Peixoto Dam

Peixoto Dam, also known as Mascarenhas de Moraes Hydroelectric Plant, is a hydroelectric dam on the Grande River in the state of Minas Gerais, Brazil, about 20 km west of Delfinópolis.

Studies for a dam at the Peixoto site were first carried out in 1947 by the Companhia Paulista de Força e Luz, which obtained rights to develop the site in 1950. The dam was built between 1952 and 1957 with help from the United States and the dam dedicated on April 30, 1957 by Brazilian President Juscelino Kubitschek. The first two Francis turbine-generators came online in 1957, and eight more were installed by 1968, bringing the plant to its full capacity of 476 MW. Since 1973, the dam and hydroelectric power plant have been operated by Eletrobras Furnas. Peixoto was the first of a cascade of nine dams to be built on the Grande River.

The dam consists of a central concrete arch section flanked by gravity wings, totaling 50.6 m high and 600 m long, impounding the 145 km long Represa de Peixoto (Peixoto Reservoir), with a storage capacity of 4.04 km3 and a useful capacity of 2.50 km3. The 210 x power station is located on the south side of the dam and consists of ten vertical Francis turbines.

Water is released from the dam through the power plant and two spillways. The service spillway, located on the north side of the dam, is an overflow structure with 11 gates, providing a maximum capacity of 9350 m3/s. The auxiliary spillway is located to the south and consists of a concrete chute controlled by two gates, with a capacity of 3100 m3/s.