To: The Board of Supervisors of Sonoma County
Department or Agency Name(s): Permit Sonoma
Staff Name and Phone Number: Scott Orr, Levan King Cranston (707) 565-1900
Vote Requirement: Majority
Supervisorial District(s): Fifth
Title:
Title
2:45 P.M. - Zone Change to remove the Z (ADU Exclusion) Combining District; 4008 Jobe Lane, Santa Rosa (Permit Sonoma File No. ZCE23-0012)
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Recommended Action:
Recommended action
Permit Sonoma recommends that the Board of Supervisors conduct a public hearing and adopt an Ordinance finding the proposed project exempt from the California Environmental Quality Act under CEQA Guidelines Section 15305 (minor alterations in land use limitations) and California Public Resources Code Section 21080.17 and approving a zone change to remove the Z (Accessory Dwelling Unit Exclusion) Combining District from the subject parcel at 4008 Jobe Lane, Santa Rosa; APN 035-072-026 (Permit Sonoma File No. ZCE23-0012). (Fifth District)
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Executive Summary:
The project proposes approval of a Zone Change to remove the Z (Accessory Dwelling Unit Exclusion) Combining District on a 0.50-acre parcel zoned Rural Residential (RR), located at 4008 Jobe Lane, Santa Rosa, approximately 300 feet west of the City of Santa Rosa. The parcel has an existing single-family dwelling on site. The majority of the property is gravel parking, which was converted from grassland sometime between 2019 and 2022, with the exception of a small (approximately 1,000-square foot) garden in the southwest corner of the property. The request would allow for an Accessory Dwelling Unit (ADU) to be developed on the subject property in the future.
The Planning Commission adopted Resolution No. 25-07 on August 26, 2025, which recommended your Board approve the Zone Change to remove the Z Combining District from the subject parcel.
Discussion:
The Z combining district was applied to the subject property during the implementation of the 1989 General Plan. The purpose of Sec. 26-76-005 of the Sonoma County Zoning Code (Z - Accessory Dwelling Unit Exclusion Combining District) is to provide for the exclusion of accessory dwelling units in specific areas of Sonoma County. This includes areas where there is an inadequate supply of water for drinking or firefighting, where there is inadequate sewer services or danger of groundwater contamination, where the addition of accessory dwelling units would contribute to existing traffic hazards or increase the burden on heavily impacted streets, roads or highways, and where, because of topography, access or vegetation, there is a significant fire hazard.
In 2019, the Board adopted Ordinance No. 6285, which removed the “Z” Accessory Dwelling Unit Exclusion Combining District from 1,924 specified parcels located in the LIA - Land Intensive Agriculture, LEA - Land Extensive Agriculture, and DA - Diverse Agriculture zoning districts countywide that met screening criteria related to fire hazard zones, biotic habitat, groundwater, traffic, and Land Conservation Contracts. Parcels in waiver prohibition areas were not included in the countywide legislative proposal due to the differing site-specific environmental and regulatory constraints in the various waiver prohibition areas. Parcels in waiver prohibition areas would continue to be considered on a case-by-case basis. Most waiver prohibition areas are characterized by clusters of small parcels without the ability to provide adequate setbacks for septic systems to neighboring wells.
The subject parcel did not pass the countywide Z Combining District removal screening criteria in 2019 due to characteristics of the parcel exceeding the scope of the countywide screening criteria. The subject parcel has a Base Zoning of Rural Residential (RR), is less than 10-acres in size, and is located within a Waiver Prohibition Area, therefore, the subject property did not meet the 2019 screening criteria. Parcels are placed into Waiver Prohibition Areas due to the high volume of groundwater present, and concentrations of properties with smaller lot sizes. The addition of Accessory Dwelling Units increases the usage of septic systems and therefore would heighten the risk for groundwater contamination. Staff have confirmed the subject property is connected to public sewer, and therefore the increase of wastewater generated by an ADU will not further intensify the risk of groundwater contamination. The subject parcel, 4008 Jobe Lane in Santa Rosa, is located within a Waiver Prohibition Area. Staff have reviewed the property in detail to confirm additional development on this site is appropriate. The City of Santa Rosa has confirmed this area of Sonoma County is situated in the South Wright sewer agreement area, and that the subject property is currently connected to public sewer. In addition, the City of Santa Rosa has confirmed they support the use of Accessory Dwelling Units at this location.
For the above reasons, the subject parcel does not meet the criteria for continued inclusion in the Z Accessory Dwelling Unit Exclusion District per Article 76 of the Sonoma County Code, and removal of the Z Combining District overlay is warranted.
The Planning Commission voted 5-0 on August 21, 2025, adopting Resolution No. 25-07 finding the project exempt from CEQA and recommending approval to the Board of Supervisors for the requested zone change to remove the Z Combining District. The project is categorically exempt under State CEQA Guidelines Section 15305 because removing the Z Combining District is a minor alteration in land use limitations in an area with an average slope of less than 20% that does not result in any changes in land use or density because under state law the addition of one accessory dwelling unit may not be considered to exceed the allowable density (Government Code § 65852.2(a)(8)). Adoption of the proposed ordinance is also exempt from CEQA pursuant to Public Resources Code section 21080.17, adoption of an ordinance by a city or county to implement the provisions of Government Code section 65852.2, regarding permitting of accessory dwelling units.
Strategic Plan:
Not Applicable
Racial Equity:
Was this item identified as an opportunity to apply the Racial Equity Toolkit?
No
Prior Board Actions:
N/A
Fiscal Summary
Narrative Explanation of Fiscal Impacts:
This is an at-cost project for which project costs are the responsibility of the applicant.
Narrative Explanation of Staffing Impacts (If Required):
N/A
Attachments:
Attachment 1: ZCE23-0012 Board of Supervisors Ordinance
Attachment 2: ZCE23-0012 Planning Commission Staff Report
Attachment 3: ZCE23-0012 Planning Commission Resolution No. 25-07
Attachment 4: ZCE23-0012 Site Plan
Attachment 5: ZCE23-0012 General Plan Land Use Map
Attachment 6: ZCE23-0012 Vicinity Map
Attachment 7: ZCE23-0012 Zoning Map
Attachment 8: ZCE23-0012 PowerPoint Presentation
Related Items “On File” with the Clerk of the Board:
Not Applicable