Ocean Plan Requirements for Seawater Desalination Facilities

On May 6, 2015, the State Water Board adopted an amendment to the Water Quality Control Plan for Ocean Waters of California (Ocean Plan) to address effects associated with the construction and operation of seawater desalination facilities (Desalination Regulations). The Desalination Regulations support the use of ocean water as a reliable supplement to traditional water supplies while protecting marine life and water quality. The Desalination Regulations, found in Chapter III.M of the Ocean Plan, provide a uniform, consistent process for permitting seawater desalination facilities statewide. In doing so, it provides direction for regional water boards when permitting new or expanded facilities and outlines specific implementation and monitoring and reporting requirements. The Office of Administrative Law approved the Desalination Regulations on January 28, 2016. The United States Environmental Protection Agency approved the portions of the Desalination Regulations that implement the federal Clean Water Act on April 7, 2016. Therefore, the Desalination Regulations are fully in effect.

The Desalination Regulations require new or expanded seawater desalination plants to use the best available, site, design, technology, and mitigation measures feasible to minimize intake and mortality of all forms of marine life. Based on the best available science, the Desalination Regulations identify preferred technologies; however, alternative intake and disposal methods can be used if demonstrated to be as protective of marine life as the preferred technologies. Additionally, the Desalination Regulations require mitigation measures to address harmful impacts on marine life that occur after a desalination facility uses the best available site, design, and technology feasible. Feasibility considerations regarding site, design, technology, and mitigation measures take into account economic, environmental, social, and technological factors and whether something is capable of being accomplished in a successful manner within a reasonable period of time.