In the late 1950s, work began on the California Aqueduct, a massive system of canals and pipelines designed to bring water from Northern California to growing cities in the parched south. The East Branch of the aqueduct passes over the San Bernardino Mountains through a complex arrangement of pumping stations, reservoirs and power stations. The aqueduct feeds Silverwood Lake, a large reservoir created by the construction of a dam on the northern flank of the San Bernardinos in 1973. From Silverwood, the water passes through the mountains via the San Bernardino Tunnel, and drops down to the Devil Canyon Power Plant in the San Bernardino Valley, using the enormous hydraulic head afforded by the mountains to generate up to 276 MW of power.