Analysis of sediment movement at Sg. Perlis: erosion or deposition

Abstract

Sediment movement is essential to protect the environment near the river as it will affect the bed condition, depth of water and the infrastructure along the waterside. Hence, a study was conducted at Sg. Perlis to analyze the sediment characteristics and then determine the type of sediment movement which are affected by the characteristics of sediment. The parameters needed are velocities of current flow measured from Sg. Perlis and characteristics of sediment which are average particle size, D50 and plasticity index, PI. Velocities of current flow used to compute the values of bed shear stresses while both of average particle size, D50 and plasticity index, PI, are used to compute the values of critical shear stresses. The results have reported that the values of bed shear stresses, τo, are greater than the values of critical shear stresses, τc, which computed either by using average particle size, D50 or plasticity index, PI (τo > τc). Thus, erosion process occurs instead of deposition process at Sg. Perlis. Sediments tend to erode and move along the river toward the sea.