California Code, Health and Safety Code - HSC § 4762.1

All connections of lateral or other sewerlines to the sewerage system of the district, whether within or without any city, shall be made at points and in the manner to be directed by the engineers of the district under instructions from the district board, subject to such terms and conditions as the district board may prescribe. The district board may prescribe standards for installation and maintenance of laterals or sewerlines connecting to the sewerage system of the district, including, but not limited to, installation and maintenance by property owners of cleanouts and backflow protective devices.