The Draft Sea-Level Rise Vulnerability Assessment identifies the areas of the City that are projected to be affected by sea-level rise and related hazards through the year 2100 without any intervention. The Vulnerability Assessment will inform the development of a local Sea-Level Rise Adaptation Plan that will evaluate various adaptation strategies to reduce coastal vulnerabilities associated with sea level rise. These plans are part of a program funded by the California Coastal Commission and California Coastal Conservancy to assist local governments in meeting new State requirements addressing sea-level rise.
The complete Draft Sea-Level Rise Vulnerability Assessment can be downloaded here.
Hard copies of the document will be available for review at:
The rate of sea-level rise in the Santa Barbara region is expected to accelerate significantly in upcoming years. The Vulnerability Assessment evaluated hazards for three sea-level rise scenarios: 0.8 feet by 2030, 2.5 feet by 2060, and 6.6 feet by 2100. The 2018 State of California Sea-Level Rise Guidance prepared by the Ocean Protection Council (OPC) is currently the best available information on sea-level rise projections in the state and recommends using these conservative scenarios when planning for structures, infrastructure, and other development that is not easily moved. For more information on sea-level rise projections click here.
The following maps provide projections of areas that could be affected by sea level rise at 0.8 feet of sea-level rise (± 2030), 2.5 feet of sea-level rise (± 2060), and 6.6 feet of sea-level rise (± 2100) without any action or intervention as analyzed in the Draft Sea-Level Rise Vulnerability Assessment. The hazard areas shown are ONLY those that could be impacted or intensified by sea level rise and are limited to bluff and beach erosion, non-storm tidal inundation, storm waves, and storm flooding. There may be other impacts of sea level rise, such as seawater intrusion, which are not mapped below. Additionally, other hazards unrelated to sea level rise exist in the City which are not shown on the maps below. Additional information on other existing hazards in the City can be found here.
FEMA Flood Maps, which can be viewed here, show existing flood hazard areas in the City from heavy rainfall and high ocean levels during extreme storms. The maps below only show those areas where flooding during extreme storms will be intensified due to sea-level rise and do not show all of the areas of the City that currently flood during extreme rainfall events.
The following maps display hazard types based on the hierarchy of hazard types and impact classes as further described in the Draft Sea-Level Rise Vulnerability Assessment. Areas may be subject to multiple hazard types, but only the most permanent hazard type for a particular area is displayed on these maps. To view the full extent and evolution over time (i.e. existing, 2060 and 2100) of individual hazard types refer to figures provided in Appendix E of the Draft Sea-Level Rise Vulnerability Assessment.
Source: USGS, ESA
Source: USGS, ESA
Source: USGS, ESA
For further information on the definition of terms related to coastal hazards (tidal inundation, storm flooding, etc.) please click here.
Although Santa Barbara has experienced a relatively small amount of sea-level rise to date, the rate of sea level rise in the region is expected to accelerate significantly in coming decades. Rising sea levels will result in increased hazards, including shoreline erosion and flooding.
The following are physical effects of sea-level rise on the City that are projected to occur without any adaptation:
Impacts are projected to be mostly limited to the area seaward of Cabrillo Blvd through 2.5 ft. of sea-level rise (± 2060). By 6.6 ft. of sea-level rise (± 2100), however, flooding from regular high tides and coastal storms is expected to extend north of Cabrillo Blvd to Highway 101. Low lying areas north of Highway 101 that currently flood during extreme storms will see a higher frequency of flooding during storms.
By 2.5 ft. of sea-level rise most of the sandy beaches in the City's westerly coastal bluff areas are likely to be lost from beach erosion. By 6.6 ft. of sea-level rise, all of the sandy beaches in the westerly coastal bluff areas and approximately half of the sandy beaches in the low lying Waterfront area could be lost.
Coastal bluff erosion rates could increase by 40% by 2.5 ft. of sea-level rise and 140% by 6.6 ft. of sea-level rise. The increased erosion rates would threaten bluff top infrastructure, private development, and public development. By 6.6 feet of sea-level rise erosion could extend to Shoreline Drive, Cliff Drive, and other bluff top streets at several locations.
By 2.5 ft. of sea-level rise portions of the wastewater system could be affected by tidal inundation and storm flooding. By 6.6 ft. of sea-level rise El Estero Water Resource Center is likely to be permanently inoperable as currently designed. This would impact wastewater service for the City's entire service area, including service to inland residential and commercial areas. Most major streets in the coastal area are not likely to be significantly impacted by 2.5 ft. of sea-level rise. However, by 6.6 ft. of sea-level rise, portions of Cabrillo Blvd, Shoreline Drive, Cliff Drive, and Highway 101 could be impacted by erosion, tidal inundation, or storm flooding.
By 2.5 ft. of sea-level rise the effects of sea level rise could impede some harbor functions and storm waves would likely significantly impact Stearns Wharf. By 6.6 ft. of sea-level rise the Harbor is expected to be unusable without major reconstruction.
After finalization of the Sea-Level Rise Vulnerability Assessment, the next step is to develop an Adaptation Plan that will address the effects of sea-level rise over time. The Adaptation Plan will analyze the feasibility, effectiveness, economic and fiscal impacts, environmental consequences, and other costs and benefits of various adaptation strategies. Three general categories of adaptation strategies will be evaluated: 1) protection of development in place through measures such as seawalls, groins, tide gates, and beach nourishment; 2) accommodation of development in place through measures such as elevation or modifications of structures; and 3) retreat through measures such as relocation of structures and development limitations.