Hurricane Damage Assessment for Residential Coastal Structures

Abstract

Tropical storms and hurricanes are some of the costliest natural disasters in the United States. Post-Katrina damage assessment revealed $200 billion worth of damage in Florida, Louisiana, Alabama, and Mississippi. Dozens of bridges and thousands of residential structures were damaged as a result of Hurricane Katrina. Florida is one of the most storm-prone states in the United States, which experienced several hurricanes such as Andrew, George, Earl, Opal, and Ivan in the last twenty years. The tremendous population growth in Florida and other coastal states has increased the volume of residential construction along coastline enhancing the possibility of more storm damage to those structures. After a storm is over, DEP and local government personnel inspect and identify the amount of structural damage to a particular structure, and follow FEMA’s “50% Substantial Damage Rule” to determine whether the structure to be rebuilt or repaired. This process requires substantial amount of personnel time and effort, often delaying the permitting process and insurance claims. Currently, there is no efficient decision matrix to quickly assess damaged structures after a storm, and to categorize them as “repairable” and “rebuildable” for convenience. In this study, decision matrices were developed based on the current construction cost data, identified damage levels, factors affecting decision-making and current state requirements. A decision-making spreadsheet was also developed, which can be used in the storm damaged areas to quickly categorize structures for repairability or rebuildability and to provide approximate repair costs. The spreadsheet can be used in other coastal states after minor modifications.