Cal. Health & Safety Code § 116552

The State Water Resources Control Board shall not issue a permit to a public water system or amend a valid existing permit to allow the use of point-of-use or point-of-entry treatment unless the State Water Resources Control Board determines, after conducting a public hearing in the community served by the public water system, that there is no substantial community opposition to the installation of the treatment devices. The issuance of a permit pursuant to this section shall be limited to not more than three years or until funding for centralized treatment is available, whichever occurs first.