Septic permit rules and requirements in California
In California, the state sets the rule. The septic permit comes from your county environmental health department. For some systems the state issues it itself. The code is Water Quality Control Policy for Siting, Design, Operation and Maintenance of Onsite Wastewater Treatment Systems (OWTS Policy). OWTS Policy § 1.0, Definitions ("Local agency", "Permit") · checked 2026-09-12
State Water Resources Control Board
Writes the rules
checked 2026-09-23
Your county environmental health department
Issues the permit
checked 2026-09-12
Water Quality Control Policy for Siting, Design, Operation and Maintenance of Onsite Wastewater Treatment Systems (OWTS Policy)
Code section
checked 2026-09-23
Who decides a septic permit in California
Your county environmental health department issues an ordinary residential permit. For some systems the state issues it itself. The state sets the floor through the State Water Resources Control Board.
The policy says a permit is a paper the local office issues. This office can be a county, a city or a district.
OWTS Policy § 1.0, Definitions ("Local agency", "Permit") · checked 2026-09-12
The office publishes its own page on this: State Water Resources Control Board — Onsite Wastewater Treatment Systems (OWTS) Policy.
The page carries no canonical tag. This is the web address for the board's own OWTS Policy page.
State Water Resources Control Board — Onsite Wastewater Treatment Systems (OWTS) Policy · checked 2026-09-23
The floor state law sets
The rules that govern every septic system in California are Water Quality Control Policy for Siting, Design, Operation and Maintenance of Onsite Wastewater Treatment Systems (OWTS Policy). Every local permit is issued under them.
The policy lets septic systems keep working. It protects water quality and public health. It sets rules for siting, design, operation and maintenance.
State Water Resources Control Board — OWTS Policy · checked 2026-09-23
California counties on this site
We have not published a California county page yet. A county earns a page when we hold facts unique to it. Until then this page is the answer for every county in the state.
Telling us your county is how we decide which one to build next.
Sources
State records only. Each figure above has a government source and a checked-on date. County figures live on the county pages.
Verify before you act. Septic rules are set locally and they change. Check anything here with your county environmental health department before you spend money on it.