Sea Level Rise Planning

A king tide submerges a Palo Alto Baylands trail on January 12, 2024. King tides help us visualize what sea level rise might look like in the future.

The State of California anticipates that relative sea level rise stemming from greenhouse gas emissions and related climate change poses significant economic, environmental and social risks to communities along the San Francisco Bay Shoreline.

The San Francisco Bay Conservation and Development Commission (BCDC) adopted Regional Shoreline Adaptation Plan Guidelines (RSAP) in December 2024. The RSAP requires local governments along the Bay shoreline to create shoreline resiliency plans to address rising sea levels that align with RSAP requirements.  In fall 2025, Santa Clara County, in partnership with Palo Alto and neighboring cities, was awarded $2.6M in SB-1 Grant funds to develop a County-led subregional shoreline adaptation plan. The funds will be used to satisfy RSAP requirements which will include an assessment of existing conditions, a vulnerability assessment, adaptation strategies, land use and policy plans, implementation plans, public engagement, CEQA determination, a determination of the cost inaction, potential project lists and a funding strategy. Local agencies, such as the City of Palo Alto, must also approve this plan to go into effect at the local level. RSAP development will commence in early 2026 and will complement Palo Alto’s past efforts to date. The Santa Clara County RSAP project is estimated to be completed in 2029.

Related Projects 

Palo Alto Horizontal Levee Pilot Project (2025/2026)

Adjacent to Byxbee Park, this pilot project is the first horizontal levee in the Bay Area to be hydrologically connected to San Francisco Bay. Its design, permitting, funding and post-construction monitoring will inform future nature-based solutions to sea level rise around the Bay Area.

South San Francisco Bay Shoreline Feasibility Study (2024)

In partnership with Valley Water and other agencies, the United States Army Corps of Engineers completed a cost/benefit study for the “Shoreline II” reach of the San Francisco Bay Shoreline Study which includes Palo Alto’s shoreline from San Francisquito Creek to Permanente Creek in Mountain View. The study concluded “no federal interest” (insufficient cost to benefit ratio). The study is still open and USACE could conduct a feasibility study for the Shoreline II area in the future. Questions specific to the Shoreline II can be submitted using the Valley Water customer request system.

Sea Level Rise Vulnerability Assessment (2022)

The Sea Level Rise Vulnerability Assessment documents potential sea level rise and related shallow groundwater hazards to City and community assets from increments of sea level rise between 12 to 84 inches. This is representative of what may occur through the year 2100 based on estimates from the State of California Ocean Protection Council Sea Level Rise Guidance (2018).

San Francisquito Creek Downstream Project Completed (2019)

The Downstream Project was completed by the San Francisquito Creek Joint Powers Authority. The project installed floodwalls, or engineered levees and widened the downstream section of the creek. It provides protection from three feet of sea level rise to 1,700 properties.

Sea Level Rise Adaptation Policy (2018)

The Sea Level Rise Adaptation Policy outlines roles and responsibilities for the City to prepare for sea level rise and the assumptions that should be used for future sea level rise conditions.