Prise en compte des incertitudes dues au coefficient de rugosité de Manning : application aux modèles hydrodynamiques 1D et 2D

Floodplain map delineation is an essential step in the implementation of the emergency plans provided by the Dam Safety Act (Bill n °93). However, floodplain maps accuracy and quality rely on used models.Two-dimensional modelling has emerged as a reliable approach, which provides local details on the flow. However, 2D model's precision can be altered if the used Manning's n coefficient is the same as for a 1D model. Indeed, Manning's coefficient characterizes different effects, regarding the differences between 1D and 2D modelling. As, estimating « n » roughness parameter is prone to errors, users should be mindful of the impact of these uncertainties on model results.