Uncertainty and Sensitivity Analysis of the HAZUS-MH Flood Model

Abstract

Estimating flood losses for hazard mitigation planning is an increasingly important aspect of flood risk management. The loss estimation process typically includes sequential analysis of the flood hazard, building characteristics, structural damage, and economic loss. However, the reliability of economic loss estimates from the modeling process is not well understood. This research applies the method of global sensitivity analysis to the HAZUS-MH flood loss estimation model. The work is guided by two research questions: what is the uncertainty of the flood loss estimates, and what is the relative contribution of each model component to the overall uncertainty? Based on the uncertainty analysis, the estimate at the upper bound of loss distribution was found to be a factor of three higher than the lower-bound estimate. The sensitivity analysis revealed the choice of digital elevation data to be the most influential modeling stage. Recommendations are provided so that HAZUS-MH users can develop more reliable flood loss estimates for both data-rich and data-poor environments.