Simulation of Sediment Yield using SWAT Model in Fincha Watershed, Ethiopia

Abstract

The soil and water assessment tool (SWAT) model was applied to simulate the sediment yield from the Fincha watershed (area 3,251 km2), located in Western Oromiya Regional State, Ethiopia. The purpose of the study was to examine the applicability of the SWAT model in a watershed with a high sediment runoff modulus. The automated calibration process was used to calibrate the model parameters using time series data from 1987 to 1996. Data from 1997 to 2006 were used to validate the model using the input parameter set. Time series plots and the statistical measures of coefficient of determination (R2) and Nash-Sutcliffe efficiency (ENS) were used to evaluate the performance of the model. The predicted and observed sediment yields generally matched well. The results of the model calibration and validation showed reliable estimates of monthly sediment yield with R2 = 0.82 and ENS = 0.80 during the calibration period and R2 = 0.80 and ENS = 0.78 during the validation period. This study showed that the SWAT model is capable of predicting sediment yields and hence can be used as a tool for water resources planning and management in the study watershed.