Benicia Marina Breakwater Rehabilitation Project

Scope

The Benicia Marina Breakwater consists of two steel sheet pile walls that extend from the shoreline into the deeper waters of the Carquinez Strait. Together, these structures protect the marina entrance channel from excessive sediment deposition and help maintain navigable access to the marina. The breakwater was constructed in 1977-1978 in preparation for the dredging of the Benicia Marina.

The breakwater works in conjunction with the City's regular dredging program. While periodic dredging is necessary to remove accumulated sediment from the entrance channel, the breakwater drastically reduces the rate of sedimentation and helps keep dredging requirements manageable. Without a functioning breakwater system, sediment accumulation within the channel would increase significantly to the point of becoming unmanageable.

In 2021, Prairie Engineers completed a comprehensive condition assessment of the Benicia Marina Breakwater. The assessment included above-water and underwater inspections of the sheet pile walls, concrete support structures, timber dolphins, and associated infrastructure. The overall conclusion of the assessment was that while the breakwater remains functional, several components are in poor, serious, or critical condition and require substantial repair.

Following completion of the condition assessment, the City retained GFT Inc. (formerly TranSystems) in 2021 to prepare repair plans and specifications and to secure the environmental permits and regulatory approvals necessary to perform the repair work.

The repair scope includes the following:

• Replacement of the northwest section of the breakwater wall.
• Replacement of the steel door at the tidal gate and cleaning/epoxy-coat of tide gate frame.
• Repair and replacement of select vertical and battered concrete piles, sheet pile walls, and timber dolphin piles.
• Repair of steel channel and concrete pile caps, replacement of portions of steel wale and associated hardware.
• Replacement of signage. 

Contract Approval Date by Benicia City Council

June 23, 2026

Tentative Project Schedule

The work began on September 21, 2026 and is anticipated to be completed in early 2027.

Construction Cost

$3,544,895.70

Funding Source

Marina Fund, Commitment for Capital / Maintenance Projects

Contractor

Power Engineering Construction Company

Construction Hours

Monday - Friday: 7:00 AM - 5:00 PM

Potential Resident Impact

Increase in ambient noise level during construction periods. Impact to marina users including reduced channel width and potential channel use restrictions for vessels with deep drafts during construction. Expect reduced channel width and depth while construction barges are in place. Check tides before departing: Martinez Tide Station Real Time Water Levels.

Project Contact

Derek Linsley
City of Benicia
Senior Civil Engineer
dlinsley@ci.benicia.ca.us

Updates

A project briefing was held at the Benicia Yacht Club on September 9, 2026. The meeting was open to the public. The presentation slides from this briefing can be downloaded below.