OneShoreline’s Planning Policy Guidance (adopted in June 2023)

• Version for web viewing
• Version for printing
• Interactive online Map of Future Conditions
• Recording and slides from Public Information and Feedback Session (May 9, 2023)
• Recording of presentation and discussion at the April 24, 2023 OneShoreline Board meeting

 

 

 

 

 

 

Why develop a Planning Policy Guidance?

San Mateo County has experienced dramatic weather extremes, from drought to severe flooding, while development along the San Francisco Bay shoreline continues to be guided by existing planning documents that have not kept pace with climate change. As new projects are intended to function for decades, they must be designed for future conditions including extreme storms, rising sea levels, and rising groundwater, and be aligned with regional resilience efforts to avoid costly retrofits later.

 

What is the Planning Policy Guidance?

OneShoreline's Planning Policy Guidance is a voluntary resource for the twelve cities (Belmont, Brisbane, Burlingame, East Palo Alto, Foster City, Menlo Park, Millbrae, Redwood City, San Bruno, San Carlos, San Mateo, and South San Francisco) within San Mateo County, as well as the County itself, that are directly impacted by the Bay. (Pacific coast planning is addressed separately by the California Coastal Commission.)

Because climate change impacts cross jurisdictional boundaries, this guidance aims to align long-term community protection across cities and serve as a model for other regions facing similar challenges. It is intended to be a standardized, yet evolving, resource for cities and the County to account for anticipated increases in flooding, sea level rise, and shallow groundwater rise in two key areas:

1. Planning documents (general and specific plans, zoning ordinances)
2. Approvals of new private development projects in areas near the Bay 

Four key characteristics define the Planning Policy Guidance:

• Voluntary, not mandatory — jurisdictions are strongly encouraged to incorporate it into their planning processes
• Actionable, not just a reference — the guidance provides template text for General and Specific Plans, Zoning Amendments, Project Review Checklist, and Standard Conditions of Approval
• Focused on new private development, not existing buildings or public infrastructure 
• Evolving, not static — the guidance will be updated as climate science advances and implementation experience accumulates

 

Background

The Planning Policy Guidance is the culmination of a multi-year effort that began in 2021, when the City of Burlingame reached out to OneShoreline for assistance with incorporating sea level rise in its zoning ordinance update. The City of South San Francisco then included a Flood Plain/Sea Level Rise Overlay in its 2022 zoning code update. OneShoreline also engaged the Cities of San Carlos and San Mateo in 2022 to account for climate change-fueled flooding, sea level rise, and groundwater rise in their General Plans. 

Drawing on lessons from these early efforts, OneShoreline developed an Administrative Draft of the Planning Policy Guidance in early 2023 that drew over 300 comments from the County, 10 cities, San Francisco Bay Conservation and Development Commission (BCDC), City/County Association of Governments of San Mateo County (C/CAG), San Francisco Estuary Institute (SFEI), and consultants. The Public Draft, released on April 19, 2023, yielded over 200 comments from 21 entities (public agencies, developers, engineers, environmental and environmental justice organizations, and private citizens) over a 30-day public comment period. The feedback was incorporated into the version of the Planning Policy Guidance you see on this page. 

 

Key Features of the Planning Policy Guidance

OneShoreline’s Bay Protection Standard, which equals the current FEMA Base Flood Elevation of San Francisco Bay at a specific location plus 6 feet, represents OneShoreline’s desired post-settlement elevation at the top of new shoreline protection infrastructure. Learn more on Page 4 of the guidance.

OneShoreline's Map of Future Conditions illustrates the Bay Protection Standard and the proposed boundaries of the Overlay Districts for sea level rise and shallow groundwater rise recommended in Chapter III of the document. Learn more on Page 14 of the guidance.