Authors: Supath Dhital, Anupal Burauh, Parvaneh Nikrou, Sagy Cohen – The University of Alabama, Tuscaloosa
Presentation Type: Poster
Title: A Detailed Comparison between OWP HAND-FIM and HEC-RAS Predictions
Abstract: This study presents the comparative analysis of flood inundation extent and depth predictions by the Office of Water Prediction Height Above Nearest Drainage (OWP HAND-FIM) and HEC-RAS for a range of return periods (2, 10, 25, and 50 years) in one case study. Flood mapping assessment is crucial for effective flood risk management and decision-making. By focusing on just two models, this study offers insights into OWP HAND-FIM performance compared to a traditional hydraulic model. The range of flood magnitude and the depth of the analysis offer a more nuanced understanding of the implications of simplified FIM predictions by the OWP HAND-FIM approach. Our results show that overestimation by the OWP HAND-FIM model decreases with an increasing year return period (e.g. from over 23% for 2 years tos 6.71% at 50 years). The inundation extent predicted by OWP HAND-FIM corresponds relatively weak to HEC-RAS predictions. Water depth predictions, on the other hand, differ considerably from HEC-RAS, particularly for higher return periods.