Quantitative Morphometric Analysis of Drainage Basins between Qusseir and Abu Dabbab Area, Red Sea Coast, Egypt using GIS and Remote Sensing Techniques

Abstract

The coastal areas are considered of the promising areas for various types of sustainable development at present and in the future. As well as, this area occupies a large attention of the future planning for officials. The study area is located between Qusseir and Marsa Abu Dabbab along Red Sea coast. It is one of the most important areas. The study area is considered representing a promising and strategic target for urban and industrial expansions, as well as truism villages, but usually it is attacked by natural hazards, especially flash floods although rainfall is scarce in Eastern desert; it is well known for its flash floods with high velocity. The basin morphometric parameters, such as the linear, aerial and relief aspects of the basins, were determined using data (30 m resolution) from the ASTER DEM, Geographic Information System (GIS) and Remote-sensing data such as Landsat Thematic Mapper OLI. The study Linear, Relief and Arial aspects of drainage basins retrieved that, the area includes 25 basins, Wadi Ambagi basin is the largest basin in the study area (1538.24 km²), while wadi Abu Sebekha is the smallest basin in the present study area (11.52 km²). Primary results of this study were the determination that the basins have vast range stream order ranging from 3^rd to 7^th order drainage basins and a drainage pattern mainly of a parallel, dendritic, trellis and rectangular types. The observed drainage density in all basins range from 2.17 to 1.68 with an average is 1.86 km/km². The average of elongation ratio (Re) for all the basins is 0.58, which mean that the most basins in the study area are elongated in shape but is relatively efficient in terms of the runoff discharge due to a large difference in slope. The bifurcation ratio ranges from 2.88 to 5.77, which indicates strong structural control of drainage patterns. Based on the slope map, it can be determined that the areas with high runoff and high erosion rates are those with steeper slopes. The area of rainwater accumulations and its close to mouths of wadis are more exposed to flash flooding. Based on the morphometric parameters which have a direct influence on flooding prone area, the flash flood hazard of sub-basins in the study area are classified into three groups; namely Extreme highly, moderately and Slightly hazard degree. However, most of the study area is environmentally nearly safe.