Study of Sediment Distribution in Tanjung Pasir Banten Based on Bed Load Data

Abstract

The Tanjung Pasir waters area in Tangerang is a pilot project where a sea dike (WLP-Waduk Lepas Pantai) will be built, which doubles as a sea wall and as a raw water provider for the Tangerang Regency and surrounding areas. In planning WLP coastal buildings, one of the main problems is the presence of siltation due to sedimentation caused by sediment transport. This process is closely related to the sediment distribution from the bed load. So far, there have not been many studies on sedimentation in Tanjung Pasir waters, so as an initial study, an analysis of sediment distribution was carried out. This study aims to the mechanism of sedimentation distribution based on grain size data from bed load to support the National Capital Integrated Coastal Development (NCICD) WLP development plan. The methods used in this study are sediment sampling in the field, laboratory analysis, and descriptive analysis to describe the relationship between the phenomena studied and the bathymetry and current factors that occur in Tanjung Pasir waters. Based on the results of this study, it is known that the grain size of the bed load ranges from 0.085 mm - 2.0 mm. The sediment type consists of two kinds, namely sand, and silt mixed with quite a lot of shellfish. The type of sediment seen from the value of d50 consists of very fine sand, fine sand, medium sand, and silt. It was dominated by very fine sand. Bathymetry has a depth of 1 m-20 meters, there is no significant relationship between bathymetry and bed load grain size. The current speed is 0.24 m/s with the dominant current direction east to southeast, belonging to the fast current category, there is a close relationship between the current speed and the distribution of sediment sizes where coarse-grained deposits are deposited in areas with fast current speeds. The speed of this current affects the process of transporting, depositing, and distributing sediments.