Septic Tank Inspectors in Washington

Cities in Washington

Washington Septic Regulations

Washington septic systems are regulated by the Washington State Department of Health and local health jurisdictions under the On-Site Sewage System rules (WAC 246-272A). Permits are required for the installation, repair, and alteration of onsite sewage systems, and many counties require an inspection at time of property transfer or as part of a regular monitoring program.

• Onsite sewage system permits are issued by the local health jurisdiction (county health department) under DOH authority and require a site evaluation and soil assessment.
• Washington requires licensed installers and certified inspectors for onsite sewage system installation, repair, and inspection.
• WAC 246-272A establishes minimum setback distances from wells, surface waters, and property lines for all onsite sewage systems.
• Some Washington counties require a time-of-transfer or routine operational inspection, especially for systems near shellfish harvesting areas or critical aquifers.
• Systems must be designed to meet DOH standards based on site and soil conditions, including percolation test results and vertical separation to groundwater.
• Local health departments maintain records of permitted systems — contact the county health department for system records before purchasing property.

Source: Washington State Department of Health (DOH) / Local Health Departments