Jakarta Bay as one of an area with the densest population in Indonesia became one of the highest contamination level waters in the world includes pollution of debris. Reclamation activities in Jakarta Bay will change the water conditions, and will also affect the distribution of debris at sea. Therefore, this study conducted is to determine the movement of the marine macro debris before and on the condition of the existing reclamation island in the Bay of Jakarta. The method used is simulated by the hydrodynamic model and particle trajectory models using MIKE software. Data needed for the hydrodynamic model, namely wind, tides, bathymetry, and shoreline, while for the trajectory of the particles using a data type of debris, marine macro debris weight, and debris flux. The analysis was performed for hydrodynamic model simulation results and comparison of particle trajectory models. Hydrodynamics simulations indicate if a reclamation island formation does not change significantly in the offshore area, but a simple change in the surface current pattern of the reclamation area, it also causes a decrease in the flow velocity of ± 0.002 to 0.02 m/s at some point. Macro debris particle trajectory simulation shows if after reclamation, macro debris tends to accumulate in the eastern Jakarta Bay in the rainy season (January), as well as in the western and eastern regions during the dry season (July).

At present, marine debris is an important issue in Indonesia. Due to the complex pattern of ocean currents, research on the distribution of marine waste in Indonesia is still very lacking. This study aims to determine the movement of microplastic particles at the Savu Sea National Marine Park. The method used was to simulate the hydrodynamic model and particle trajectory. Data used were wind, tides, bathymetry, coastline, weight of garbage, and garbage fluxes. Analysis was carried out on physical data visualization, hydrodynamic models, and particle trajectory models. The hydrodynamic model simulation shows if the average current velocity ranges from 0,0002 m/s to 0.35 m/s. The particle trajectory showed that microplastic particle movements tend to move to the south, where some of them move west and east of the Savu Sea. Besides being affected by tides, microplastic particle movements in the Savu Sea National Marine Park are also influenced by various currents that pass through the Savu Sea waters, especially by Indonesia Troughflow.