Modelling Discharge, Erosion and Sedimentation at Small Watershed in East Java

Abstract

The land-use change due to human activities and agricultural practices propagate the intensity of hydro-meteorological related disaster (erosion, sedimentation, landslide). Therefore floods and landslides are frequently occurring at Sanenrejo Watershed (±292 km2 ). In this paper, the SWAT (Soil and Water Assessment Tool) model used to evaluate the hydrological processes. The Digital Elevation Model use as the primary input for deriving topographic and physical properties of the watershed. Other input data used for the modelling processes include the soil layer, land-use layer, discharge and climate variables. All of these data are integrated into SWAT to calculate discharge, erosion and sedimentation processes. The existing observed discharge used to calibrate the SWAT output at the watershed outlet. The calibration results obtained an NSE and R2 of 0.62 (satisfactory) and 0.75 (good). NSE validation of 0.5 (satisfactory). This parameter indicates a good model performance to describe the hydrological process in the Sanenrejo watershed. The SWAT than used for the prediction of erosion and sedimentation processes on the watershed.