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2021 Multijurisdictional Local Hazard Mitigation Plan Table 13-2. Distribution of Population Exposed to Sea-Level Rise Hazard by SoVI Rating SoVI Rating Population Living in Exposed Areas Having the SoVI Rating Shown Number of People % of Total Exposed Population Very High 18,425 13.56% Relatively High 40,980 30.17% Relatively Moderate 43,456 31.99% Relatively Low 25,653 18.88% Very Low 7,336 5.4% 13.4.2 Property Losses associated with sea-level rise were estimated based on estimated depth of sea-level rise inundation using the depth-damage functions in the Hazus flood model. Mean depths of inundation for all structures exposed to sea-level rise were determined via geospatial analysis. The results are shown in Table 13-3. The average depth above the lowest floor is 5 feet. Table 13-3. Mean Depths of Flooding for Sea-Level Rise Scenarios Mean Depth Range of Values San Francisco Bay coast (ART data—108 inches sea-level rise) 7.37 feet 0 – 15.49 feet Pacific Ocean coast (OCOF coastal data—6.6 ft sea-level rise with 100-yr storm) 2.18 feet 0.03 – 5.41 feet Based on this average, generic damage curves were averaged by structure type to estimate a percent damage for structures and for contents. The values determined were 39.4 percent and 23.4 percent, respectively. These percent damage curves were then applied to the exposed values for structure and contents, to estimate loss. Table 13-4 shows the resulting loss estimates for the mapped sea level rise inundation zones. Table 13-4. Loss Estimation for Sea-Level Rise Buildings Impacteda 34,385 Structure Value Damaged $11,771,707,703 Content Value Damaged $5,973,743,995 Total Value Damaged $17,745,451,699 Damage as % of Total Value 9.25% a. “Impacted “ means water over the 1st floor of the structure 13.4.3 Critical Facilities At this time, all critical facilities identified as exposed to the sea level rise hazard are considered vulnerable until more information becomes available. A more in-depth analysis should be done of the mitigation measures taken by the 157 critical facilities exposed to sea level rise to determine if they could withstand impacts of inundation. 13.4.4 Environment Even a small increase in sea levels can have devastating effects on coastal habitats. It can cause destructive erosion, wetland flooding, aquifer and agricultural soil contamination with salt, and lost habitat for fish, birds, and plants. The sections below describe key environmental impacts associated with sea level rise. 13-8