Runoff and Sediment Yield Modeling Using Arc SWAT -A Case of Meki River Watershed

The objective of this study was to model the runoff and sediment yield to control soil erosion and sedimentation problems of the Meki River Watershed. The main materials and methodology were Arc GIS, Arc SWAT, Rainbow, excel stat, data collection, data preparation and quality assurance, data analysis and model setup, running model, model performance evaluation and model result interpretation. Simulation of the stream flow of Meki River watershed for the period from 1993 – 2010 and sediment yield was computed by developing sediment rating curve. The main results of stream flow calibration and validation are; coefficient of determination (R²) = 0.81, Nash – Sutcliffe model efficiency (NSE) = 0.76, percent bias (Pbias) = 18 and coefficient of determination (R²) = 0.81, Nash – Sutcliffe model efficiency (NSE) = 0.74, percent bias (Pbias) =17.1. As a result of the study, the total annual runoff and sediment yield were determined as 367.95mm and 75.896 ton/ha/yr. respectively.