Formation of CDA

The Chino Basin Desalter Authority (CDA) was formed under a Joint Exercise of Powers Agreement (JPA) on September 25, 2001, by a group of seven local agencies, including:

  • 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 was formally admitted to the CDA membership by the CDA Board on April 2, 2009, bringing the total number of member agencies to eight.


The Desalters were established to treat contaminated groundwater in the southern portion of the Chino Basin, and to help the Chino Basin Watermaster achieve “hydraulic control” of the basin to stop the flow of contaminated groundwater into the Santa Ana River. The Chino I Desalter commenced operation in 2001, and was expanded in 2005. The Chino II Desalter became operational in 2006, and was expanded in 2010 to add an extra 10.5-mgd capacity, which will be fully operational with the completion of other Phase 3 Expansion Project components.