Three-Dimensional Hydrodynamic Modelling to Estimate Sediment Rate in Lamong Bay

Abstract Lamong Bay Terminal, part of Tanjung Perak Port in Surabaya, functions as a container terminal. The port in the Surabaya area causes high ship traffic activity in the waters of Lamong Bay and sediment may be carried away from rivers heading towards the sea. The sedimentation process in waters can cause problems because it can cause shallowing of the waters, so it is necessary to maintain and monitor the depth of shipping lanes to maintain the safety of sea traffic. Therefore, understanding the hydrodynamics of seawater and sediment movement in the water region is necessary for successful dredging operations and assessing the impact of silt on port areas. In this research, the approach used to determine current patterns and sediment distribution was through the application of a numerical model with three– dimensional baroclinic hydrodynamic equations. The numerical modeling study in this research uses tidal data, sediment samples, salinity, and temperature to determine current patterns and the rate of sediment distribution. This process is carried out periodically and continuously as part of the evaluation of Lamong Bay Terminal. The results can serve as a reference for dredging planning to maintain the depth of the waters at the Lamong Bay Terminal. In this study, the highest current velocity was obtained at the time of spring tide reaching 0.9 ms −1 and at the neap tide of 0.4 ms −1 . The sediment distribution pattern in the waters of Lamong Bay affected the existence of the pier and the morphological conditions of the seabed. The largest siltation or sedimentation that has occurred at Lamong Bay Port is 0.055 m/month near the jetty, thus depth monitoring is needed in this area, regularly. This study supports SDG 9 by advancing resilient infrastructure solutions to manage the sedimentation process in waters.