The short- and long-term risks from climate change, such as sea level rise, coastal erosion and beach loss, and ocean acidification continue to affect a vast number of people and industries in California. For additional background information and discussion of climate impacts and vulnerabilities of the Ocean and Coast Sector, visit the Background & Climate Impacts information excerpted from the Adaptation Planning Guide and explore the Topic search below.
Because of the ever-growing value of California’s coastal areas and our dependence on the coast and ocean for recreation, food, and critical infrastructure such as ports, airports, and power plants, it is important to assess how climate change will impact our ocean and coasts and how to best anticipate, plan, and prepare for these changing ocean conditions. Learn more about the actions California is taking to address sea level rise, ocean acidification, and other changes to our oceans from a changing climate through the Ocean Protection Council's climate change program. Another important resource for coastal adaptation planning is California’s Coastal Sediment Master Plan, developed in collaboration between the U.S. Army Corp of Engineers, various state agencies, and many local and regional agencies. This Master Plan includes regional sediment management plans that cover most of the state’s developed coastline as well as various technical, economic, and policy tools and studies that relate to the regional plans.
Examples of adaptation strategies are provided on the Adaptation Strategies page and can be found in many of the resources available by search below. To find resources submitted under AB 2516 and AB 184 sea level rise database requirements, search using the key word “AB 2516".
Making California’s Coast Resilient to Sea Level Rise: Principles for Aligned State Action
In early 2020 CNRA Secretary Crowfoot and CalEPA Secretary Blumenfeld convened two high-level meetings of 17 state agencies to co-develop a set of Sea Level Rise Principles. The final set of SLR Principles represent a commitment to aligning state planning, policy setting, project development, collaboration, and decision-making around sea level rise (SLR). They are intended to unify state agencies in effective, coordinated action toward climate resilience grounded in science, partnership, communication, and local support.
The SLR Principles will guide state agencies’ sea level rise initiatives with a common, clear, and foundational vision. They describe unified, effective SLR resilience action in six thematic areas: best available science, partnerships, communications, local support, alignment, and coastal resilience projects. The Principles will anchor collaboration across state agencies to effectively build California’s resilience to sea level rise.
Defining the Sector
The Ocean and Coast sector encompasses the 1,200 miles of California shoreline that include marine habitats, beaches and coastal recreation areas, ports, and bays throughout the state. Nearly 75 percent of California’s population lives in coastal cities or counties, and this sector sustains approximately 500,000 jobs and $19 billion in salaries and wages. These areas contain both diverse coastal communities and unique ocean habitat and resources. Major considerations in this sector include marine ecosystems, livelihoods and economies, public access to the coast, recreation, and the well-being and safety of coastal communities. This sector also fosters multiagency coordination between the California Coastal Commission, Department of Parks and Recreation, Ocean Protection Council, State Coastal Conservancy, State Land Commission, and the San Francisco Bay Conservation and Development Commission.
Ocean and coast areas across California are directly exposed to sea level rise, ocean acidification, and increased frequency of coastal storms. This creates vulnerabilities in both natural and human-made systems that depend on stable and healthy coastlines.
Marine ecosystems, including coastal and tidal habitats, are at risk of damage from coastal storms, changing pH levels due to ocean acidification, and increased algal blooms that cause hypoxia (the absence of oxygen), affecting coastal plants and animals. Coastal wetlands are being damaged by sea level rise and saltwater intrusion that is changing the chemical composition of the ecosystem. Sea level rise is causing coastal wetlands to migrate inland, which is difficult or impossible in areas that have been developed to the shoreline.
Coastal economies are closely tied to the health of marine ecosystems. Marine fisheries and shellfish industries are already witnessing damage to the shells of shellfish due to ocean acidification. Marine fishing economies are vulnerable to damage from increased coastal storms and harmful algal blooms. Coastal tourism is vulnerable to losses from shrinking beaches, bluff and dune erosion, and coastal flooding, which damage important park and recreational facilities.
The built environment in coastal communities is not only vulnerable to economic hardships, but to damage in infrastructure and buildings that support residents and businesses. Rising tide levels and storm events can increase the vulnerability of essential buildings and infrastructure that are commonly located on coastlines, including airports, bridges, highways, cargo and passenger rail, ports, and wastewater treatment plants. Damage to these facilities could prevent residents from evacuating during emergencies or contaminate drinking water supplies. Additionally, storm surge and high winds during coastal storms have eroded bluffs and dunes, leaving buildings and infrastructure vulnerable to damage from ground failure and slope destabilization.
Appendix C provides examples of strategies to support a more resilient ocean and coast sector as part of adaptation planning efforts. These strategies are generalized approaches that can be refined for the specific ocean and coastal programs in a community.
Sea Level Rise vs. Coastal Flooding
Sea level rise is the long-term rise of mean high tide levels along the coast, which can occur over years or decades. Coastal flooding, on the other hand, is the short-term rise in sea levels due to a coastal storm or “king tide” event. These events can create a temporary increase in sea levels of approximately 28 to 30 inches or higher depending on the size of the storm. Higher sea levels caused by sea level rise can give a boost to smaller floods that, during normal conditions, would not have been large enough to flood dry land.
|Climate hazards||Adaptation Strategy||Factors to Consider||Category||Sector overlap||Responsible Agencies||Funding||Examples & Sources|
|Ocean and Coast Sector|
|Sea level rise||Strategy OCR-1: Develop an adaptive management plan to address the long-term impacts of sea level rise. Include an assessment of local vulnerability, including infrastructure such as roads and water reclamation facilities, buildings in the inundation areas, and ecosystems. An adaptive management plan can provide for flood and erosion protection with consideration for future sea level rise, taking into account 100-year flood events when planning new development and infrastructure projects and/or reconstruction of existing projects. This plan should result in identification of areas of priority, suggested strategies, long-term indicators, and integration into other local policy documents (e.g., local hazard mitigation plans and local coastal programs).||These measures are likely to be most successful if efforts are made to coordinate sea level rise protection measures with adjacent jurisdictions to create contiguous shoreline protection. The California Coastal Commission should also be involved in this process.||Plans, Regulations, and Policy Development||Land Use and Community Development||Cities and counties California Coastal Commission||General fund LCP Local Assistance Grant||California Coastal Commission Residential Adaptation Policy Guidance City of Del Mar Sea-level Rise Adaptation Plan San Francisco Sea Level Rise Action Plan: https://sfpublicworks.org/about/san-francisco-sea-level-rise-action-plan|
|Sea level rise||Strategy OCR-2: Facilitate managed retreat from, or upgrade of, the most at-risk areas. Gradually retreat from the most at-risk areas, use these areas differently, or upgrade buildings and other facilities in at-risk areas. Develop plans allowing for coastal inundation in defined areas. Jurisdictions should assess local risk areas based on projected coastal inundation and the importance of facilities, infrastructure, or ecosystems that are at risk. Based on this assessment, top-priority areas should be identified, and actions should be taken for retreat or upgrade. Each development or infrastructure project must be assessed based on how long the action will be adequate given sea level projections.||When evaluating development or infrastructure projects, determine whether to (1) relocate them inland, (2) elevate them above projected sea level rise, or (3) leave them in place and make new or proposed facilities more flood-proof. Determine factors such as cost, environmental impacts, funding sources, timing, and compatibility with other plans. These choices should be made in close collaboration with the California Coastal Commission.||Plans, Regulations, and Policy Development||Land Use and Community Development Transportation||Cities and counties California Coastal Commission||General fund LCP Local Assistance Grant||California Coastal Commission Residential Adaptation Policy Guidance City of Del Mar Sea-level Rise Adaptation Plan San Francisco Sea Level Rise Action Plan: https://sfpublicworks.org/about/san-francisco-sea-level-rise-action-plan|
|Sea level rise||Strategy OCR-3: Require accounting of sea level rise in all applications for new development in shoreline areas. Ensure that all applications for new development account for projected sea level rise and provide adequate protection (e.g., elevation setbacks, nature-based solutions). Shoreline areas can include beaches, bluff-tops, and areas along bays or estuaries. Accounting of sea level rise in these areas requires that jurisdictions prepare projected sea level maps to estimate long-term changes in the coastline, bluff erosion rates, and projected coastal flooding. Based on these maps, appropriate setback and/or other appropriate protection can be determined. For consistency, consideration of sea level rise should be included in project review guidelines, integrated into local coastal programs, and reviewed as part of California Environmental Quality Act (CEQA) evaluation.||Collaboration among adjoining jurisdictions will foster more comprehensive shoreline protection. The implementation of this strategy will also require staff and community education about sea level rise, inherent risks, and available options for addressing the risk.||Plans, Regulations, and Policy Development Programmatic||Land Use and Community Development||Cities and counties California Coastal Commission San Francisco Bay Conservation and Development Commission (BCDC)||General fund LCP Local Assistance Grant||BCDC: https://bcdc.ca.gov/BPA/SLRfactSheet.html|
|Sea level rise||Strategy OCR-4: Preserve undeveloped and vulnerable shoreline. In shoreline areas, preserve undeveloped land to support ecosystem adaptation in areas where sea level rise may cause inland migration of species and habitat. Undeveloped shorelines areas, particularly along bays or estuaries, should be evaluated for ecological value, vulnerability, and role in local flood protection. Protection and restoration of these areas can provide flood protection and support habitat and species migration. Tools that can be used to facilitate this protection can include several that are familiar to local and regional jurisdictions, including land use designations (e.g., zoning), building setbacks, consideration during project review, easement acquisition, and habitat conservation plans in situations where special-status species are present.||Land use and tax policies should be evaluated to avoid development on restorable habitat that is critical to ensuring that ecosystems are resilient to climate change impacts. Action such as land preservation can be coordinated with local land conservation and wildlife organizations. The California Coastal Commission should also be consulted. These actions do not need to strictly prohibit development. Instead, shoreline areas should be carefully evaluated. In some cases, development can be managed to allow for future ecosystem resilience.||Plans, Regulations, and Policy Development||Land Use and Community Development Biodiversity and Habitat||Cities and counties California Coastal Commission California Coastal Conservancy||General Fund Habitat Conservation Fund grant Department of Fish and Wildlife grants Department of Water Resources grant Wildlife Conservation Board grant ESA Nontraditional Section 6 grant National Fish and Wildlife Foundation grants Other grant programs||Case Studies of Natural Shoreline Infrastructure in Coastal California San Francisco Bay Living Shorelines Project Living Shoreline Academy Save the Bay Restored Wetlands|
|Sea level rise; flooding||Strategy OCR-5: Use transfer of development rights for the rebuilding of structures damaged or destroyed due to flooding in high-risk areas. Designate areas for increased density in a community, allowing landowners in the high-risk areas to sell their development rights. Transfer of development rights (TDR) is often used to preserve agricultural lands or undeveloped areas. In this case, the same approach would be used to transfer the development rights of a high-risk property to a lower-risk property. The advantage is that the landowner in the high-risk area is compensated for the loss of development potential and a flood-prone area is set aside, decreasing flood risk for the whole community.||Often the most controversial aspect of TDR programs is selection of the receiving areas that will see an increase in development density. Community acceptance of this density increase requires that the program be accompanied by public education and outreach. Local land trusts can be valuable collaborators in developing the program, particularly restricting new development in high-risk areas. Jurisdictions should also consider the transfer of development rights for properties with historic and cultural significance.||Programmatic||Land Use and Community Development||Cities and counties California Coastal Commission||General fund|
|Ocean acidification||Strategy OCR-6: Establish early warning systems to monitor carbon chemistry at shellfish hatcheries and worked with hatchery managers to develop methods that protect developing oyster larvae from exposure to low pH waters. Ocean acidification impacts are largely not able to be mitigated by local-level action, but cities and counties can work with state and federal agencies to monitor near-shore water chemistry and develop responses to mitigate damage to fisheries. In addition, land use practices to reduce non-point source pollution can reduce overall stress on shellfisheries.||Though not widespread in California, the state does have commercial shellfisheries that are important to the local economy and coastal culture. In addition to short-term actions to preserve these fisheries, communities may need to consider the long-term loss of these fisheries and how to transition impacted families and businesses to other activities.||Programmatic||Agriculture [aquaculture]||Cities and counties California Department of Public Health California Department of Fish and Game||California Department of Public Health||Center for Ocean Solutions: https://www.oceanfdn.org/sites/default/files/Why%20Ocean%20Acidification%20Matters%20to%20California.pdf NOAA Ocean Acidification Program: https://oceanacidification.noaa.gov/Home.aspx State of Washington Department of Ecology: https://ecology.wa.gov/Water-Shorelines/Puget-Sound/Issues-problems/Acidification|