The recognition and simulation of silt transport in the Kallo access channel

In the access channel to the Kallo lock, a sedimentation rate of 1,3 cm/day exists. Hence elaborate maintenance dredging works are required. To understand how silt enters the access channel and settles out, one should know all water movements. The flow pattern is generated by three fundamental mechanisms:- tidal filling and emptying of the area- exchange of water between river and basin caused by the passing flow in the river, which creates a circulation in the access channel, so that water is entrained.- exchange of salt and freshwater by density currents (due to differences in salinity)Therefore a programme of field data collection was carried out to measure tidal level, currents, salinity and suspended sediment concentration. The aims of the study are threefold:1. The acquisition of data to reconstruct the local flow pattern, with emphasis on the behaviour of bottom and surface layer.2. The setting up and testing of numerical flow models.3. The setting up and testing of a sediment model to enable the prediction of sediment flow patterns and their impact on maintenance dredging procedures and equipment.This paper describes the successive flow models and the cohesive sediment transport model used in this study. Furthermore, it highlights the difficulties encountered during the calibration of the sediment model