SEDIMENT DISTRIBUTION ANALYSIS IN KURAU RIVER ESTUARY CENTRAL BANGKA USING HYDRODYNAMICS MODELING

• Main Author: Ferriska, Okta
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/65789
• Institution: Institut Teknologi Bandung

The Kurau watershed is located in Kurau Village, Central Bangka, Bangka Belitung Islands Province. The Kurau watershed has a big role in the survival of the Kurau villager, especially the Kurau River estuary. The estuary of the Kurau River is an important aspect in supporting the economy of the villager, because it is the entry and exit channel for boats with the dominance of people who work there as fishermen. In addition, the estuary of the Kurau River is also a shipping route for maritime tourism destinations to 3 (three) tourist attractions, namely Ketawai Island, Gusung Island and Bebuar Island. However, according to the Head of the Director General of Water Resources (SDA) of the Bangka Belitung River Basin, the estuary of the Kurau River conduced sedimentation of 221,232.598 tons/year. Estuary sedimentation can result in silting of the river mouth and hamper all activities related to the entry and exit of boats passing through the Kurau River estuary. As an effort to see the dynamics of sedimentation that occurs at the estuary of the Kurau River Central Bangka, in this study a hydrodynamic modeling using Delft3D software was carried out based on analysis of current data and its relation to the tidal phenomenon when the low and high tides period (spring tide) occurs. From the results obtained, the current in the Kurau River estuary during the high tide period has a dominant current pattern towards the northwest with a speed of 0.041 m/s which occurs in the sea 1 domain and moves towards the estuary domain. Meanwhile, during the low tide period, the current pattern tends to be northwest to north due to a change in the bathymetric elevation value in front of the mouth of the estuary which causes a change in current direction and a slowdown in current velocity. For the analysis of sedimentation that occurred at the mouth of the Kurau River, the sedimentation process was dominated by sediment carried by the Kurau River. This is because the discharge of the Kurau River has a bigger role in the sediment transport process than the current from the sea. The topographic elevation in front of the Kurau River estuary and in the coastal area also has a very low elevation value, which is close to the value of 0 (zero) to the value of MSL (Mean Sea Level) with a considerable distance. This causes the sediment transport process from the river mouth to the sea to be disrupted when the low tides. Meanwhile, for the distribution of sediment at the Kurau River estuary during the high tides, the movement of sediment will follow the direction of the current from the sea, so that it will cause sedimentation to the north to the northwest from the Kurau River estuary and the coasts.