For the construction of a morphodynamic model of the Western Scheldt a comparison between the resulring sediment transport using a 2Dh hydrodynamic and a 30 hydrodynamic model is made. For the area and subject of interest the secondary currents are of major importance, for it determines up to 40% of the siltation in the shipping channel. The distinction of the secondary currents in a longitudinal and transversal direction, with respect to the depth averaged current, is made in order to cakulate the contribution to the resurting sediment transport, It is shown that on different locations different driving mechanisms are dominant.