Palo Alto Flood Basin Tide Gate Structure Replacement Project
Valley Water provides flood protection to homes, businesses, schools and highways in Santa Clara County. As part of our commitment, Valley Water will design and construct a seismic retrofit and rehabilitation of the existing Palo Alto Flood Basin (PAFB) Tide Gate Structure to extend the service life of the current structure up to an estimated 20 year timeframe. A long-term tide-gate replacement structure will be developed with the United States Army Corps of Engineers (USACE) under the South San Francisco Bay Shoreline Phase II Project. The existing structure is located where the PAFB connects to the San Francisco Bay, one half mile northeast of the Byxbee Park parking lot on the Adobe Creek Loop Trail. The tide gate protects against coastal flooding and controls the downstream water levels for Matadero, Adobe and Barron creeks, which all drain to the PAFB. This project will continue to provide significant flood protection benefits to nearby homes, businesses and schools and a portion of U.S. Highway 101. Additionally, the project will continue to protect existing wildlife and habitat.
Project Background
The PAFB Tide Gate Structure was constructed in 1957. Due to its age and location in a corrosive marine environment, the tide gate structure is showing signs of deterioration, including spalled concrete and exposed reinforcement steel. Seepage was previously addressed by an emergency repair project in 2012. In 2017, Valley Water attempted minor maintenance repairs that would have extended the life of the structure. However, construction was suspended when difficulties were anticipated in dewatering the work area.
August 21, 2025 Pre-Construction Public Meeting
November 20, 2024 Public Meeting
Palo Alto Flood Basin Tide Gate Structure Seismic Retrofit and Rehabilitation Project
The project scope has been revised to include two phases. Phase 1 work will be to design and construct a seismic retrofit and rehabilitation of the existing tide gate structure to extend the service life. Phase 2 work will be to work with the United States Army Corps of Engineers for a long-term replacement tide gate structure as part of the South San Francisco Bay Shoreline Phase II Project.
Valley Water informational project presentations to the City of Palo Alto Parks and Recreation Commission
- August 24, 2021, meeting details: https://www.cityofpaloalto.org/Departments/Community-Services/Other-Services/Commissions/Parks-and-Recreation-Commission, and
- June 22, 2021, meeting details: https://www.cityofpaloalto.org/Departments/Community-Services/Other-Services/Commissions/Parks-and-Recreation-Commission.
Final CEQA Mitigated Negative Declaration (MND) (March 2021)
The final Mitigated Negative Declaration (MND) CEQA document is now available and can be found under the "Reports and Documents" tab above.
Staff Presentation at the Sept. 9 Palo Alto Sea Level Rise Public Meeting
Valley Water staff attended the City of Palo Alto's Sea Level Rise Virtual Meeting on Sept. 9, 2020, and presented on the PAFB Tide Gate Structure Replacement Project and the South San Francisco Bay Shoreline Project. A recording of the meeting can be viewed at this link.
Virtual Project Update Meeting - Summer 2020
Valley Water hosted a public meeting for the Palo Alto Flood Basin Tide Gate Structure Replacement project on Wednesday, June 24 at 5:30 P.M. The meeting included a presentation on the background of the project and information about the project team’s current design concepts.
What to expect
Onsite construction for Phase 1 work for the seismic retrofit and rehabilitation of the existing tide gate structure is anticipated to start in September 2025 and conclude by January 2026, to avoid impacts on nesting birds.
Due to the construction activities, a portion of the Adobe Creek Loop Trail will be temporarily closed for the duration of construction.
