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Frequently Asked Questions About Remodeling

Remodeling – General

How does this policy effect Waiver Prohibition Areas?

There are a number of communities subject to waiver prohibitions, with differing restrictions and requirements. However, none of the communities are identified as RWQCB Basin Plan Waiver Prohibition Areas (Section VII Policy on the Control of Water Quality With Respect to On-Site Waste Treatment and Disposal Practices). The following communities are identified as County Waiver Prohibition Areas:

Camp Meeker, Carmet, Rancho del Paradiso, Salmon Creek, Sereno del Mar, Jenner, Monte Rio, Happy Acres, Penngrove/South Cotati, West Petaluma, Russian River Meadows, South Wright Road Area, Thomas Larkin Woods, Westvue Meadows.

In general, Permit Sonoma shall not process any waiver requests for new construction on vacant land or to existing structures in Waiver Prohibition Areas that would result in an increase in flow (some of the Waiver Prohibition Areas address only a specific concern and are not a blanket waiver prohibition). All modifications to existing structures shall comply with the Permit Sonoma Remodel Policy. The Remodel Policy applies only to existing structures (defined as recent and continuous service previous two years) with no increase in flow. Under the Reutilization and Remodel Policies, justification for issuance of a waiver is required to meet the re-defined Class I standard for systems that service existing structures. Justification for waivers that are approved by Permit Sonoma for Major Additions and/or Rebuilds of existing structures are possible in County Waiver Prohibition Areas, provided there is no increase in the strength or volume of wastewater generated.

If I already have a building permit and I want to add to the scope of work, will I be subject to the new policy or the old policy?

The revised project will be subject to the new policy.

Example: Under the old policy the percentage of lineal footage of altered wall for a dwelling with a Class III system was 35%. A revised project is proposed to include an additional remodel subject to a B-BLD or <500 square foot addition as well. Under the old policy an office clearance was given based upon a microfilm record of a 1976 permitted septic system and the percentage of remodel was limited to 35%. Under the new policy, a findings report or field clearance would be required for this new remodel or minor addition (Class III system >20 years old).

Is Planning Clearance required for a Building Permit under this policy?

A Planning Clearance is not required for an interior remodel. However, Planning Clearance is required for all rebuilds and additions due to the fact that these rebuild and/or additions may impact required setbacks to property lines, scenic or riparian corridors.

Is the square footage measured by using the interior or exterior dimensions for new additions?

Use the interior dimensions for the determination of square footage of new additions of habitable space. Note that additions may not encroach upon potential reserve expansion area.

Are walls that are removed and replaced to accommodate an Addition counted as walls removed and replaced as a percentage of a Rebuild?

Yes. Addition(s) that result in the removal and replacement of 50% or more of the exterior lineal footage of existing walls count as a percentage of Rebuild.

How does this Policy relate to the Reutilization Policy?

The Reutilization Policy remains in effect. The Remodel Policy is intended to clarify the interpretation and implementation of the Reutilization Policy.

Remodeling – Findings Reports/Field Clearances

Are Findings Reports/Field Clearances required for Building Permit clearances for structures without plumbing and/or non-habitable space if the septic system serving the parcel is more than 20 years old?

As is currently the case, if Permit Sonoma does not have any record of the septic system on the parcel and a B-BLD permit application for a non habitable space structure is received, a Field Clearance is required to ensure that the structure (e.g. pool, storage building, garage, solar panels) does not adversely impact the primary or potential expansion area. All Well & Septic clearances for any B-BLD permit require proof of a minimum Class III system. However, if adequate septic system permit records do exist, regardless of the age of the system, a Findings Report or Field Clearance is not required for a B-BLD of non-habitable structures. The Remodel Policy for either a Findings Report or Field Clearance for systems older than 20 years applies only to B-BLD habitable space Building Permit clearances only.

What is the difference between a Findings Report and a Field Clearance?

A Field Clearance requires an inspection by the Permit Sonoma District Specialist. A Findings Report may be prepared by a qualified consultant (i.e. Registered Civil Engineer or Registered Environmental Health Specialist) from the private sector.

Field Clearances and Findings Reports both require the following:

  • 2 sets of an accurate site map and floor plans;
  • a layout diagram of the existing system;
  • evaluation of system performance (may include uncovering distribution boxes to insure that the system is functioning adequately);
  • age of system and expected life expectancy;
  • sizing of system;
  • replacement area availability;
  • inspection of all tanks and recent pumpers report (within last 5 years);
  • classification of system (code compliant, Class I or Class III).

A Field Clearance requires the submittal of an application for inspection and the payment of applicable fees. A Field Clearance is required in all cases in which there are no records of the septic system or if the septic system is subject to Code Enforcement. In addition, a Field Clearance is required for all Major Remodels and/or Rebuilds if the system is more than 20 years old.

A Findings Report must include a letter from the consultant, with a wet Stamp of Professional Registration, addressing the condition of the existing system. A Findings Report is acceptable for Minor Additions and/or Remodels if the system is greater than 20 years old and for Major Additions and/or Rebuild if the system less than 20 years old. Note: An Office Clearance is acceptable for Minor Additions and/or Remodels if the system is less than 20 years old and adequate records exist.

Cesspools or systems in a condition of failure will not be adequate to justify clearance for a building permit issuance.

How long are Field Clearances and Findings Reports valid?

Field Clearances and Findings Reports are valid for 3 years from the date of completion of the service.

Are the requirements for a Findings Report or Field Clearance the same for an Interior Remodel/Minor Addition as they are for a Rebuild/Major Addition?

No. Although a Findings Report or Field Clearance is acceptable for an Interior Remodel/Minor Addition, a Rebuild/Major Addition requires a Field Clearance with soils evaluation, a “minor” pre-perc), as a component of the Field Clearance process, to determine the Best Available System appropriate for the specific site.

Remodeling – Best Available System

What does Best Available System mean?

All installations should comply with current code requirements for new septic systems, if possible. In case where it is impossible or impractical to adequately upgrade the septic system to current code requirements, given site constraints, the most effective system shall be installed that results in reasonable progress toward improving the quality of the discharge given site conditions. In general, Best Available System means the most effective, economically achievable and state of the art technology currently in use for controlling the pollution that will result in reasonable progress toward improving the discharge to the environment given the site conditions.

There are four classifications of septic systems as follows:

  • Code compliant meets all State and County code requirements without waiver.
  • Class I meets State and County code requirements with waiver for undeveloped parcels.
  • Class I Best Available System with waiver meets County Reutilization and Remodel Policy requirements for developed parcels. A notarized Class I Conditional Statement (WLS-27) is required. If a Non-Standard System or an approved pretreatment unit is a component of a standard system, application to the County’s Operational Permit Program (OPR) is required.
  • Class III is a minimal functioning system consisting of an approved septic tank and leaching area on a developed lot. A notarized Class III Conditional Statement (WLS-29) is required.

Is there a distinction between Best Available System for a Rebuild and a Best Available System required for a Major Addition?

If the results of the Field Clearance for a Major Addition reveals that the existing in-ground system is functioning adequately, but it may not meet current requirements for depth of soil below trench bottom, the addition of an approved pretreatment system to the existing in-ground system would be allowed (Best Practical System). In the case of a Rebuild, the Best Available System is required, which, in some instances, may require replacement of an existing in-ground system with an above ground system, if warranted, rather than the simple addition of a pretreatment unit to an existing system. A Rebuild is held to a higher standard of septic system upgrade than a Major Addition.

Contact Information

Contact Well & Septic by Phone
2550 Ventura Avenue
Santa Rosa, CA 95403
38.465074, -122.723705

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Map of Well & Septic's environmental health districts within Sonoma County.