Algal Growth Caused by Pollution in Furnas Lake, Brazil – May 14th, 2009
Furnas is an artificial lake, dam and power plant in northern Minas Gerais state, Brazil. There is also a small city near the dam with the same name, Furnas, built to house the workers in the dam construction.
The building of the dam began in 1957 and was completed in 1963. It is built on the canyon of the Grande River, below its joining with the Sapucaí River. The canyon is 127 meters high, 550 meters long, and 15 meters wide at its crest.
The formation of the enormous reservoir started in 1963. Its area is 1,473 square kilometers, almost half of the Brazilian coastline. It borders 34 municipalities. The volume of water is seven times that of Guanabara Bay.
In the reservoir the normal maximum water level is 750 meters, with the total volume of water 22590 x 106 cubic meters. The main objectives of the dam and the lake are the production of electricity and the regulation of the flow of the Grande River.
Tourism has not caught on in the 139 municipalities that dump their sewage into the lake. Together with this dumping there is the agricultural runoff causing proliferation of algaes, making the lake appear bright yellow and green here, and future damage to the ecological balance of the fauna of the lake.