Revised OWTS Manual – August 31, 2018

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.

The previously proposed OWTS Manual dated August 31, 2018 incorporates feedback from the public and Board of Supervisors at the May 22, 2018 Board meeting and subsequent meetings with the Board of Supervisors Ad Hoc Committee. The strike outs and underlines in the August 31, 2018 version are relative to the April/May version presented to the Board of Supervisors at the May 22, 2018 meeting.

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OWTS Manual Summary

A summary of each of the sections of the revised OWTS Manual.

Full Version (PDF: 7.55 MB)

Accessible version in a single file with no strikethroughs.

Revised Sections

Alternate version divided into sections with strikethroughs.

• Overview of Revisions (PDF)
• Section 1 – no proposed revisions
• Section 2 – no proposed revisions
• Section 3 – Definitions (PDF)
• Section 4 – Criteria for All OWTS (PDF)
• Section 5 – OWTS Abatements, Abandonments and Repairs of Failing Systems (PDF)
• Section 6 – Requirements for Approval of Building Permits (PDF)
• Section 7 – Site Evaluation Methods and Investigation Requirements (PDF)
• Section 8 – no proposed revisions
• Section 9 – Criteria for Standard OWTS (PDF)
• Section 10 – no proposed revisions
• Section 11 – no proposed revisions
• Section 12 – Non-Standard Experimental and Alternative OWTS Approval Process (PDF)
• Section 13 – Non-Standard Experimental and Alternative OWTS Standards (PDF)
• Section 14 – no proposed revisions
• Section 15 – no proposed revisions
• Section 16 – no proposed revisions
• Section 17 – Variance Requirements (PDF)
• Section 18 – no proposed revisions
• Section 19 – no proposed revisions
• Section 20 – no proposed revisions
• Appendix A (PDF)