Resilient Infrastructure​

Enhance services to the community by investing in County facilities and infrastructure; including roads, buildings, communications, and flood protection.

Goal 3, Objective 4

Identify and retrofit bridges in County that are at high risk for damage during earthquakes.
On Track 35%

Updated: January 2024

Summary of objective implementation status (achievements or progress over last year; significant delays or issues, etc.)

Bridge projects are different from standard road construction projects as longer lead times are required for design, environmental permitting, and acquisition of right-of-way. In addition, our local communities are much more engaged and feel greater ownership of proposed bridge projects. SPI recognizes and supports this engagement through community outreach and public hearings. The result is the typical timeframe for completion of a bridge project is a minimum of 7 years and can take as long as 20 years.

SPI has 16 active bridge replacement or retrofit projects, nine of which will include seismic improvements. The nine seismic retrofit projects are:

Boyes Blvd – Bridge replacement project completed February 4, 2022

Little Wohler – Bridge replacement project  completed December 2022

Big Sulphur – Planned construction in 2024

Big Wohler – Planned construction in 2024

Chalk Hill – Design Phase

Lambert – Feasibility / Preliminary Design Phase

Monte Rio – Advanced from design phase to right of way phase with revised scope

Pena – Preliminary Design Phase

Watmaugh – Advanced from design phase to right of way phase

Our department has completed construction on two of the nine bridges needing seismic upgrades and has advanced four from the preliminary design/environmental phase to the right of way phase. SPI is planning on moving the two bridges currently in right of way phase into the construction phase as soon as 2024, pending successful r/w acquisition. SPI is committed to delivering the remaining five bridge projects in the next 5-10 years, as they are currently in the preliminary design phase. This staggered approach allows our bridge program to deliver the projects listed above and take add new bridges as current projects are completed and new funding is secured.

Key Milestone Update

  • Completed 2 projects: Boyes Blvd and Little Wohler
  • Advanced to r/w phase on two projects: Watmaugh andMonte Rio an
  • Advance to construction phase two projects: Big Sulphur and Big Wohler

Coordination and Partnership Update

SPI routinely coordinates with neighboring cities on construction projects as needed. SPI will partner with community groups as the opportunities arise.

Community, equity and climate update

These projects fall in all areas of unincorporated Sonoma County, ensuring that residents have geographically equitable services. SPI pursues and leverages federal funding for all bridge projects. Contracting includes Disadvantaged Business Enterprise (DBE) goals to encourage participation of small, minority and women owned businesses.

Public engagement plays an important role in our bridge projects. During the preliminary engineering and design phase, we host numerous public meetings to seek community input on a variety of design factors. Advance public notification to the nearby community is issued in both English and Spanish languages. We accept all forms of communication to ensure we receive full and equitable input.

As the next two projects progress to the construction phase, anticipated in 2024, outreach efforts will continue.

Funding narrative (If this objective received Strategic Plan funding in year 1 or year 2, please provide a status of expenditures to date.)

Due to the high cost of bridge projects (typically between $8M – $20M), SPI secures grant funding through the Federal Highway Administration (FHWA) before proceeding with design and construction of bridge projects. FHWA has several funding programs that allow SPI to pursue bridge retrofit and replacement projects with local match requirements of between zero and 11.47%. These programs are administered through CalTrans and eligible costs include design, environmental permitting (except CEQA), right of way acquisition, and construction. The County uses traditional Roads funding sources including allocations from State Highway Users Tax Account (HUTA) and Road Maintenance and Rehabilitation Act (SB1) to satisfy the local match requirement.