Eastern Scheldt

The forerunner of today's Eastern Scheldt formed between 7400 and 6300 years ago. This was then an important tidal channel that made contact with the Scheldt at the Brabant Escarpment. Around 3800 years ago, an opening arose in the beach ridge that protected the freshwater marshland behind it from intrusions from the sea. That opening was the mouth of the river Scheldt. Centuries later, this Scheldt estuary deepened and widened again, transforming the entire coastal plain back into a large tidal area.

Between 700 and 800 A.D., one of these tidal channels connected to the then Scheldt at the site of today's Western Scheldt. Starting in the 16th century, the Western Scheldt became the main connection of the Scheldt with the sea. Several storm surges played a role in this as many villages and the town of Reimerswaal flooded. This created a much wider connection between the Eastern Scheldt and the Western Scheldt in that area. This caused major changes in the tidal currents and a wider and deeper estuary mouth. From the end of the 19th century the influence of man became more and more important.

After the 1953 storm surge disaster, work began on the Delta Works. In 1986, the storm surge barrier was completed as a semi-permeable pillar dam that can be completely closed during extreme water levels. With the completion of the Oesterdam in 1986 and the Philips Dam in 1987, the Delta Works around the Eastern Scheldt were complete. As a result of the Delta Works, the Eastern Scheldt and its water regime have changed significantly. The average tidal range, tidal volume, current velocities and freshwater supply have decreased. During storms, sand from the top of the shelves and mudflats washes into the channels and remains there. This causes net degradation of slabs, mudflats and salt marshes. The sand released in the process fills the channels until they are adapted to slower tidal currents and thus a new equilibrium situation. Until then, the Eastern Scheldt suffers from so-called "sand starvation".