Hydrological Modeling of the Paligad Watershed (India) Using HSPF Model

Abstract

For hydrological studies, it is well known that each hydrological system behaves differently and in order to effectively manage those systems, it is necessary to understand their behavior. The hydrological component of Hydrological Simulation Program – FORTRAN (HSPF) model was set up and calibrated for Paligad watershed which is a sub-basin of Aglar watershed in the Uttarakhand state of India. The calibration of the model was done manually and an expert advice system called as HSPEXP+ was used to aid calibration. The values of evaluation indicators such as coefficient of determination (R2) Nash-Sutcliffe efficiency, PBIAS and the mean error (RE) were found to be within acceptable range which also indicated good calibration and validation results. The validation results showed that the model nearly simulated the mean monthly runoff with the coefficient of determination (R2) as 0.83 for the year 2015-2016. The total observed annual runoff volume was 32.26 inches, where the value of annual simulated runoff volume was found to be 30.37 inches indicating an error of -5.84% in the estimation of total annual runoff volume. The effect of change in land use/ land cover of the catchment can be evaluated using this model.  This study offers more scope on the management of watershed output in the form of runoff and the impact changes in land use/ land cover on the streamflow from the basin.