The floods of September 2002 in the South of France - Hydrological and hydraulic analysis at the Vidourle flood mitigation dams

Abstract

A major hydro-climatic event occurred in Southern France in September 2002. It was particularly severe on the upper catchment of the Vidourle River in the administrative district of the "département du Gard". The reservoirs of the three flood mitigation dams located in that area reached their highest level since they were built in the 60's thus arising interrogations about their safety. We used this significant event to examine the hydrological design studies of the dams. The purpose of the present study was therefore to quantify the hydroclimatic event suffered by the dams. We have tried first to give an evaluation of the occurrence of the rainfall on the catchments controlled by each dam. We have then calculated the hydrographs at the entrance of the reservoirs. Both results were compared with the original hydrological design studies of the dams.