The hydrodynamics and fine sediment dynamics modelling in estuarine environments is very important for coastal engineering design and environmentalassessment. This work presents the implementation of a coupled wave-current-sediment transport model with high spatial resolution in a harbour area for a complex estuarine system. The study case is the Río de la Plata with specialattention to the Montevideo Bay area.The numerical model used is the open source TELEMAC-MASCARET Modelling System. Both a two-dimensional depth-averaged (2D) approach and athree-dimensional (3D) approach were implemented. The sediment transport implementation is focused only on fine cohesive sediments. Several modifications are made in the code in order to consider particular relevant conditions and processes in our study case.The model was calibrated and validated based on field data of several variables (sea surface elevation, currents, waves, salinity, suspended sediment concentration, turbidity) at several stations over extended periods of time. The most recent available field data specificallyin the Montevideo Bay area is incorporated.The obtained results with all the modules show good agreement with the measured data, demonstrating to represent satisfactorily the main features of the Río de la Plata dynamics and specifically of the Montevideo coastal area.The influence of the consolidation process is explored using the 2D model. Good agreement is found between the model results and measured verticaldensity profiles in the Montevideo Bay access channel.The 3D numerical model is then used to make a characterization of the hydrodynamics and fine sediment dynamics in the Montevideo Bay. The maincirculation patterns in the bay and their relationship with the local forcings were identified. The non-astronomical tide events showed to have a relevantrole in the water and sediment exchange between the bay and the coastal area, generating important anomalies respect to the astronomical behaviour.It is presented an analysis of the sedimentation patterns in the bay, together with a sediment budget analysis. At the larger scale of the whole estuary themodel results confirms the importance of the current induced stress for the representation of the permanent suspended sediment concentrations and thewave induced stress during the main re-suspension events.Inside the Montevideo Bay the wave forcing plays a relevant role specially on the west areawhich is more exposed to the wave forcing coming through its biggest mouth.However the advection of sediment coming from the near coastal area and the circulation conditions are determinant, and can for example change the bed evolution tendency for similar wave conditions.