Author(s): Vito Bacchi; Cedric Goeury; Fabrice Zaoui; Kamal El Kadi Abderrezzak; Sophie Bacchi; Sara Pavan

Linked Author(s): Vito Bacchi, Fabrice Zaoui, Kamal El Kadi Abderrezzak, Sara Pavan

Keywords: Flooding hazard; Levee breaches; Uncertainty quantification

Abstract: The objective of this study is to propose a new methodology for the assessment of flood hazard induced by the formation of levee breaches due to overtopping flows. The proposed methodology relies on the definition of a new breach model and on the flood hazard assessment (i.e. water height in area of interest) through a deterministic simulation. The methodology is implemented in the open-source hydrodynamic suite of solvers TELEMAC-MASCARET (www.opentelemac.org) and applied to the Loire river using the two-dimensional (2D) depth-averaged hydrodynamic code TELEMAC-2D. We chose a flood scenario corresponding to a return period of around 500 years and we compared results to those obtained by performing 3,000 Monte-Carlo simulations using uniform distribution of the model parameters. Results suggest that the deterministic simulation should be completed by a set of well-chosen deterministic scenarios in order to cover the large uncertainty showed by the computational costly Monte-Carlo simulations.

DOI: https://doi.org/10.3850/IAHR-39WC2521711920221210

Year: 2022