Septic Tank Companies in California
559 septic service companies across 264 cities — approximately 12% of California homes use septic systems
California's onsite wastewater treatment systems are regulated under the State Water Resources Control Board (SWRCB) through its Water Quality Control Policy for Siting, Design, Operation, and Maintenance of Onsite Wastewater Treatment Systems (OWTS Policy), with local administration handled by county environmental health departments. California's extraordinary geographic diversity — from the Central Valley's clay soils to the Sierra Nevada's granite bedrock to the coastal bluffs of Mendocino — means septic design requirements vary enormously across the state's 58 counties. Earthquake activity, wildfire zones, and stringent groundwater protection rules near waterways add layers of regulation that make California one of the most complex states for septic system permitting.