2-dimensional modeling of sediment transport around the Berok River Estuary

Abstract

Berok River is one of the small scales of fishing activities in Central Bangka Regency for mooring boats and loading-unloading activities. The flow of entry and exit for fishing boats at the mouth of the Berok River often experience problems, where the channel becomes shallow due to sedimentation. The behaviour of sediment transport in river mouths is influenced by hydro-oceanographic conditions such as river discharge, current velocity, tides, and geographical conditions. This study aims to determine the characteristics of sediment transport around the Berok River estuary through 2-dimensional numerical modeling. The modeling is conducted using MIKE21 software for the existing conditions and the condition with groynes structure. Two modules are used in MIKE21, namely the Flow Model Flexible Mesh (FM) and the Mud Transport (MT) module. The data used in the sediment transport modeling include tides, bathymetry, wind, and sediment properties. The simulation results show the average sedimentation that occurs around the Berok River estuary is about 0.6 m/year, and the average erosion is about -0.3 m/year. With the groynes structure on the left and right of the river mouth, the average sedimentation rate that occurs is reduced to 0.39 m/year and the average erosion is -0.1 m/year.