Morphometric Analysis of Didessa River Catchment in Blue Nile Basin, Western Ethiopia

Abstract

In the present paper an attempt has been made to study the morphometric characteristics of Didessa catchment which is part of Blue Nile River basin located in South Western part of Ethiopia. The study focused on evaluating the effect of morphometric parameters on the hydrology and morphology of the basin. The primary data for this study was an elevation data in raster format (Digital Elevation Model or DEM) also known as ASTER DEM of 30m spatial resolution. Stream networks and watersheds were delineated in ArcGIS 10.1 software environment by utilizing ArcHydro and Spatial Analyst Tools. Based on the results of the software analysis, linear, areal, and relief aspects of the basin were computed. The result indicates that Geo-spatial techniques and DEMs data are efficient for extracting stream networks and characterizing the morphology of watersheds as well as computing the various indices of drainage basin morphometry. Hence, the results of this study provide useful inputs for watershed level planning and management.Keywords: ASTER DEM, ArcHydro, Hydrology, Watershed