Mission and History

What We Do

The Water Replenishment District of Southern California (WRD) is the largest groundwater agency in the state of California, managing and protecting local groundwater resources for over four million residents. WRD's service area covers a 420-square-mile region of southern Los Angeles County, the most populated county in the United States. The 43 cities in the service area, including a portion of the City of Los Angeles, use about 250,000 acre-feet (82 billion gallons) of groundwater annually which accounts for approximately half of the region's water supply.

WRD ensures that a reliable supply of high-quality groundwater is available through the use of recycled water and stormwater capture. WRD is responsible for monitoring and testing groundwater throughout the region using effective management principles.

Visit the Projects and Programs section of this site to learn more about WRD's individual water projects and programs.

You can also view WRD's Our Road to Water Independence History booklet here.


WRD Mission

"To provide, protect, and preserve safe and reliable high-quality groundwater."


WRD History

WRD was formed by a vote of the people in 1959 for the purpose of protecting the groundwater resources of the Central and West Coast Groundwater Basins. Prior to the formation of the District in 1959, unregulated and unmanaged over-pumping caused many water wells to go dry. Along the coastline, groundwater levels dropped below sea level, allowing the salty ocean water to seep into and contaminate the freshwater aquifers.

Today, WRD protects the basins through artificial groundwater replenishment, ensuring that aquifers maintain healthy levels. WRD further protects the basins from seawater intrusion by injecting water into wells along the coastline to keep the ocean from further contaminating the fresh groundwater aquifers. Finally, WRD routinely monitors the groundwater to ensure the quality meets all health standards.

WRD celebrated 60 Years of Groundwater Replenishment on November 2019. Click on the image below to learn more about our work: