 The pumping forebay, which is separated from the main reservoir by a dam located downstream from the Castaic Power Plant, functions in connection with the pumped storage operations of the plant.This assures the availability of at least of water which can be pumped back to Pyramid Lake by the use of off peak energy when economical to do so.The pumping function at Castaic hydroelectric plant provides additional water for power generation beyond the supply of water available from the flow of the State Aqueduct.