Well and Septic Systems
The Well and Septic Division staff reviews all development proposals that will rely on water wells or septic systems. They also review permit applications for septic system repair or upgrade. Their focus is on protecting health by ensuring that water wells are properly constructed and septic systems protect surface and groundwater quality. Sonoma County's soils are notoriously poor for septic systems, so this is a sometimes challenging mission.
Sanitation Sewer Information
A sanitary sewer system collects and transports waste from indoor plumbing fixtures to treatment plants.
Inspections are necessary to determine whether well or septic construction work is compliant with code requirements, and that the scope of work is in accordance with the related permits.
- Inspection Scheduling
Schedule and find out the results of your inspections in one of 3 ways.
- Well & Septic Inspection Codes
Find the 3 digit codes needed to schedule inspections.
Sonoma County Code
- Chapter 7 – Building Regulations
- Chapter 24 – Sewers and Sewage Disposal
- Chapter 25B – Water Well Construction Standards
- Full List of County Code Administered/Enforced by Permit Sonoma
The purpose of the Non-Standard Septic System Operational Permit and Monitoring (OPR) program is to monitor non-standard septic systems to ensure they are operating properly for the protection of public health and groundwater resources.
Permit Sonoma administers the county’s OPR program. The property owner’s role in the OPR program is to properly maintain and operate their septic system. Part of that responsibility is to submit biannual monitoring information to Permit Sonoma.
- Wet Weather Percolation and Groundwater Testing
Septic Systems: To protect groundwater from pollutants from septic systems, the Onsite Wastewater Treatment Systems (OWTS) Manual requires that wet weather groundwater table determinations be conducted under specific conditions.
- Dry Weather Well Testing
Water Wells: Sonoma County Code requires dry weather well testing for issuance of building permits for new dwellings located in marginal or scarce water zones.
Graywater is wastewater collected from showers, bathtubs, bathroom sinks, and clothes washing machines. Graywater does not include water from toilets, kitchen sinks, or dishwashers. Graywater can be routed to your landscape to help meet your irrigation needs.
The Board of Supervisors will be considering the revised OWTS Manual at an upcoming meeting early in 2023. With direction from the Board of Supervisors, the revised manual will be submitted to the local Regional Water Board for approval.