At the Blog | February 4, 2024

Sea Level Rise and the San Francisco Bay Area: A Regional Approach to Adaptation

By Larry Goldzband

A key element of Joint Venture’s mission is to champion causes that spill over local boundaries. Nowhere is this need more literal than in the case of sea level rise.

The following post is adapted from a presentation made to the Joint Venture Board of Directors by Larry Goldzband, Executive Director of the Bay Conservation and Development Commission, on November 22, 2024.

The San Francisco Bay is the single dominating feature of the region – we don’t call ourselves the Mountain Area or the Valley Area, but the Bay Area. Sea level rise is already encroaching on the San Francisco Bay shoreline, and the trend is expected to accelerate in coming decades.

Without a strong regional plan, the impact – and the resources to address it – will be unevenly distributed across the Bay Area and the cities touching the Bay. If each jurisdiction “goes it alone,” we can anticipate maladaptation, with catastrophic consequences (unintentional flooding, loss of property, loss of habitat) and inequitable outcomes (communities most at risk having the least resources).

The Scale of the Challenge

Although the San Francisco Bay makes up one-third of California's coastline, the Bay Area will experience an estimated two-thirds of the state's sea level rise impacts. These effects won't be limited to coastal residents; people inland will also face disruptions to transportation, water supply, and wastewater treatment, along with environmental damage and economic consequences for businesses, jobs, and homes. The full impact will extend beyond the coastal region to millions of people who depend on infrastructure and critical services:

• Transportation – Every day, 5 million vehicle trips and 60,000 rail commuters traverse the Bay Area’s transportation networks, many of which are located in areas vulnerable to flooding. Additionally, many of the region's major bridges and transportation infrastructure are located along the shoreline, where flooding will disrupt commuting for people throughout the region.
• Infrastructure – Twelve wastewater treatment plants, essential for the region’s sanitation and environmental health, are situated near the shoreline due to their reliance on gravity. However, their location makes them vulnerable to damage from saltwater intrusion and rising tides. Landfills and other contaminated sites along the shoreline are also vulnerable, posing a risk of pollutants being released into the Bay and further degrading the ecosystem.
• Jobs and Housing – An estimated 104,000 jobs in the region – and 85,000 planned new jobs – could be displaced or disrupted by flooding or infrastructure loss. Additionally, 13,000 existing housing units and 70,000 planned housing units are directly threatened by sea level rise. Indirect housing impacts include rising costs for adaptation measures, as well as disruptions to transportation and infrastructure, all of which could destabilize housing markets.
• Ecosystems – The Bay Area is home to 20,000 acres of tidal wetlands, lagoons, and marsh habitats that are critical to the health of local ecosystems and wildlife. Rising sea levels will submerge many of these areas, leading to loss of biodiversity and ecological resilience. Saltwater intrusion into freshwater systems and groundwater could disrupt sensitive habitats and species that rely on freshwater environments.

The Cost of Inaction

The cost of addressing sea level rise is staggering, but the cost of inaction is even higher. The California Coastal Commission estimates the cost of sea level rise adaptation through the year 2050 at $110,000 billion. This includes:

• $52 billion – estimated for known or planned projects
• $54 billion – estimated placeholder costs for areas with adaptation needs
• $3 billion – for additional sediment management needs

By contrast, the cost of doing nothing is even more alarming. The Coastal Commission estimates the cost of inaction could surpass $230 billion, accounting for the value of assets at risk from flooding and environmental degradation.

Beyond the financial cost, the consequences of inaction will disproportionately affect low-income communities, many of which are located near the Bay shoreline. Failure to protect these areas could result in significant social upheaval and the displacement of vulnerable populations.

A Regional Approach to Adaptation

A major challenge in addressing sea level rise in the Bay Area is the fragmented approach of local jurisdictions, which can lead to poorly designed flood defenses, uneven coastline protection, and inefficient resource allocation, leaving vulnerable communities underfunded. The Bay Conservation and Development Commission (BCDC), which has been tasked with guiding the region's response, is working to create a more unified and strategic response.

As part of California SB 272, BCDC is mandated to develop regional guidelines for adapting to sea level rise. These guidelines will help local governments create subregional resiliency plans that incorporate vulnerability assessments and adaptation strategies, while also aligning with broader regional strategy. Under this framework, jurisdictions with approved plans will be prioritized for state funding to implement adaptation projects.

Areas of Focus for Adaptation Guidelines

The regional guidelines will cover several critical areas, each with the goal of ensuring a more resilient Bay Area:

• Housing and Development – Planning for strategic, safe, and climate-resilient growth to accommodate the region’s population while reducing exposure to flood risks.
• Critical Infrastructure – Protecting key infrastructure, such as transportation networks and wastewater treatment plants, ensuring they remain functional despite rising sea levels.
• Community Health – Addressing health disparities and ensuring that vulnerable populations are not displaced.
• Transportation and Transit – Preserving regional transportation routes essential to the movement of people and goods, which are critical to the Bay Area's economy.
• Public Access and Recreation – Ensuring that the public can continue to access the Bay’s shoreline for recreational and cultural purposes.
• Shoreline Contamination – Tackling the risk of increased shoreline contamination in flood-prone areas, particularly in disadvantaged communities.
• Ecosystem Health and Resilience – Protecting and enhancing the region's ecosystems, such as tidal marshes and wetlands, that provide natural flood defenses and support biodiversity.

The Road Ahead

The San Francisco Bay Area has a unique opportunity to set a global example for how cities and regions can adapt to the challenges of climate change. The development of regional guidelines and local adaptation plans is already underway, with BCDC aiming to adopt its Regional Shoreline Adaptation Plan in December 2024. Local, subregional plans are expected to be in place by January 2034.

As the Bay Area moves forward with its sea level rise adaptation efforts, it will be critical for all stakeholders – local governments, community organizations, businesses, and residents – to come together and work collaboratively to ensure that the region remains resilient in the face of this growing threat. The sooner we act, the better positioned we will be to protect our communities, our infrastructure, and our environment for generations to come.

About the Author

As Executive Director of the San Francisco Bay Conservation and Development Commission (BCDC), Larry Goldzband leads planning and policy development efforts and guides disparate stakeholders to agree on difficult policy choices. BCDC is a permanent state agency dedicated to the protection and enhancement of the San Francisco Bay and to the encouragement of responsible use of the Bay.