Traffic Impact Fees/Area of Benefit

Area of Benefit (AOB) Program Updates

The County has a total of 15 Area of Benefit programs within unincorporated Contra Costa County. The Contra Costa County Public Works Department will be updating all of the AOB programs within the next few years. Please follow the following links to view current AOB documents, recent meeting materials and stay up to date on each AOB update. 


What is an Area of Benefit?

An AOB is a development traffic mitigation fee program designed to improve the capacity and safety of the arterial road network within a defined boundary area as development occurs. The AOB fee programs are supported by County ordinances which are adopted by the County Board of Supervisors. Money collected within a given AOB will be used to fund road improvement projects that mitigate traffic impacts generated by new development projects.

Who pays Area of Benefit fees?

Anyone who develops property and adds additional vehicle trips to the road network is subject to AOB fees. This includes, but is not limited to property owners, residential developers, commercial developers, and industrial developers.

What are some of the possible fee categories?

  • Single Family Residential
  • Multi Family Residential
  • Office
  • Industrial
  • Light Industrial
  • Commercial
  • Other Uses (As determined per Peak Hour Trip generation)

What are Area of Benefit Funds used for?

AOB Funds are used to fund projects that improve the capacity and safety of the existing roadway network. AOB funds will be used to fund projects that are listed on the AOB project list. AOB project lists are available at the Contra Costa County Public Works Department.

How are Area of Benefit fees determined?

AOB fees are determined based upon the relationship between the total estimated cost to construct road improvement projects on the AOB project list and development potential projections within the AOB boundary.

When and how are Area of Benefit Fee rates adjusted?

Fees are adjusted periodically to reflect changes in development potential and traffic needs. Fees are also subject to change annually based on changes in the applicable construction costs index.

How do I find out how much my Area of Benefit fees will be for my project?

AOB fees are calculated during the plan check phase of your project. If you would like an AOB fee estimate earlier, you may contact the AOB Program Manager at the Contra Costa County Public Works Department at 925-313-2000.

When are Area of Benefit fee waivers granted?

AOB fee waivers are granted only when vehicle trips are not added to the road network as a result of the proposed development. (e.g. replacing an existing single family home, with a new single family home)

When are Area of Benefit fee credits granted?

AOB fee credits are granted when the preexisting use is replaced by a new use that generates more traffic. The applicant would receive credit for traffic generated by the preexisting use. A project that changes a single family home into a commercial/retail building, or modifies a light industrial building into a commercial/retail building are examples of projects that would receive fee credit.

If I think I'm eligible for an Area of Benefit fee waiver or credit, who do I contact?

Contact the AOB program manager at the Contra Costa County Public Works Department at 925-313-2000.

When and how are Area of Benefit fees collected?

Fees are collected through the Conservation and Development Department, Building Inspection Division prior to the issuance of the building permit.

Where can I find the current Area of Benefit Fee Schedule?

Follow this link: Traffic Fee Schedule (PDF)

What is the basis of the Area of Benefit Program?

  1. California Government Code Section 66000-66025 (Mitigation Fee Act)
  2. California Government Code Section 66484 (Subdivision Map Act)
  3. Title 9 Division 913 of the Contra Costa County Ordinance Code

Who do I contact for more information on Area of Benefit Fees?

Email Jeff Valeros, AOB Program Manager, or call Jeff at 925-313-2031.