The California we know today, with a population of nearly 40 million people and agricultural land covering millions of acres, would not be possible without major investments in human-engineered infrastructure projects that transport water and power throughout the state and reduce flood risk. Investing in resilient watersheds and ecosystems, or our “green infrastructure,” is just as important to the sustainability of our water supplies and flood management as the concrete structures that move water throughout the state.

California Aqueduct
California Aqueduct

Water Delivery Infrastructure

The State Water Project (SWP), developed in the 1960s, is the largest state-built, multi-benefit water delivery system in the United States. Because California receives most of its precipitation in the watersheds of the northern Sierra Nevada mountains, the SWP was designed and built to collect some of that water abundance in the north and distribute it to more arid parts of the state.

The SWP is a complex system of 36 storage facilities, 26 dams, 21 pumping plants, five hydroelectric power plants, four pumping-generating plants, and approximately 700 miles of canals, tunnels, and pipelines engineered to safely store and deliver water. Moving millions of acre-feet of water across our great state requires pumping plants that use significant amounts of power.  In fact, the SWP is the largest consumer of electricity in California, but also the 4th largest producer of clean, emission-free hydroelectricity. The Edmonston Pumping Plant, south of Bakersfield, is the world’s tallest water lift, pumping water 1,926 feet up and over the Tehachapi Mountains into Southern California.

In addition to supplying water to 27 million Californians and 750,000 acres of farmland, the SWP provides flood management benefits, recreational opportunities, and water for fish and wildlife. Learn more about how California’s water supply and delivery system works.

Dutch Slough Tules
Dutch Slough

Nature’s Water Infrastructure

The benefits of our “gray infrastructure” depend on the health of California’s “green infrastructure,” namely our watersheds and the ecosystems therein. A watershed is an area of land that catches and channels rainfall and snow melt into creeks, streams, and rivers, and eventually to reservoirs, bays, the ocean, or underground aquifers. Watersheds are an integral part of California’s water system. As climate change advances, watersheds are even more important to the reliability, quantity, and quality of California’s water supplies. Investing in green infrastructure projects like ecosystem restoration is a cost-effective way to protect and maintain healthy watersheds in California. Also, tidal and floodplain restoration projects are important strategies to reduce flood risk. 


DWR takes a science-driven approach to integrate water delivery infrastructure projects with watershed restoration projects to support the long-term vitality of California’s thriving economy, communities, and ecosystems. Resilient watersheds are the foundation of water resource sustainability. The integrated management of our natural and engineered water systems ensures that we can provide clean water, protect habitats, prevent flooding, reduce pollution, and create recreational opportunities long into the fut


Green Infrastructure Projects

DWR utilizes the latest science and technology in developing green infrastructure projects such as: