Water Supply


Padre Dam imports 100% of our drinking water supply from the San Diego County Water Authority (SDCWA)

How Our Water Is Imported

Our water supply depends on a 1922 agreement between seven western states as well as infrastructure (i.e. aqueducts, pipelines) operated by federal, state and regional agencies. The water Padre Dam imports comes from the State Water Project and the Colorado River Aqueduct. Water travels through over 600 miles of aqueducts and 1,100 miles of pipeline to get to San Diego County.

Padre Dam has a large infrastructure of its own to provide water to your home, including over 300 miles of water mains - enough pipe to stretch from San Diego to Phoenix.

Supply Diversification

Once 95% reliant on MWD water, the San Diego County Water Authority has made strides over several decades to diversify its supply portfolio. By 2020, local water supplies including the Carlsbad Desalination Plant, recycled water, groundwater and surface water reservoirs are projected to meet more than a third of the region’s water supply demands. The adjacent chart shows the goal for supply diversification into 2035.


Recycled water is an important part of San Diego County's future water supply. Every drop of recycled water used for non-potable use saves drinking water sources. Padre Dam produces two million gallons of recycled water a day at our Water Recycling Facility. Our recycled water provides irrigation water throughout Santee and provides the water that fills Santee Lakes.

The future of recycled water: potable reuse

Potable reuse projects are local, drought-proof sources of water which are projected to make up 17% of San Diego County’s drinking water supply by 2035. Padre Dam is currently working with Helix Water District, the City of El Cajon and the County of San Diego on the East County Advanced Water Purification Project. This project would purify recycled water in order to create up to 30% of East County’s drinking water supply. Together with projects including Pure Water San Diego and Pure Water Oceanside, the East County Advanced Water Purification Project will play a crucial part in reducing San Diego County’s reliance on imported water.

Increasing San Diego County's Water Supply Reliability through Supply Diversification

SDCWA Updated Source Water Graphic 2022