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SAN-003 Public Sewer General Inspection & Construction Guidelines

Version 05/11/2021


To provide general inspection information and construction guidelines for sewer permits for building sewer (from structure to property, or sewer easement, line cleanout) connections.


  1. The applicant must have an issued sewer permit. (Note that a Building Permit is not a Sewer Permit).
  2. The permit, inspection, sewer service, and connection fees must be paid in full.
  3. A copy of the issued permit, site plan, and approved plans (if any) must be available on site for County staff upon request.

Construction Standards

All work must conform to the Sonoma County Water Agency’s Design and Construction Standards for Sanitation Facilities and all materials used shall be per the Sonoma County Water Agency’s Design and Construction Standards for Sanitation Facilities, Section 9, Approved Materials List. Both the standards and materials list referenced above may be viewed online at:


  1. Approval to commence any sewer work must be granted by the Permit Sonoma Engineering Inspection Division. Start Work approval may be requested by calling the Automated Inspection Request System at (707) 565-3551 and scheduling an Inspection Item 430, a minimum of five days in advance of the proposed start work date.
  2. All sewer lines must pass an air or water pressure test per Section 8.8 of Sonoma County Water Agency’s Design  and Construction Standards for Sanitation Facilities prior to permit final. To avoid reinspection fees, we recommend the contractor perform this test once satisfactorily before calling for an inspection.
  3. For guidance on the various methods for requesting inspections, please refer to:


  1. Additional fees will be assessed for reinspections, late inspections, or work done without a permit as per the current Permit Sonma Fee Schedule.
  2. An encroachment permit is required for any work in the public right-of-way.
  3. A septic permit is required to abandon an existing septic tank. (Please see: Septic Tank Destruction Permits WLS-002).
  4.  Some site conditions, such as steep grades or shallow sewer mains, may require the use of details other than those shown below. Some examples of those details include pump systems, pressure lines, or alternate trench sections. For more information, please review the project’s site conditions with Permit Sonoma Sanitation Staff.

Construction Guidelines

Building Sewer Plan

Sewer Plan

Trench Detail

Sewer Trench Detail

Clean-out Detail

Sewer cleanout details

A = Installed pipe fitting where necessary to increase pipe size of building drain to building sewer (where two pipes of dissimilar material are to be joined, they shall be joined with a flexible rubber coupling.)

Note: These details are excerpts of SCWA Standard Drawings 122, 130, and 133, and these complete Drawings should be reviewed for additional information. The complete standards may be viewed online at:

Contact Information

Contact Us by Phone
2550 Ventura Avenue
Santa Rosa, CA 95403
38.465074, -122.723705

Sanitation Codes & Standards

Sanitation Codes and Standards
Codes set forth uniform requirements for contributors to the wastewater collection and treatment systems.