Authors: Nurul Atiqah Iliyani Malekke*, Zubaidi Johar, Nasehir Khan E.M.Yahya, Mohd Aminur Rashid Mohd Aminuddin Arumugam, Mohd Hafifi Mat Nazir

River Basin Research Centre, National Hydraulic Institute of Malaysia (NAHRIM),Lot 5377, Jalan Putra Permai, 43300 Seri Kembangan, Selangor, Malaysia.

Corresponding author: [email protected]

E-mail: [email protected]; 

Abstract

Absence of study on hydrological modelling for non-dendritic catchment system has leads to difficulties in understanding the precipitation-runoff condition, designing flood risk assessment and flood mitigation action. The purposed of this study is to developed a hydrological model for Santubong River catchment and assess the possible application of Hydrological Modeling System (HEC-HMS) in estimating peak flow over non-dendritic catchment. Two types of model were created (three outlets and separated outlet)to simulate the peak flow of each model. To account the loss, runoff estimation and flow routing, initial and constant, Clark Unit Hydrograph and Muskigum methods were used respectively. After calibration and validation, separated outlet model peak discharge for O1 (44 m3/s), O2 (51.1 m3/s) and O3 (47.3 m3/s) are well fitted with the observed hydrograph compared to peak discharge in three outlets model. The result for statistical analysis showed that model performance (NSE=0.972) and the correlation (R2=0.984) for separated outlet model is appropriate for hydrological model in Santubong River catchment.

Keywords: Santubong River, non-dendritic, HEC-HMS, peak flow, Nash-Sutcliffe efficiency(NSE)