Hydrological Simulation of Silver Creek Watershed using Soil and Water Assessment Tool (SWAT)

Abstract

Silver Creek Watershed has a basin of 1213.11 km2, located in Southern part of Illinois State (U.S.A), including highland silver lake and its east fork tributary. This research employs (Soil and Water Assessment Tool) to analyze the watershed as a function of land use parameters. Diff erent parameters have been considered in sensitivity analysis to determine the most sensitive parameters for fl ow rate calibration within diff erent hydrological response units (HRUs). Inputs parameters include precipitations and meteorological data such as solar radiation, wind speed and direction, temperature, and relative humidity. Model was calibrated with measured daily data for Troy gage station. The main objective was to simulate and calibrate the fl ow rate with SWAT model. Uncertainty analysis has been performed with SUFI-2 (Sequential Uncertainty Fitting Version-2) which is interfaced with SWAT applying iSWAT (generic coupling format program). Correlation between several stations within the domain has been calculated which showed a good range of Correlation (R2) values which means the pattern of meteorological data was evenly distributed. Finally based on the root mean of squares error (RMSE), (R2), NSE, and P-BIAS values, the accuracy of the calibration has been determined