Impact of Land Use Change Study on Reservoir’s Sediment Yield using SWAT Model Platform

Abstract

The overall goal of this study is to evaluate the effect of land use on reservoir’s sediment yield by applying Arc SWAT model interface with GIS and identify the vulnerable sub basin in Neshi dam watershed. Different input data were collected from different sources including Ministry of Water, Irrigation and Energy, and Ethiopia National Meteorological Agency. The study was done using historical records of nineteen years for Neshi Watershed. The calibrated flow and sediment for the 1992-2001 years gave R2 0.77, 0.92 and NES 0.64, 0.96, respectively. The validated flow and sediment for the 2002-2008 years gave R2 0.72, 0.93 and NES 0.75, 0.95, respectively.In this study the SWAT model yields average annual sediment load of 634.49, 516.82 and 542.56 ton/ha/yr for land use change of 1990, 2010 and 2017, respectively at Neshi outlet dam site. Therefore, the issue of land use change impact on sediment yield on reservoir as part of the integrated adaptation mitigation measures program in order to achieve sustainable development is very relevant. The output of this study can help planners, decision makers and other stakeholders to plan and implement appropriate soil and water conservation strategies.