It was created at 1976 to refrigerate the turbines of the Almaraz Nuclear Power Plant.

The refrigeration of the Almaraz nuclear power plant was the first reason for the construction of the reservoir.

The water is taken from the Tagus and cover a U-shaped circuit of 25 km which allows the cooling of the heat generated by the two nuclear reactors of the plant.

(See the illustration of the water circulation in Arrocampo) (...) The walls of thermic separation (pantallas de separación térmica in Spanish) (PST) are 11 km long and 8 m high (...).

[2] The Arrocampo ornithologic park is located in the municipality of Saucedilla, near the reservoir.