Bareilles

I. BACKGROUND

A. Regulatory Background The Porter-Cologne Water Quality Control Act (§ 13000 et seq.) (Porter- Cologne Act) “is the principal law governing water quality regulation in California.” (Monterey Coastkeeper, supra, 76 Cal.App.5th at p. 8.) “The Legislature designated the State Board and nine regional water quality control boards . . . as the agencies with primary responsibility for the regulation of water quality under the Porter-Cologne Act. (§ 13001.) The State Board formulates and adopts statewide policy for water quality control, allocates funds, and oversees the activities of the regional water boards. (§§ 13140, 13320.) Each regional water board is responsible for, among other things, water quality protection, permitting, inspection, and enforcement actions within its region. (§ 13225, subd. (a).)” (Monterey Coastkeeper, supra, 76 Cal.App.5th at p. 8.) One function of the regional boards is to regulate discharges of waste. (Monterey Coastkeeper, supra, 76 Cal.App.5th at p. 8.) As part of this function, the regional board may prescribe “ ‘waste discharge requirements’ ” (WDRs) to implement water quality control plans for any existing discharge or proposed…