The Delta Works of Zeeland
When you come to visit Zeeland, you will pass one or more flood barriers which form the Delta Works. It was in the night of 31 January to 1 February 1953 that the south-west of The Netherlands was devastated by a disastrous North Sea flood. Vast tracts of Zeeland were inundated. There, and in the neighbouring province of Zuid-Holland and the West-Brabant region, people fled to their attics, roofs and sheds. In all, 1,836 people lost their lives.
The Works were built to prevent the Netherlands ever again being struck so hard. The delta’s estuaries were closed off by dikes, dams and sluices. Sea defences were raised to ‘delta level’, namely five metres above standard known as NAP, roughly that of the summer flood tide of Amsterdam when it was open to the sea.
Since that time, the coast of Zeeland has built up a chain of sea defences: the Haringvlietdam, Grevelingendam, Brouwersdam, Veerse Gatdam, Zandkreekdam, Philipsdam, Oesterdam and the Oosterschelde barrier. With the islands now connected by this chain, Zeeland is much more accessible than previously.
The Oosterscheldekering flood barrier is by far the best-known link in the Delta Works, and was the last to be completed. It leaves the Oosterschelde estuary partially open to the sea – the original plan was to close it entirely. During early construction, and after some protest, it became clear that closure would mean the loss of an area of unique natural value. The barrier was redesigned as a dam with sliding gates to be closed during heavy storms or spring tides. Stunning in all dimensions, it is called the Eighth Wonder of the World by some.
In Zeeland the Haringvlietdam has some special aspects. Lying between Voorne-Putten and Goeree-Overflakkee, it is a route much taken by travellers, and marine creatures. Five kilometres long, it has 17 spillways for excess water from the Rhine and Maas rivers to flow into the North Sea. Fish and other marine creatures can use special tunnels in its pillars to enter or exit the sea even when the dams are closed.
At 10.5 kilometres, the Oesterdam is the longest of the Delta Works dams, connecting Tholen to Zuid-Beveland. It separates nature from shipping. To the west, the Oosterschelde stretches out, to the east, maritime traffic makes its way along the Schelde-Rhine canal, passing smoothly through the locks of the De Kreekraksluizen.
The Zandkreekdam was the first dam in Zeeland to be completed. In those early days, when the bridge over the locks was open, road traffic would get severely backed up. To solve this, a bypass bridge was built alongside the Veerse Meer. This took shape when the Zandkreekdam closed the estuary of the Veerse Gat, where another was erected. The lake’s full closure restricted its oxygen supply, with algae growth and odours as a result. The dam was modified by inserting two concrete tubes, 80 metres long. Thanks to this culvert, known as the Katse Heule, the Veerse Meer lake looks good, smells good and is partially tidal again.
The seven-kilometre Philipsdam lies between the Grevelingendam and Sint Philipsland. It closes the Krammer and Volkerak water bodies off from the Oosterschelde estuary. The sluice gates have a complex system of pipes and pumps to create a screen of air bubbles which prevents the salt water of the Oosterschelde from entering the fresh water of the Volkerak. One benefit of the resulting silting up of the salting marshes is a huge increase in the bird population.
The building of the Grevelingendam created a new lake, the Grevelingenmeer. The largest freshwater lake in Western Europe, it is a popular place for water sport lovers – with extra special appeal to divers. The dam is six kilometres long connects up Schouwen-Duiveland and Goeree-Overflakkee. To build it, an innovative method was used, dropping concrete blocks in place from a suspended cableway. The same technique was applied again on other sites, including for the Brouwersdam.
The 6.5 kilometres of the Brouwersdam separate the Grevelingen lake from the North Sea, carrying road traffic between Schouwen-Duiveland and Goeree-Overflakkee. It’s an all-weather favourite for water sport disciples: the North Sea side is a mecca for kite surfers, while windsurfers congregate on the Grevelingen.
Journey through elements
The long-distance Deltaroute is a great way to feel the elements around the Delta Works. It runs for 148 kilometres over the Oosterschelde flood barrier, the Grevelingendam and the Oesterdam.