel costs, but it cannot be used all of the time. During the drought of 2007, hydro generation across Alabama Power’s system of dams, including Mitchell Dam, was reduced significantly. Electricity generated at Mitchell Dam as well as at all other Alabama Power Company dams does not serve specific customers. Power from Mitchell Dam, along with the power from all company generating plants, is fed into the Southern Company power grid, and all customers draw their electrical power through substations connected to the grid.
Turbine at Mitchell Dam All Alabama Power Company lakes are licensed by the federal government for a period of 30, 40, or 50 years. At the end of the licensing period, the company must re-apply for a license. To be approved for re-licensing, the company must demonstrate that it has satisfied the regulations set by the Federal Energy Regulatory Commission. These regulations include generation requirements as well as minimum and maximum pool levels, flood control, environmental regulations, and provisions for recreation opportunities. The U.S. Army Corps of Engineers sets guidelines by which Alabama Power regulates its lake levels.
Mitchell Dam is a gravity concrete dam. This means that the dam is a completely concrete structure. Falling water from the upstream side of the dam turns turbines generating electricity. The dam is 1,277 feet in length and stands 106 feet high. Unit four generates 20,000 kilowatts and units five through seven generate 50,000 kilowatts each for a total of 170,000 kilowatts. The lake formed by Mitchell Dam is 14 miles long and covers 5,850 acres. The maximum depth at the dam is 90 feet and the volume of the lake is approximately 56 billion gallons. The watershed draining into the lake encompasses 9,827 square miles.
Mitchell Lake provides 147 miles of shoreline for permanent and vacation homes and recreational opportunities that include boating, fishing, swimming, and other outdoor activities. There are boating ramps, picnic facilities, nature trails, and restrooms available to the public. Like all power company lakes, Mitchell Lake offers some of the best fishing in the South. Species of fish found in the lake include several varieties of bass and crappie as well as catfish, sunfish, and walleye.
Atkins, Leah Rawls. “Developed for the Service of Alabama”:The Centennial History of Alabama Power Company, 1906-2006. Birmingham: Alabama Power Company, 2006.
Jackson, Harvey H., III. “Putting Loafing Streams to Work”: The Building of Lay, Mitchell, Martin, and Jordan Dams, 1910-1929. Tuscaloosa: University of Alabama Press, 1997.
Mitchell Lake Coosa River Recreation Map. Birmingham: Alabama Power Company, 2001.