The California State Water Project, commonly known as the SWP, is a water management project under the supervision of the California Department of Water Resources. The SWP is the world's largest publicly built and operated water and power development and conveyance system, providing drinking water for more than 23 million people and generating an average of 6,500 GWh of hydroelectricity annually. However, as the largest single consumer of power in the state, its net output in an "average" rainfall year is 5,100 GWh.