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CWA 316(b) Policy Adoption and Amendments

Ocean Standards - CWA §316(b) Regulation


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On May 4, 2010 the State Water Board adopted a Policy on the Use of Coastal and Estuarine Waters for Power Plant Cooling (Policy). The administrative record for the Policy was approved by the Office of Administrative Law (OAL) on September 27, 2010. The Policy became effective on October 1, 2010 when the California Environmental Quality Act Notice of Decision was submitted to the Secretary of Resources.

The Policy establishes technology-based standards to implement federal Clean Water Act section 316(b) and reduce the harmful effects associated with cooling water intake structures on marine and estuarine life. The Policy applies to the 19 existing power plants (including two nuclear plants) that currently have the ability to withdraw over 15 billion gallons per day from the State’s coastal and estuarine waters using a single-pass system, also known as once-through cooling (OTC). Closed-cycle wet cooling has been selected as Best Technology Available (BTA). Permittees must either reduce intake flow and velocity (Track 1) or reduce impacts to aquatic life comparably by other means (Track 2).

The Policy is implemented through an adaptive management strategy by which the standards can be achieved without disrupting the critical needs of the State’s electrical generation and transmission system. A Statewide Advisory Committee on Cooling Water Intake Structures (SACCWIS) has been established to review implementation plans and schedules and provide recommendations to the State Water Board at least annually. The State Water Board will consider SACCWIS’s recommendations and make modifications to the Policy, as appropriate. The permittees’ NPDES permits will be reissued or modified to conform with the Policy.

Other Policy-Related Documents

Policy Amendments

Policy Adoption

Questions or Comments about Power Plant Once-Through Cooling Regulation?

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