San Mateo County, CA Water Use Rules: Recycled Water Rules (2026)

140, adopted with the rest of the current Cross-Connection Control chapter under Ordinance No. 1 of the State Water Resources Control Board's Cross-Connection Control Policy Handbook (CCCPH), so any covered system must satisfy both the state definitions and whatever the local Plumbing Code separately requires for installation and testing. 020) on behalf of the County Health Officer. 030, its reach is not limited to unincorporated territory the way most county land-use rules are: it covers every facility, dwelling, or piping system within the service area of a water supplier that has an agreement with the county for backflow-prevention enforcement, plus any water user's premises anywhere in San Mateo County where contaminated backflow could reach the public drinking supply.

130: the Division may require a water supplier to discontinue service to a noncompliant facility, and may issue administrative orders and fines of up to $500 for a violation, with each day of continued noncompliance treated as a separate violation. A notice of fine is served by certified mail, and the recipient has ten calendar days to appeal in writing to the Director, whose decision is final. Unpaid fines may be referred to a collection agency and must be cleared before any registration or authorization under the chapter is issued or renewed.