Estimation des crues de référence par approchegéomorphologique

Estimate of the reference floods by geomorphological approach

Centre d’Etudes Techniques de l’Equipement Méditerranée Pôle d’activités – CS 70499 13593 Aix-en-Provence cedex 3

Auteur de correspondance : jose-luis.delgado@equipement.gouv.fr

Abstract

Estimate of the reference floods by geomorphological approach.The Department of Ecology and Durable Development has recommended, since 1996, to draw up the mapping of potential flooding zones by an approach qualified as “hydrogeomorphological”.The relevance of this naturalistic approach – in order to delimit the different geomorphological high, mean and low water beds that form the functional alluvial plains of the rivers – was checked, particularly in the Mediterranean area, during the recent floods of november 1999 in the Aude department and of september 2002 in the Gard department. An estimate of the maximal flows that flood the entire surface of the alluvial plains is generally possible with the help of hydraulic modelling by homogeneous section.Application results, particularly in the Mediterranean area, are compared to results of other methods for the reference flood estimate.