This indicator measures the number of people expected to be living in flood zones in 2100, due to sea level rise and a 100-year flood event. For more information, see: The California Department of Public Health’s California Building Resilience Against Climate Effects (CalBRACE) Sea Level Rise Narrative.

We should all be able to live in homes and neighborhoods that are safe from sea level rise and flooding. Sea level rise can cause drowning, collisions, injuries, electrocutions, hypothermia, stress and other mental health conditions, food insecurity, unsafe drinking water, toxic releases, respiratory ailments, and displacement. Sea levels in California have already risen by 7 inches during the 20th century.¹⁴⁵ Scientists expect this trend to speed up, with seas expected to rise 40-55 inches by 2100, assuming medium to high greenhouse gas emission levels.¹⁴⁶ The impacts of rising seas are exacerbated during naturally occurring storms, flooding and tides, which can combine to flood coastal areas and nearby bodies of water. Flooded or overwhelmed wastewater treatment systems and toxic facilities can contaminate drinking water, causing gastrointestinal illness and other diseases. Flooded buildings may become moldy, increasing inhabitants’ risk for respiratory ailments. Over the long term, sea level rise can threaten protective wetlands and displace residents, potentially severing community ties and employment opportunities, and causing trauma and mental health conditions. The impacts of sea level rise are concentrated among low-income communities and communities of color, people with access and functional needs, elderly people, and people who are linguistically isolated.¹³⁶

Addressing the health impacts of Sea Level Rise requires a range of measures designed to prepare communities and households for changing coastlines and flooding and to increase resilience.⁶⁹

Plan for Resilience

Assess Vulnerabilities

Legislation enacted in 2015 (SB 379) requires California jurisdictions to conduct vulnerability assessments and define resiliency goals, policies, and objectives in either the safety element of their general plan, or by incorporating it in local hazard mitigation planning. Local jurisdictions can reduce the health impacts of extreme heat by using these planning processes to understand likely climate changes and impacts, assess vulnerability, and craft interventions. The State of California has developed the Adaptation Planning Guide, a step-by-step guide for local governments, and the U.S Centers for Disease Control and Prevention’s Building Resilience Against Climate Effects (BRACE) Framework offers guidance for health agencies and others seeking to address the health effects of climate change.

Assessing vulnerability to climate impacts is a particularly important step in resilience planning. While climate change impacts all Californians, some individuals and families are more impacted, and have fewer resources to draw upon to help them adapt. The health impacts of climate change often deepen existing social inequities—magnifying or layering new risks on top of economic, social, environmental, biological, and health disparities. Using the BRACE framework, the California Department of Public Health has produced Climate Change and Health Profile Reports, summarizing health risks and vulnerability by county. They have also published Climate Change and Health Vulnerability Indicators to help local jurisdictions understand climate change and health vulnerability. The Healthy Places Index can also be used to assess underlying social vulnerabilities at the census tract level.

Maximize Health Benefits

Actions designed to improve climate resilience also provide the opportunity to maximize additional health or quality of life benefits that can be achieved in addition to increased resilience. Sea level rise adaptation measures create several opportunities for additional benefits. For instance, green infrastructure and “soft” defense initiatives can help reduce heat-island effects, create opportunities for healthy transportation and recreation and offer targeted job opportunities for communities with high rates of unemployment; managed retreat offers opportunities for smart growth planning and enhanced walking, biking and transit connections; infrastructure upgrades (like resilient drinking water systems) can help ensure access to safe drinking water in the face of other climate events and emergencies; and planning for sea level rise can help build community capacity to engage in other planning efforts. Local governments should prioritize interventions that minimize risk in low-income communities or communities of color, while maximizing benefits that support healthier community conditions.

Ensure Participation

Resilience efforts should prioritize the participation of community members in each step of the process. This will help ensure that community standards, expectations and requirements are effectively addressed, while building buy-in and support for resilience measures, and improving community capacity to envision and address climate impacts. For more information, see: The California Department of Public Health’s Climate Action for Health, and the Urban Sustainability Directors Network’s Equitable, Community Driven Climate Preparedness Planning.

Policy Actions

Local governments have many tools they can use to increase resilience to sea level rise. In the short term, they should make sure they are Getting Ready, by reviewing and improving emergency response plans and systems to warn and protect residents during flooding events. When floods occur, effective and targeted Emergency Response systems should be in place. Jurisdictions can also help their residents become Flood Resilient Households who are able to bounce back following flooding.

In the longer term, governments can pursue Managed Retreat to move development out of the flood plain and Smart Growth to use land more efficiently. They can also invest in Shoreline Protection to defend households, development, infrastructure and recreation areas from rising seas and storms, and in Green Communities to increase water absorption and reduce flooding and storm water surges. They can also help foster Community Power and Connection which has been shown to reduce social vulnerability and the health impacts of climate events.

Although climate resilience actions tend to save money in the long term, some come with a high immediate cost. Several funding sources and technical assistance programs can support local government efforts to improve resilience. For more information, see: The U.S. Climate Resilience Toolkit’s Funding Opportunities Page, and the Federal Emergency Management Agency‘s Hazard Mitigation Assistance.