Flash flood hazard zonation based on basin morphometry using remote sensing and GIS techniques: A case study of Wadi Qena basin, Eastern Desert, Egypt

Abstract

Remote Sensing techniques with GIS were used to evaluate flash flood hazard in Wadi Qena. Wadi Qena represents a large, wide, dry and long valley slopes down from the south of the Galala height to the town of Qena. Its southern stretches considered as very promising land for the agriculture expansion. The surface area of Wadi Qena is about 15,588km2. Flash flood hazard in Wadi Qena is evaluating by the integration of some quantitative geo-morphometric parameters and Tropical Rainfall Monitoring Mission (TRMM) satellite data of the last flashflood in 28th January 2013. Streams were automatically extracted from ASTER DEM data. Wadi Qena classified into 151 sub-basins. The various morphometric parameters of Wadi Qena sub-basins have been computed. flash flood hazard map of the most dangerous sub-basins was prepared by combining all the spatial layers of morphometric parameters for the sub-basins included in it by GIS analysis. the majority of the sub-basins range from low to medium hazard degree Except one sub-basin located at the eastern part of the wadi is classified as high hazard degree. This technique may help in evaluating the hydrographic basin and offers a base map delineating both recharge and flooding area. Flash flood has double-edged effects one is a destructive and life terminator, the second is a beneficent, if it can be controlled and directed for the development the community. This technique helps in diminishing the flood hazards and increases recharging the shallow aquifers.