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Administrative Certificates of Compliance | Agriculture/Animals/Trees
Airport Land Use
| Application Processing | Business Permits
Dry Creek Valley Citizens Advisory Council | Housing/Residential Units | Zoning


Administrative Certificates of Compliance

Question What is an Administrative Certificate of Compliance?

An Administrative Certificate of Compliance (ACC) is a determination by the County that a parcel was created in conformance with the State and County laws in effect at the time the lot was created. It does NOT guarantee that the lot can be developed nor does it create new lots. The application is processed administratively, and, if approved, a certificate must then be recorded in order to be valid.

Question Who does the research needed for an Administrative Certificate of Compliance?

It is the applicant's responsibility to do the research and assemble necessary historical and legal documents to support each request. PRMD staff then reviews all of the documentation and verifies whether the lots were created in conformance with applicable state and County laws.

Question How is the decision to approve or deny an Administrative Certificate of Compliance made?

Requests for an Administrative Certificate of Compliance are made on a case-by-case basis based on the evidence provided, specific findings regarding the subdivision laws in effect at the time the lot was created, and subsequent activities on the parcels in question (i.e., mergers, issuance of building permits, Lot Line Adjustments, grant deeds, construction of buildings over the property boundaries, etc.).
PRMD’s determination on an Administrative Certificate of Compliance can be appealed to the Planning Commission.

Question Do parcel sizes affect the County's ability to approve Administrative Certificates of Compliance?

Yes, if there are contiguous parcels held under the same ownership. If the parcel is on sewer, it must be a minimum of 5,000 square feet. If the parcels do not meet these minimums, they may be subject to merger.

Question Do I need a Certificate of Compliance?

Typically, the County does not require Certificates of Compliance unless an application is made for an activity which might require verification of parcel status, such as a Lot Line Adjustment between two underlying parcels. A Certificate of Compliance might also be required when development is proposed and it is unclear whether the parcel is a separate legal parcel from contiguous lands held by the same owner. Most Certificate of Compliance applications are received because a title company would not guarantee title on one or more of the parcels being claimed by the owner.

Question I own two (or more) contiguous tax lots. Are they separate legal lots that I can sell or develop individually?

Separate tax lots (also known as Assessor’s parcels) are not necessarily separate legal lots. Tax boundaries are created for the benefit and use of the Tax Assessor. They can be created by a parcel being too big to be shown on one Assessor’s map page, being divided by a tax area boundary, having a different tax rate over a portion of the parcel as a result of an Agricultural Preserve Contract or other agreement affecting the assessed value of a portion of the parcel.

Question Is my parcel a legal lot?

There are many factors that go into the determination of parcel legality. Generally, a lot is considered to have been legally created if it was created after 1913 by a subdivision map or which followed the laws in effect at the time. Some lots created by deed or government patent before March 1967 are legal lots, but they may need to go through the Administrative Certificate of Compliance process for a formal determination. After March 1972, all lot creation requires County subdivision approval. Even if a lot was originally created legally, it may have been merged with adjacent lots by actions of a prior owner. Contact a licensed land surveyor for additional information on lot creation.



Question What is the Williamson Act (Agricultural Preserve)?

A program created by State law whereby the County gives the property owner a property tax break for maintaining their property in agriculture as an "agricultural preserve." An application is required to enter into a Williamson Act contract with the county. The contract period is for ten years and renews automatically each year unless the property owner requests and receives county approval to phase out, which takes ten years to complete.

Question What are the requirements for a Williamson Act contract?

For a Type I Williamson Act contract (Vineyard or Orchard), the minimum parcel size requirement is 10 acres with a minimum income requirement of $200 gross income per acre.


For a Type II Williamson Act contract (Grazing of Livestock) the minimum parcel size requirement is 40 acres with a minimum income requirement of $2,000 gross annual income and a minimum of $2.50 gross income per acre, per farm operation.


For a Type II Williamson Act Contract (Open Space) the minimum parcel size requirement is 40 acres.

Question What information is available about the of Phase Out of Substandard Parcels in Agricultural Preserves?

Information is available via the Agricultural Preserves FAQs for Phase Out of Substandard Parcels (PDF: 60 kB) document.

Question What types of farm worker housing programs are permitted?

Seasonal (180 days) and year-round farm worker housing and agricultural employee dwelling units are allowed in most Agricultural and Resources zoning districts. Certain minimum acreage and/or agricultural activities are required. Farm family dwelling units are allowed in the LIA and LEA zoning districts, provided that the parcel is under an existing Williamson Act Contract. Construction permits (including well and septic approval) are required for these housing units and a Zoning Permit is required.

Question How many horses and livestock animals can I have on my property?

It depends on your zoning district and the size of the parcel. In the Rural Residential (RR) zoning district, for example, you can have one horse or cow or 5 goats or 50 chickens for every 20,000 square feet of parcel area. In the AR (Agriculture and Residential) and agricultural zoning districts, the same limits apply to parcels of two acres or less, but there are no limits on larger parcels. For more specific information, refer to the appropriate zoning district in the Zoning Ordinance.

Question What permits are required to board or train horses?

In the agricultural zoning districts, a property owner can raise, board and train their own horses without any required permits. However, in the agricultural zoning districts, boarding of other people's horses is allowed only with approval of a Zoning Permit; but shows, group lessons, clinics and similar horse-related group activities require a Use Permit. In the AR (Agriculture and Residential) zoning district, no more than five horses can be boarded with a Zoning Permit, and a Use Permit is required for boarding or training six or more horses. Septic permit approval is required and restroom facilities that are accessible to persons with disabilities must be provided. Additionally, manure management plan must also be submitted for review and approval. Building permits are required for structures such as stables, barns and covered arenas. Grading permits and drainage review may be needed for earthwork and to address stormwater runoff.

Question How many cats and dogs can I have? What permits are needed?

The keeping of dogs and cats is primarily regulated by the Sonoma County Agricultural Commissioner, Animal Regulation Division. No permits are required to keep up to 4 dogs and/or 4 cats on a property. A commercial kennel, defined as keeping 5 or more dogs and/or cats for commercial purposes, is allowed with a Use Permit and a license from the Animal Regulation Division only in commercial and agricultural zoning districts. Keeping 5 to 10 dogs or cats for personal, non-commercial purposes, called a "pet fancier facility" is allowed in the agricultural and rural residential zoning districts with a license from the Animal Regulation Division.

Question Where can I find information about the Tree Protection Ordinance?

This ordinance can be found in Section 26-88-010(m) of the Zoning Code. A list of protected tree species can be found in the Section 26-02-140.


Airport Land Use


How is development regulated around airports for compatibility with airport operations?


The California Public Utilities Code establishes airport land use commissions in each county to provide for the orderly development of air transportation and to ensure compatible land uses around airports.


In January 2001, the Sonoma County Airport Land Use Commission adopted the “Comprehensive Airport Land Use Plan for Sonoma County (CALUP)”. The Government Code requires city and county general plans, specific plans, zoning and building regulations to be consistent with the CALUP. The Commission reviews proposed changes to city and county plans and regulations to determine if they are consistent with the CALUP. If the Commission finds any proposal to be inconsistent with the CALUP, the city or county may overrule the Commission determination by a two-thirds vote of its governing body after making specific findings that the proposal is consistent with the purposes of State laws on airport safety.


What policies and standards are applied to development to maintain compatibility with airport operations?


In Chapter 8, the Comprehensive Airport Land Use Plan for Sonoma County (CALUP) sets forth the policies and standards and the procedures for applying them to development. Following are the sections and contents of Chapter 8 :


8.2 : Requirements and geographic boundaries for referrals from the cities and County for planning and development proposals.


8.3 : Standards for the acceptability of various land uses in airport-area noise levels.


8.4 : Standards for the types and intensity of land uses allowed in the safety zones.


8.5 : Standards for the maximum height of structures allowed around airports.


8.6 : Policies for existing uses and making findings on allowed uses.


8.7 : Procedures for updating the CALUP and reviewing proposed plan amendments, development projects, and airport master plans.

Question How is the public informed about airport-related restrictions?

California law requires sellers to disclose "any fact materially affecting the value and desirability of the property". This includes disclosure when the property is either within two miles of an airport or if it is within an "airport influence area". This is the area where airport-related factors "may significantly affect land uses or necessitate restrictions on those uses as determined by an airport land use commission".


For the Cloverdale, Healdsburg, Petaluma, Sonoma Valley, and Sonoma Skypark airports, the Sonoma Commission Airport Land Use Commission has determined that the CALUP referral area boundaries represent the "airport influence areas". For the Sonoma County Airport, the Commission has determined that the "airport influence area" extends beyond the referral area and includes the surrounding areas where CALUP height limits are in effect and where airplanes using the instrument approach pattern would be expected to be lower than 1,000' above ground level. Additional information is available in the publications area of this site.


Application Processing

Question How long will it take to process my planning application?

The length of time to process an application depends on many factors, including the complexity of the project, whether there is public controversy about the project, and whether the application materials you have provided are complete. From the time that a complete submittal is received, Administrative (or staff) reviews take from 6 to 8 weeks. If a public hearing and environmental review is required, processing time takes approximately 6 months. If an Environmental Impact Report is required, processing may take one year or more. General Plan Amendments and Zone Changes generally take from 6 months to one year. Applications approved by the county will generally include conditions of approval which must be satisfied by the property owner/applicant.

Question Can you tell me if my application will be approved?

Most planning applications are “discretionary,” meaning that approval or denial involves some judgment on the part of the County decision makers. In order for a project to be approved, it must be consistent with the Zoning Ordinance and General Plan and potential environmental impacts must be addressed. For Use Permits that require a public hearing, the Board of Zoning Adjustments will listen to testimony from neighbors and others at the hearing and consider potential environmental impacts and neighborhood compatibility before making a decision on any project. All decisions by the hearing body are appealable to the Board of Supervisors.

Question As a permit applicant, what is expected of me at the public hearing? What is the procedure of the meeting?

At the public hearing, the staff planner will summarize the project and key issues, then the applicant (or appellant, in the case of an appeal) speaks on the matter. As a project applicant this is your opportunity to present your case to the decision makers. After the applicant speaks, anyone else in the audience can speak and then the applicant/appellant has the opportunity for rebuttal. The hearing is then closed. The decision making body then discusses the issue and makes their decision.

Question May I look at a planning application file?

Yes, nearly all files are public record and open for anyone to see. Go to the Receptionist, located in our public lobby area, to get a number and a sheet to hand the File Counter clerk, and the clerk will locate the file for you.

Question What steps can I take to facilitate or speed up the processing of my application?

Submitting a complete and clear application, including a thorough project description and a clear site plan, is very important. For complex projects, a Preapplication Meeting may be very helpful. Also, discussing your proposed project with your neighbors before you finalize your plans is highly recommended. After you submit your application, you should respond to requests from your project planner promptly and follow up on permit conditions and comments from County departments and other agencies.

Question What is a Use Permit?

A Use Permit (commonly known as a Conditional Use Permit) is an approval that allows a specific use of land, generally subject to specific conditions and/or limitations. A Use Permit is a discretionary approval, meaning that the County decision makers will exercise judgment in determining whether a specific proposal conforms with the codes and policies adopted by the County. Each zoning district lists specific land uses that can be allowed with a Use Permit. These land uses are generally those that are more intensive in nature and may have environmental or neighborhood impacts if not designed appropriately. The Use Permit process generally takes approximately 6-9 months at which time a public hearing is held before the Board of Zoning Adjustments (BZA). At the conclusion of the public hearing, the BZA will conditionally approve or deny the Use Permit application. Decisions of the BZA can be appealed to the Board of Supervisors. If approved, the applicant has two years to meet conditions of approval and implement the approved use.

Question If the use I propose is listed as a Permitted Use, is a planning application required?

Each zoning district lists specific land uses that are allowed as “permitted uses.”. In contrast to uses which require a Use Permit, permitted uses are generally less intensive in nature and have little or no environmental or neighborhood impacts. Most permitted uses are considered “ministerial,” meaning that they are approved or denied based on compliance with fixed measurable standards. These uses do not require a special planning application. However, building permits, grading permits, septic permits, etc. may be still be required. Some permitted uses require Zoning Permits which are either over-the-counter permits or require administrative review by an assigned project planner. Commercial and Industrial zoning districts require Design Review approval for all permitted uses.

Question Does my proposed project require a public hearing?

All General Plan Amendments and Zone Changes require public hearings before both the Planning Commission and the Board of Supervisors. Most Use Permits and Design Review applications require public hearings before the Board of Zoning Adjustments or the Design Review Committee, respectively. An Administrative Design Review approval (processed by staff with no public hearing) is often the only requirement for new commercial or industrial uses in existing buildings or for minor additions to existing commercial and industrial buildings.


Business Permits

Question Can I operate a business from my home?

A small business operated from a home is called a "home occupation" and they are permitted in most zoning districts. A Zoning Permit for a home occupation can be issued "over-the-counter." The application requires a statement describing the business, a site plan, a floor plan of the dwelling, and the owner's signature. Home occupation criteria include: no employees; no more than 8 customers or clients in one day; must be conducted entirely within the residence; and cannot occupy more than 25% of the floor area. In the AR zoning district an employee is permitted subject to approval of a Use Permit.

Question Does Sonoma County issue or require business licenses?

No business license is required to conduct a business in the unincorporated areas of the County. You will need a home occupation Zoning Permit to operate a small-scale business from your home. If you would like to establish a new business or to occupy a vacant business location in a commercial or industrial zone, you will need to obtain Design Review approval. In some cases, a Use Permit may also be required. Fictitious business names can be obtained from the Sonoma County Clerk.

Question Do I need any permits/review to change the name or operators of a business on my property?

Planning approvals such as Use Permits and Design Review approvals “run with the land” and automatically transfer to any new owner or business operator. If you are selling a property or business that operates under a County planning approval, you should provide the new buyer with a copy of that approval, including any permit conditions. A new permit is only required if you change the nature of the business. If you're changing from one home occupation to another type of home occupation, you should obtain a new Zoning Permit. If it is a commercial business change, you may need Design Review approval and perhaps a Use Permit. You should also check building and health requirements.

Question Can I store business-related trucks on my residential property?

If you have an approved home occupation, you may have no more than one truck up to one-ton size. Other commercial vehicle equipment storage is not allowed in residential zones.


Dry Creek Valley Citizens Advisory Council (DCVCAC)

Question What is the DCVCAC?

The DCVCAC is an advisory body formed by the Sonoma County Board of Supervisors. The group is chartered to act as a bridge for communication between the County and local residents and businesses, and the general public on local planning decisions affecting the Dry Creek Valley.

The DCVCAC provides a forum for public expression and for making advisory recommendations to the County of Sonoma and its Permit and Resource Management Department, Board of Zoning Adjustments, Planning Commission, and Board of Supervisors on applications for use permits, rezoning's, and general plan amendments in the Dry Creek Valley.

For further insight as to the formation of the DCVCAC and resolution designating the Dry Creek Valley territory subject to the jurisdiction of the DCVCAC, review the DCVCAC Blue Book. In addition, review DCVCAC's Policy and Procedure.


Question As a project applicant within the Dry Creek Valley, are there guidelines to assist in preparing for a hearing before the DCVCAC?

Yes, the DCVCAC addressed this question in detail and guidelines can be viewed at FAQs For Project Applicants Appearing before the DCVCAC.

Housing/Residential Units

Question How many houses can I have on my property?

The maximum number of dwellings is determined by the size of the parcel and the maximum residential density allowed by the General Plan and Zoning. For example, if your property is in an area where the General Plan and Zoning will allow a residential density of 10 acres per unit, and your property is 30 acres, you could have up to 3 dwellings. In most agricultural zones, “farm family” and agricultural employee dwellings may be allowed in addition to the dwellings allowed based on General Plan and Zoning density. “Second units,” which are allowed in some zoning districts and are limited to a maximum of 840 square feet in size, are also allowed in addition to the zoning density.

Question Can I live in a travel trailer on my property?

Sonoma County ordinances generally do not allow occupancy of a travel trailer on private property unless it is located in a mobile home park or, for limited time periods, in a recreational vehicle park. However, a travel trailer can be used while a home is under construction on the property, provided that a permit is obtained (see next question). In addition, under certain circumstances a travel trailer can be used to house an ill or convalescent relative or friend, or a caretaker for that person. See Section 26-88-010(p) of the Zoning Ordinance.

Question Can I live in a travel trailer or mobile home on my property while I build my house?

When you have a building permit for a new house, a septic system installed, and a foundation in place, you can live in a trailer or mobile home on a temporary basis. A permit is required and certain restrictions apply.

Question Can my dwelling be rebuilt if it is destroyed by fire or flood?

The zoning ordinance allows any legal dwelling unit destroyed by fire or flood to be rebuilt. However, the septic system may need to be brought into compliance with current codes and current building code requirements would be applied. Non-conforming dwellings (those built legally but which do not conform to current zoning requirements) can be rebuilt only on the original footprint (i.e. same size and location).

Question What is the difference between a Second Unit and a guest house?

Second units can have a kitchen and can be rented. A guest house cannot have a kitchen nor be rented separately from the main house. Second units cannot exceed 840 square feet, while guest houses are limited to 640 square feet in size. Second units require a Zoning Permit, while guest houses are allowed with a building permit in all residential zones.

Question Can I have a second unit on my property?

Most residential zoning districts allow one second unit unless there is a "Z" (Second Unit Exclusion) overlay zoning on the property. Your parcel must be at least 2 acres in size if a well or septic system is used. If public water and sewer are provided, the parcel must be at least 6,000 square feet. Approval of a Zoning Permit is required. See Section 26-88-060 of the Zoning Ordinance for detailed requirements.



Question What is the zoning on my property?

We maintain current parcel specific zoning for properties within our jurisdiction on our Official Zoning & Land Development Data page. This does not include properties within city boundaries.


Properties are listed in the database by Assessor's Parcel Number. This number can be found on your annual tax bill as shown below.


Secured Property Tax Bill
Tax Statement


Handouts explaining regulations pertaining to each zoning district are also available on our Zoning Code Regulations page.


If you don't have a tax bill available, we can locate the property using the street address and the owner's name. For this service, call (707) 565-1900 during planning phone hours and ask to speak with the "planner phone".

Question Is my property located in the County or a City?

You can find the answer to this question on your tax bill as shown above. If the Tax Rate Area number begins with two zeroes, the property is located within a City. If it begins with one zero it is within County jurisdiction.

If you don't have a tax bill available, we can locate the property from the street address and the owner's name. Please call (707) 565-1900 during planning phone hours and ask to speak with the "planner phone".

Question My proposed use is not listed in the zoning ordinance. How do I find out if I can do it?

Every situation is different, so you should begin by consulting PRMD staff at the Planning Cubicle in our office. Each zoning district identifies the specific land uses that are allowed, either as a “permitted use” or with a Use Permit. If your proposed use is not listed, it may not be allowed, or it may be that your proposed use is similar to one of the uses that is allowed. You may request a formal determination from PRMD on this question. To do so, you should detail the proposed request in writing and submit it to the Project Review section of PRMD. A fee may be charged for this review.

Question What is the difference between maximum density and minimum lot size?

The maximum density is the number of lots or units that can be created through subdivision or developed on a parcel. The minimum lot size is the smallest that any of the lots can be.

Question Can I get a variance to maximum residential density or for a use not allowed by the zoning?

Under state law, variances can only be granted for zoning ordinance development standards such as structural setback standards. To change residential density or type of use, a zone change (rezoning) is required, and possibly a General Plan Amendment.

Question Is my parcel buildable?

A parcel’s buildability depends upon constraints including parcel size and shape, slope, proximity to floodplain, soil suitability for foundations and septic systems, and water availability. Any structures will have to meet zoning ordinance setbacks from property lines, building code requirements for foundation and building design, health codes for water supply and sewage disposal, and fire codes.

Question What are the required building setbacks?

Building setback requirements vary depending on the zoning of your property. Call the Planner Phone at (707) 565-1900 during planning phone hours to verify zoning for a specific parcel. If the parcel is 1 acre or larger, Fire Safe Standards require a setback of 30 feet from all property lines, unless reduced by the Fire Marshal. Greater building setbacks or building envelopes may apply if required as part of a subdivision approval when the lot was created. This information is available at the PRMD office.

Question How can zoning setbacks be reduced?

Many zoning districts allow front yard setback reductions if other nearby houses are close to the street. This is called "yard averaging." In rural areas, setbacks may be reduced if unusual circumstances exist and neighbors support the proposed yard reduction and in such cases, a Zoning Permit is required. In some zoning districts, a Use Permit or Variance with a public hearing is required. Any proposed reduction in zoning setbacks should be discussed thoroughly with PRMD staff before plans are prepared.

Question Can I subdivide my land?

Many factors affect subdivision potential. Property owners should discuss their proposal with PRMD staff at the Planning Cubicle before proceeding with any subdivision plans. Subdivisions are regulated by state law as well as County regulations. If your property is eligible for a subdivision, you must submit a complete application including a “tentative” subdivision map prepared by a licensed surveyor or engineer, and pay the necessary processing fees. Proposed subdivisions must be consistent with the County’s General Plan, Zoning Code and with the state Subdivision Map Act. Adequate sewage disposal and water supply must be demonstrated. Subdivisions are subject to environmental review under the California Environmental Quality Act. A public hearing is held before the Project Review Advisory Committee (for a minor subdivision consisting of 4 or fewer lots) or the Planning Commission (major subdivisions of 5 or more lots). Property owners within 300 feet of the property to be subdivided are notified and have an opportunity to speak at the public hearing.

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Although every effort is made to provide complete and accurate information on this website, users are advised to contact appropriate PRMD staff before making project decisions. This may involve contacting more than one section within PRMD (e.g. Building, Plan Check, Zoning, Well & Septic, etc.), since each section implements specific codes or ordinances which may affect your project.
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