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Septic Permitting Updates Messages

Published: December 31, 2019

Key Changes to Septic Permitting

  1. Septic permit applications: Permit Sonoma now offers two main types of Onsite Wastewater Treatment System (OWTS) Applications – OTWS Construction Applications and OWTS Design Applications. The form for these applications has been updated to comply with the new OWTS Manual, and to provide more clarity for applicants on what is required for a complete application.
    1. OWTS Construction Applications are for constructing a septic system through a permit or vesting certificate.
    2. OWTS Design Applications are to demonstrate a potential septic system type and location, but not for construction.
  2. Form requirements for non-standard septic systems: Property owners submitting OWTS Construction Applications for non-standard septic systems will use a new Operational Permit Easement form, which eliminates the need for applicants to submit a notarized OPR Easement Deed and Agreement form and a notarized OPR Permit Conditions Agreement. Additionally, property owners submitting OWTS Construction Applications for non-standard septic systems will be required to provide a new form acknowledging their obligations and responsibilities mandated by the Operational Permit (OPR) program which apply to non-standard septic systems.
  3. Building permits & septic reviews: All building permit applications will be reviewed for compliance with the new OWTS Manual. Applications must meet the following requirements, among others as outlined in the OWTS Manual:
    1. No structures can be erected on a lot where the structure impairs the usefulness of the 100 percent septic reserve replacement area.
      1. Building permits for structures proposed in areas of undeveloped land must clearly show and identify a code compliant reserve replacement area on the building site plans.
      2. Building permits for structures proposed in areas of developed land with footprints that do not exceed the existing developed land area are not required to show a code compliant reserve replacement area on the building site plans; this includes interior remodels, rebuilding a structure entirely within an existing footprint, vertical or lateral construction that does not require support from undeveloped land (such as second stories or cantilevered decks), or construction on developed land (such as enclosing a carport or building a structure in an existing paved area).
    2. A site cannot be developed beyond its capacity to properly absorb sewage effluent.

Please read the more detailed description of septic permitting changes below for additional information.

More Information

Permit Sonoma is implementing a variety of septic permitting improvements in an effort to assist customers comply with the recently adopted OWTS Manual version 7.0 and to make our permitting processes clearer and more efficient.  Permit Sonoma is also providing guidance information to customers regarding these changes to better identify certain requirements and expectations. Customers are hereby advised of the following updates to Permit Sonoma’s septic permitting processes which are effective January 1, 2020:

  1. OWTS Application Types Available.  Permit Sonoma offers two main types of OWTS Applications: OWTS Construction Applications and OWTS Design Applications.  OWTS Construction Applications are applications submitted with the intent to construct a septic system through a permit or vesting certificate. OWTS Design Applications are applications submitted with the intent of demonstrating a potential septic system type and location but not for construction.
  2. OWTS Application Required Contents. Permit Sonoma has revised the required application contents for OWTS Applications (also known as form WLS-008). The update was made to comply with the OWTS Manual version 7.0 requirements for OWTS Application types as well as to more clearly identify what constitutes a complete application for a given OWTS Application type and what information must be shown within the documents required to be submitted for each OWTS Application type. In accordance with Section 4.9.B of OWTS Manual version 7.0, site plans are required to be submitted with all OWTS Applications. In accordance with Section 4.9.A of OWTS Manual version 7.0, OWTS design reports are required to be submitted with all OWTS Applications for new and replacement OWTS for complete septic systems. OWTS design reports are a new document requirement intended to consolidate the design information needed to support and prepare OWTS site plans. OWTS design reports are documents separate from the OWTS site plans. This change has been implemented in an effort to improve the application review process by having standardized and consistent document requirements.
  3. Non-Standard OWTS Application Acknowledgement form. Property owners submitting OWTS Construction Applications for non-standard septic systems will be required to provide a new form acknowledging their obligations and responsibilities mandated by the Operational Permit (OPR) program which apply to non-standard septic systems. This new acknowledgment form (also known as form WLS-0043) replaces the previous practice of requiring an OPR application, a notarized OPR Easement Deed and Agreement form, and a notarized OPR Permit Conditions Agreement. This change has been implemented to streamline the application process while still ensuring property owners are aware of their OPR obligations and responsibilities that come with a non-standard septic system. An OPR application with required documentation will still be required prior to final approval of a non-standard OWTS permit. Hard copies of this new form are available at the Well and Septic Customer Service cubicle located within Permit Sonoma.
  4. Operational Permit (OPR) application requirements update. Previously, OPR applications required the submission of two notarized documents: an OPR Easement Deed and Agreement and an OPR Permit Conditions Agreement. Permit Sonoma has merged the two previously required documents into one new Operational Permit Easement document (PDF) which contains consolidated and updated language derived from the two older documents. This change has been implemented to create an updated document acceptable to the Recorder’s Office standards, to be more efficient by consolidating two document requirements into one, and to provide clearer information to current and future property owners regarding their OPR obligations and responsibilities that come with ownership of a non-standard septic system. Prior to final approval of non-standard OWTS permit, property owners will be required to submit an OPR application with the new Operational Permit Easement document. All OPR applications previously submitted with the two older documents will no longer be accepted; Permit Sonoma apologies for any inconvenience this may cause our customers. Hard copies of this new form are available at the Well and Septic Customer Service cubicle located within Permit Sonoma.
  5. Septic reviews on Building permit applications. Building permit applications are reviewed for septic approval in compliance with the OWTS Manual version 7.0 and with the California Plumbing Code, Appendix H, Sections H 101.6 (which requires no structure be erected on a lot where the structure impairs the usefulness of the 100 percent expansion area) and Section H 101.7 (which requires that a site cannot be developed beyond its capacity to properly absorb sewage effluent). Building permits for structures proposed in areas of undeveloped land must clearly show and identify a code compliant reserve replacement on the building site plans. Building permits for structures proposed in areas of developed land with footprints that do not exceed the existing developed land area are not required to show a code compliant reserve replacement on the building site plans; this includes interior remodels, rebuilding a structure entirely within an existing footprint, vertical or lateral construction that does not require support from undeveloped land (such as second stories or cantilevered decks), or construction on developed land (such as enclosing a carport or building a structure in an existing paved area). Customers needing to demonstrate code compliant reserve replacement areas must comply with the OWTS Manual Section 4.11.A requirements. This update supersedes the last update published on August 16, 2019.