HARBOUR INLETS ON TIDAL ESTUARIES

Abstract

Two important points should be considered, if a harbour mouth is planned, on a river: 1. The traffic conditions especially the navigation must be considered (i.e. large width of the mouth) 2. The sedimentation should, be small (i.e. small width of the mouth) These conditions are contradictory. Harbour mouths are lateral enlargements. The current doesn't follow these enlargements, a separation sheet forms which is characterized by eddies. A more or less great mass of water is in movement in the enlargement. These rotating movements are called "vortices". One distinguishes "primary vortices", "secondary vortices" etc. depending on the initiating current (Fig. 1).