Application of HEC-HMS Model for Flow Simulation for Dungun River Basin

Abstract

Abstract: The uncertainty in the weather will cause droughts and extreme floods. It can affect agriculture, natural resources, ecosystems, and losses. To overcome water-related problems resulting from climate change and careful care should be given to operations management, reservoirs and water catchment. The purpose of this study is to develop a rainfall runoff model and to assess the runoff potential for the catchment and to calibrate and validate the model and using the calibrated values for future hydrological research. The Hydrological Modelling System (HEC-HMS) was used for the river basin of Sungai Dungun (1463.34 km2), Terengganu. To compute infiltration, transform, and flow routing, methods like Initial and Constant, Clark Unit hydrograph and lag routing were chosen, respectively. The rainfall data for this study were obtained from the Department of Irrigation and Drainage Malaysia (DID), covering from year 2007 to 2018. There are three rainfall gauging stations and one stream flow data stations in the study area. Rainfall-runoff simulation had been conducted using different data set for calibration and validation. Preliminary data shows that there is a clear difference between the observed and simulated peak flows. Model calibration with optimization methods and sensitivity analysis was performed to obtain the optimal parameters for this catchment. The values of the parameters obtained from the calibration show a reasonable difference in peak flow. Model validation using optimized parameter values showed reasonable difference in peak flow. Generally the results of the study showed a good simulation between observed and estimated value with NSE = 0.85, R2 = 0.86, Relative Error Peak = -4.14% and Relative Error Volume = -22.5%