Uncertainty Assessment of Flood Hazard Due to Levee Breaching

Water resource management and flood forecasting are crucial societal financial stakes requiring reliable predictions of flow parameters (depth, velocity), the accuracy which is often limited by uncertainties in hydrodynamic numerical models. In this study, we assess effect two uncertainty sources, namely breach characteristics induced overtopping roughness coefficient, on water elevations inundation extent. A two-dimensional (2D) hydraulic solver was applied a Monte Carlo integration framework to reach Loire river (France) including about 300 physical parameters. Inundation hazard maps for different scenarios allowed highlighting impact development chronology. Special attention paid proposing relevant sensitivity analysis examine factors influencing depth extent flooding. The spatial vulnerability area levee width exhibits that, with increasing discharge, rise parameter influence accompanied more localized effect. This argues local allow clear understanding hazard. interpretation, highlighted global analysis, showed dependence simulation main studied, i.e., coefficients breaches.