THE GEOMORPHOLOGIC AND GEOLOGIC ROLE ON THE DEVELOPMENT OF THE WATER RESOURCES, ESH EL MALLAHA AREA, EASTERN DESERT, EGYPT.

Abstract

Esh El Mal/aha area is located at the southwestern margin of the Gulf of Suez, between latitudes 27" 30' m1d 28° 00' Nand longitudes 33° 00' and 33° 30' E, covering an area of approximately 5175 km2. It is located in the arid zone of Egypt.

Geomorphologica/ly, Esh El Mal/aha area is discriminated into three main units; the watershed areas (highlands), the water collectors (low-lands) and the coastal plain. 1- The watershed areas are represented by the high lands, which receive the torrential rainwater and are distinguished into four units, which are Red Sea Mountainous terrains, the Ridges (EL Zeit and Esh El Mal/aha ridges}, Abu Shaar plateau and hilly areas. 2- The water collectors are represented by the low land areas which are distinguished into two types; the drainage basins and the morphotectonic depressions. There are four drainage basins extending westward to the main watershed area namely

Wadi El Dib, Wadi Abu Had, Wadi El Mal/aha and Wadi Bali with an area ranges between

308.85 km2 (Wadi Abu Had) and 1704.3 km2 (Wadi El Mal/aha).

The hydrographic basins and their subbasins are morphometrically analyzed and their flash flood strength degrees are assessed depending on twenty two morphometric parameters. namely El Dib 2 , 3 , 5 and 7, Abu Had 3, El Mal/aha 2 and Bali 3 have extremely high strength (degree 5) while the sub-basins Abu Had 2 and El Mal/aha 3 have weak strength (degree I). On the other hand, the main hydrographic basins El Dib and Bali represent extremely high strength (degree 5}, EI Mal/aha basin represents moderate flood strength (degree 3) and Abu Had is a weak flood strength (degree I).