An Exploratory Model To Characterize The Vulnerability Of Coastal Buildings To Storm Surge Flooding In Miami-Dade County, Florida

Miami-Dade County is highly susceptible to storm surge flooding. The current Federal Insurance Rate Map (FIRM), used to determine flood insurance rates for buildings, is an excellent resource yet lacks attributes that could provide a finer-resolution of actual vulnerability for building level characteristics from one parcel to the next within the same flood zone. This study developed a novel Storm Surge Building Vulnerability (SSBV) model to provide initial protocols for developing storm surge vulnerability county maps. The model was tested on transversal sections of 1254 buildings selected from Miami Beach, East Little Havana, and Sweetwater. Buildings in the county were determined to be moderately vulnerable to storm surge flooding. High-rises, masonry buildings, and buildings whose first habitable space is elevated above the ground constitute the majority of low and very low vulnerability buildings, but 97% of high and very high vulnerability buildings are between 0 and 2 story tall and three-quarters of these have slab-on-grade finished floor elevation. Our model exposes limitations of FIRM designated hazard zones: buildings within the same zone exhibit different vulnerability characteristics. This indicates the importance of creating initial protocols to consider upgrading flood insurance rate requirement from zonal categories to individual building level.