Evaluation of potential dam break flood risks of the cascade dams Mexa and Bougous (El Taref, Algeria)

Abstract

Abstract The implementation of Bougous dam at 5 km upstream of Mexa dam permits to compensate the storage capacity and to reduce sediment yields in the later, however, these advantages must be associated to the fact that the presence of two large dams in the region poses in case of a dam break event a potential threat to human life and property. Indeed, in this study a numerical simulation of the dam break wave propagation resulting from the failure of the two dams was performed using the two-dimensional hydrodynamic model Telemac-2D, in order to estimate the impacts on constructions located in the downstream valley. The simulation results exported to GIS platform allowed the elaboration of cartographic materials depicting the hydraulic characteristics of the flood wave and its arrival times at key locations, which constitute very useful information for the authorities to avoid significant loss in case of the failure of Bougous and Mexa dams.