The Scheldt estuary varies greatly over her 160 km course. From Ghent to Doel (Sea Scheldt), the Scheldt has a single channel system. Over this part, the width of the river increases from 50 to 1350 m. Downstream from Doel, in the Netherlands (Western Scheldt), the river meanders over a broad bed with a complex multi-channel system consisting of channels, sandbars, and mudflats and saltmarshes along the edges. In Vlissingen, the river is as wide as 5000 m.
In the past, many anthropogenic operations altered the morphology of the estuary and the river: the edges were reinforced, straightening of the channel on different locations, the land was reclaimed by reclamation, there was dredging and dumping, … In the past, this only happened in interest of safety and accessibility (economy) of the estuary. Today, several of these activities still occur, but the naturalness and balance of the estuary are also considered. As part of this, other management activities are carried out, for instance depoldering. In addition, hydrodynamics also determine the morphodynamics of the system and vice-versa.
In the interest of the three functions of the Scheldt estuary (accessibility, safety and naturalness), the geomorphology is currently closely monitored. Collecting bathymetric data is essential in order to create topographic maps of the water bottom for the entire basin. A lot of research is carried out on composition, transport and deposition of sediment and on channel development, erosion and the influence of sand extraction and dredging and dumping activities.