Journal
Environmental Modelling and Software
Paper Keyword
Bottom-up hazard vulnerability,Coupled hydrological-hydraulic model,Flood frequency analysis
Abstract
Accurately quantifying and assessing the flood risks is critical for flood hazard mitigation and prevention. This study proposed a new integrated flood risk assessment framework to map flood risk, hazard and vulnerability by coupling the HEC-HMS hydrological model, the HEC-RAS 1D and 2D hydraulic models, and a bottom-up hazard vulnerability analysis. The Old Brahmaputra River floodplain of Bangladesh, a flood-prone region, was chosen as a case study. The coupled hydrological-hydraulic model shows a comparable robust performance in both cali bration and validation periods with Nash-Sutcliffe efficiency coefficient = 0.93 (0.81), coefficient of determi nation = 0.95 (0.89), and percent bias =-1.17%(2.40%)for the calibration (validation) period. Our results indicate that the assessed risk levels are roughly consistent with the overall property distribution and flood hazard potential in the study area. The proposed framework and associated findings are valuable for devel oping adaptation strategies and early-warning systems to reduce flood impacts in the future.
