Flood risk assessment and management in urban areas: a case study in Bechar City, South Western Algeria

Flood has always been considered as one of the natural catastrophes that accompanies with huge losses and damages, which affect the lives of human beings. The present paper presents a flood risk assessment approach for Bechar city, an urban area in Southwest of Algeria using hydrologic engineering centres-river analysis system (HEC-RAS). In order to achieve better floodplain management in the study area, a suite of solutions were developed, taking into account hydraulic, infrastructure, environmental, geomorphic, economic and social considerations. Some of the key solutions identified included: 1) redevelopment of the Bechar Wadi over the entire urbanised area, on a width of the bed of the Wadi whose sizing will be ensured by a detailed study; 2) evacuation of excess flow through a bypass channel to Tigheline Wadi; 3) establishment of a dam in downstream of El Abiad Wadi. The results of this study will be of great help to the decision makers in the field of floodplain management, especially the involved government's department, to make a proper plan for future development.