Modeled earthquake losses and social vulnerability in Charleston, South Carolina

This paper examines the spatial linkage between social vulnerability and estimated earthquake losses for differing levels of event magnitude. Charleston, South Carolina was selected as the sample urban setting for the study. Earthquake losses (debris generated and direct economic costs) were modeled using the HAZUS-MH software package. Social vulnerability, those characteristics of groups that increase the likelihood of losses or decrease the recovery ability, was modeled using the Social Vulnerability Index (SoVI). Modeled earthquake losses were higher in the urbanized core surrounding the Charleston peninsula and expanded outward, especially east and west of the peninsula along the coast. Physical parameters (peak ground acceleration and distance from the epicenter) were more significant in predicting impacts than social vulnerability. However, in examining the relative impact of earthquake losses accounting for wealth (dollar losses per average income as the dependent variable), we found social vulnerability is a significant predictor, suggesting that those areas with higher levels of social vulnerability experience a greater relative impact and may therefore face more obstacles in post-event recovery than areas with lower social vulnerability.