About CDA


The Chino Basin Desalter Authority (CDA) was formed as a Joint Powers Authority to manage the production, treatment, and distribution of highly treated potable water to cities and water agencies throughout its service area. CDA is composed of the following eight member agencies:

  • City of Chino
  • City of Chino Hills
  • City of Norco
  • City of Ontario
  • Inland Empire Utilities Agency (IEUA)
  • Jurupa Community Services District (JCSD)
  • Santa Ana River Water Company (SARWC)
  • Western Municipal Water District (WMWD)

The CDA purifies brackish groundwater extracted from the lower Chino Basin with the Chino I and II Desalter facilities and distributes the drinking water to its member agencies. The Chino I and II Desalters serve the dual purpose of providing a reliable water supply and managing groundwater quantity and quality in the region.

Chino Basin groundwater is the only water source for the CDA. Chino Basin is one of the largest groundwater basins in Southern California. Management of the Chino Basin is guided by the 1978 Judgment, the Peace Agreement (2000), and the Optimum Basin Management Program (2008 OBMP), updated every five years.

Most CDA member agencies purchase water from the Metropolitan Water District of Southern California (MWD) for potable water service. CDA member agencies also have take or pay contracts with CDA for 24,600 acre feet per year of water supply from the desalters. The more the desalters produce, the less the member agencies buy from MWD.

Main Benefits of the CDA

  • It represents a reliable, local source of drinking water produced by desalination
  • Improves water supply reliability through enhanced local supplies reducing dependency on MWD imported supplies
  • Salt and nitrates are removed from the groundwater basin to clean up the Chino Basin
  • Hydraulic control of groundwater is enhanced by the location of groundwater extraction wells. This helps prevent groundwater that is high in salinity and nitrates from spilling over the Chino Basin southern barrier into the Santa Ana River