To: Board of Supervisors
From: Warren Lai, Public Works Director/Chief Engineer
Report Title: APPROVE the San Pablo Dam Road - La Honda Road Storm Drain and Slide Repair Project and take related actions under CEQA, El Sobrante area.
☒Recommendation of the County Administrator ☐ Recommendation of Board Committee
RECOMMENDATIONS:
APPROVE the San Pablo Dam Road - La Honda Road Storm Drain and Slide Repair Project (Project) and AUTHORIZE the Public Works Director, or designee, to advertise the Project, El Sobrante area. [Project No. 0672-6U6272] DCD-CP# 23-18 (District I), and
FIND, on the basis of the whole record, including the proposed Initial Study/Mitigated Negative Declaration and any comments received and staff responses thereto, that there is no substantial evidence the Project may have significant effect on the environment, and that the Mitigated Negative Declaration (MND) reflects the independent judgment and analysis of the lead agency, Contra Costa County (County).
ADOPT the MND and Mitigation and Monitoring Reporting Program (MMRP) for the Project.
SPECIFY that the Contra Costa County Public Works Department is the custodian of the documents and other material that constitute the record of proceedings upon which the Board’s decision is based, and that the record of proceedings is located at 255 Glacier Drive, Martinez, CA.
DIRECT the Director of Department of Conservation and Development (DCD), or designee, to cause a CEQA Notice of Determination (NOD) to be filed with the County Clerk and State Clearinghouse, and
AUTHORIZE the Public Works Director, or designee, to arrange for payment of $3,043.75 for California Department of Fish and Wildlife fees, and a $50 fee to the County Clerk for filing the NOD.
FISCAL IMPACT:
Estimated Project cost: $5,679,917. (85% Federal Emergency Relief Program, 15% Local Road Funds)
BACKGROUND:
The purpose of the project is to repair a landslide along San Pablo Dam Road located approximately 200 feet southeast of the intersection with La Honda Road and to repair the damaged roadway, culvert, and other associated damages. The replacement involves the installation of a stitch pile wall on the embankment between the roadway and San Pablo Creek; the installation of a geosynthetic reinforcement and regrading of the embankment slope in an area upslope of the stitch pile wall; the relocation and replacement of a failed 18-inch corrugated metal pipe culvert and the installation of rock slope protection beneath the outfall; and the grading, vegetation removal, and tree removal necessary to facilitate project construction and equipment access. The project will also repair approximately 200 feet of damaged roadway and install approximately 380 feet of guardrail.
Initial Study and Mitigated Negative Declaration (IS/MND) Background
A CEQA Initial Study and MND was prepared indicating that, with mitigations, no significant environmental impacts would be created by the Project. The Project may affect the quality of the environment, however, the impacts would be reduced to less than significant levels with the adoption of the recommended mitigation measures as specified in the MMRP (Attachment A). Mitigation measures in the environmental areas of biological resources, cultural resources, geology/soils, and tribal cultural resources have been added as conditions of approval for the project and will be implemented to reduce project impacts to less-than-significant levels.
Tribal Cultural Resources Background
In accordance with California Public Resources Code Section 21080.3.1, a Notice of Opportunity to Request Consultation was sent on June 5, 2025, to Wilton Rancheria and the Confederated Villages of Lisjan Nation. These are the two California Native American tribes that have requested notification of proposed projects within Contra Costa County. Pursuant to Section 21080.3.1(d), there was a 30-day time period for each of the tribes to either request or decline consultation. Wilton Rancheria did not respond to the Opportunity to Request Consultation. The Confederated Villages of Lisjan Nation requested consultation. Consultation was conducted with the Confederated Villages of Lisjan Nation that discussed methods for resource investigation, identification and avoidance, mitigation, and monitoring measures for any Tribal Cultural Resources that may be potentially uncovered on the project site or area. Discussed measures were agreed upon and consultation concluded on September 25, 2025.
CEQA Public Comments
An MND for the proposed project was posted for public review on May 27, 2026. The public comment period for accepting comments on the adequacy of the environmental documents extended from May 27, 2026 to June 26, 2026. During that time three comment letters were received from the East Bay Municipal Utility District (EBMUD), West County Wastewater District (WCWD), and a private resident.
None of the comments received resulted in any changes to the MND circulated on May 27, 2026. None of the mitigations identified in the MND circulated have been revised and no new mitigations have been added. The comments from EBMUD and WCWD were construction coordination related, and coordination is ongoing between the County and these entities. Some of the comments from the private resident were CEQA related but were already addressed by mitigation measures in the MMRP. The private resident received, and staff response letter is included in Attachments B and C.
CONSEQUENCE OF NEGATIVE ACTION:
Delay in approving the project may result in a delay of design and construction, and may jeopardize funding.