In the watershed, sediment yield spatially and temporarily variable due to the factors for instance land use land cover, type of soil, rainfall distribution, topography and management practices. The main objective of this study was to evaluate spatial and temporal variability of sediment yield on Bilate watershed using Soil and Water Assessment Tool (SWAT) model. Simulation carried out using meteorological and spatial data by dividing watershed in to 23 sub basins with 174 Hydrologic Response Units (HRUs). Model calibration period (2001-2010) and validation period (2011-2015) performed for monthly flow and sediment data using Sequential Uncertainty Fitting (SUFI-2) within SWAT Calibration of Uncertainty Program (SWAT-CUP). Model performance efficiency checked by coefficient of determination (R 2 ), Nash-Sutcliffe model efficiency (E NS ), and observation Standard Deviation Ratio (RSR) and percent bias (PBIAS) indicating good performance of model evaluation. From 23 sub basins, 11 were categorized from moderate to very high (10-26 ton/ha/year) sediment yielding sub basins and selected for sediment management scenarios. Scenarios result showed that average annual sediment yield reduction at entire watershed level after application of grassed waterway, filter strips, terracing and contouring were 54.45%, 30.13%, 63.26% and 59.56% respectively. Also, at treated sub basins level 68.04%, 38.41%, 80.58% and 77.42% of sediment reduction revealed after application of grassed waterway, filter strips, terracing and contouring respectively. It concluded that sediment yield reduction applying terracing was more effective than other conservation measures for affected sub basins.
Keywords: SWAT Model, SUFI-2, Stream Flow, Sediment Yield, Management Scenarios, Bilate Watershed