In 1966 some communities in the western part of Noord-Brabant decided to build a harbour and industrial area (IHM) near Moerdijk. This area can be reached by ocean-going vessels. These vessels have a maximum draught of 8,40 meters. Since the closure of the Haringvliet and the Volkerak in 1970, there is deposition of silt and sand in the whole area. The depth of the Hollandsch Diep will decrease gradually. For that reason the vessels have to use a dregded crossing channel in the Hollandsch Diep to reach the IHM. This channel has to be redredged almost every year. Because of the decreasing depth in the Hollandsch Diep, the amounts of the dredged material and the costs increase. This report is the result of a project at the Department of Transport and Public Works. The subject of this project was how to decrease the deposition of sediment in this crossing channel to the IHM. During this project the process of deposition and erosion of sediment is examined with numeric models for the simulation of the water movement and the sediment transport. In the models the deposition in the crossing channel was 20% more than in the surrounding. In reality the deposition in the crossing channel is 100 to 200% more than in the surrounding. With these models also are examined the changes in sediment transport for a new discharge controlprogramme of the Haringvlietsluizen (HV2-min), for a deeper channel and for three alternatives. The computed changes as a result of a deeper channel were few, because of the inaccurate When the discharge control programme of the Haringvlietsluizen will be changed, the deposition in the whole area will reduce. Just after changing the discharge control the deposition in the channel will increase. This is a temporary increase till there is an equilibrium depth. In alternative 1 (a submerged dam upstream of the channel) only in the northern part ot the channel there will be scour. In alternative 2 (semi-closure of the Zuid-Hollandsch Diep) there are more effects. In the whole channel the deposition will decrease and in the Zuid-Hollandsch Diep there is only deposition because of diffusion and tide difference. In the entrance of the Zuid-Hollandsch Diep the deposition will increase. Alternative 3 (sediment reservoir) has a local influence only and has a small influence in the area as a whole