Tempête Alex du 2 octobre 2020 dans les Alpes-Maritimes : une contribution de la communauté scientifique à l’estimation des débits de pointe des crues

Abstract

The Alex storm caused particularly catastrophic floods in the Roya, Tinée and Vésubie valleys (south-eastern France) on 2 October 2020. This event will certainly serve as a reference for flood risk management in the future and it is important to document it as far as possible, in order to preserve its memory and enable further studies. Different national services and operators have been involved to gather and consolidate datasets describing this event. This article presents a contribution from the scientific community to the reconstruction of the event’s peak discharges, conducted within the HyMeX research programme. Field cross section surveys made it possible to obtain 32 peak discharge estimates, contributing to a detailed description of the flood genesis on the main rivers and their small tributaries.