Aug 17, 2019
As of August 15, 2019, the Sonoma County Onsite Wastewater Treatment System (OWTS) Manual version 7.0 is in effect. Customers are hereby advised that any septic applications will be required to comply with the provisions of the OWTS Manual version 7.0. Customers are further advised of the following updates to Permit Sonoma’s permitting procedures:
The Onsite Waste Treatment Systems (OWTS) Manual provides the regulations, procedural and technical details governing individual onsite wastewater treatment systems (also referred to as septic systems). State law mandates the State Water Resources Control Board (State Water Board) adopt standards for regulation of onsite waste treatment systems ( State Water Board OWTS Policy).
The OWTS Manual complies with the State Water Resources Control Board OWTS Policy Tier 2 Local Area Management Program (LAMP) requirements. OWTS Manual The OWTS Manual (link) and associated documents (Links) are presented below.
Manual Broken Into Sections / Accessible Version: Each document below is in PDF format and is under 550 kB unless otherwise noted. California Plumbing Code Memorandum OWTS Cover and Table of Contents
Section 1 – General Section 2 – Sewer Connection Required
Section 3 – Acronyms and Definitions Section 4 – Criteria for All OWTS
Section 5 – Abatements, Abandonments and Repairs of Failing Systems
Section 6 – Requirements for Approval of Building Permits
Section 7 – Site Evaluation Methods and Investigation Requirements
Section 8 – Criteria for OWTS Components
Section 9 – Criteria for Standard OWTS
Section 10 – Criteria for Water Reuse
Section 11 – Criteria for Commercial, Industrial, and Institutional OWTS
Section 12 – Non-Standard Experimental and Alternative OWTS Approval Process
Section 13 – Non-Standard Experimental and Alternative OWTS Standards (Size: 2.61 MB)
Section 14 – Non-Standard and/or Commercial OWTS Operational Permit and Monitoring
Section 15 – Vesting Certificates
Section 16 – Subdivisions and Lot Line Adjustment Requirements
Section 17 – Variance Requirements
Section 18 – Variance Prohibition and Special Standards Areas (Size: 3.40 MB)
Section 19 – Dispute Resolution
Section 20 – Tier 3 Treatment, Monitoring, Inspection and Sampling for Supplement Treatment Units
Section 21 – Waterless Toilets Appendix A – Experimental and Alternative OWTS
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