Flood control in the Netherlands
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The Netherlands has been the site of an endless battle between the people and the water. For over two millennia, the Dutch people have been fighting against floods and reclaiming land from the sea. The sea has been driven back, but at a high cost. Countless people have lost homes and lives to the sea or the rivers. Nearly everyone in the Netherlands knows that every square meter of soil came at a high cost, yet giving up is not an option.
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[edit] Early technology
At first the inhabitants of the flood-affected areas built artificial mounds called terpen. The first terpen were build around 500 BC. Terp building ended with the coming of the dike somewhere around 1200. See terp.
Some artificial mounds in the Netherlands are called vliedbergen (singular vliedberg, meaning "refuge mountain"). These were made in the Dark Ages, to provide refuge from rising waters. They are found in large numbers in the south and west of the Netherlands. They were not intended for permanent habitation, but provided temporary place of safety for local people and their animals.
The Dutch built various sorts of water-handling devices to prevent flooding. These are so common in the Netherlands that their Dutch words appear in many Dutch placenames:-
- Dike (also spelled dyke) (Dutch dijk). A dike, in Dutch usage, is an embankment or wall built to keep water from flooding land. For more information see Dike (construction).
- Polder. This is an area of land thus defended from flooding. For more information, see polder.
- Sluice (Dutch sluis or zijl). Often such a sluice gate had a loose flap which let water through at low tide but shut at high tide. For more information see sluice.
- Dam. See dam. Such a dam on a river often contained a sluice gate.
[edit] Windmills
In Europe, windmills were developed in the Middle Ages. The earliest mills were probably grinding mills. They were mounted on city walls and could not be turned into the wind. With some subsequent development mills became versatile in windy regions for all kind of industry, most notably grain grinding mills, sawmills (late 16th century), threshing, and, by applying Archimedes' screws, pumping mills.
They soon became the major energy source in the low lands, where the older watermills could hardly operate due to the lack of height difference in the water ways. The pumping mills allowed the drainage of the Dutch wetlands to claim new land, polders. By continuously pumping water out to the rivers, land below sea level could be created. The earliest Dutch polders date from the middle ages, the first lake was emptied by Jan Leeghwater from 1607. To claim ever more land it became necessary to build series of mills (molengang, "run of mills"]), because an Archimedes screw can only efficiently pump water for a limited height. Each mill pumps water into a higher reservoir, with the last pumping it out to the river. In the 18th century several molendriegangen (runs of 3 mills), and molenviergangen (runs of 4 mills), were built. The largest preserved run of mills in Kinderdijk was awarded world heritage status in 1997.
The mills were crucial and essential in reclaiming and preserving the land and until the arrival of steam and especially diesel powered pumps, they were an extremely common sight in the Dutch landscape. The system used was ingenious as well as practical and simple. A series of mills, the number depending on the size of the polder, were put at different heights and so the water could be transported from the polders below sea level to a higher nearby river or canal.
[edit] Modern developments
[edit] Zuiderzee Works
The Zuiderzee Works (Zuiderzeewerken) are a man-made system of dams, land reclamation and water drainage works, and the largest hydraulic engineering project undertaken by the Netherlands during the twentieth century. The project involved damming off of the Zuiderzee, a large shallow inlet of the North Sea, and reclaiming land in the newly enclosed water body by means of polders. The works were performed in several steps from 1920 to 1975, the chief project being the Afsluitdijk dam built in 1932-1933, which effectively separated the Zuiderzee from the North Sea. It is said that in the North Sea flood of 1953 the Afsluitdijk paid for itself in one night, by preventing flooding on the Zuiderzee coast. As result, the Zuidersea became the IJsselmeer — IJssel lake.
[edit] Delta Works
In the North Sea Flood of 1953, breaks in the dikes and seawalls killed 1,835 people and forced the evacuation of 70,000 more. 10,000 animals drowned, and 4,500 buildings were destroyed. To prevent such a tragedy from happening again, an ambitious flood defense system in the province of Zeeland was conceived and deployed, called the Delta Works. The most impressive barrier of Oosterscheldekering was built in 1976-1986, has gates which can be closed during extremely high sea tides. The Maeslantkering barrier consists of two movable gates which protect Rotterdam port from flooding.
[edit] Notorious floods
Among the flood disasters that the Netherlands suffered down the centuries were:-
- St. Lucia's flood (Sint-Luciavloed) in 1287. This permanently lost much land in what is now the Waddenzee and IJsselmeer and enlarged the inland lake Almere into the Zuiderzee.
- St. Elizabeth's flood (1421) (Sint Elisabethsvloed) in 1421. This lost much land in Zeeland. Some of it has been reclaimed since.
- All Saints' flood (Allerheiligenvloed) on 1 November 1 1570. It affected Egmond and Bergen op Zoom and Saeftinghe and permanently drowned land in Zeeland.
- Christmas flood 1717 (Kerstvloed 1717). It was the last large flood in the north of the Netherlands.
- North Sea flood of 1953: On the night of 31 January/1 February 1953 a storm tide surge broke many dikes in the provinces of Zeeland and Zuidholland and Noord-Brabant and caused much flooding and death. This pushed the Dutch government into ordering the Delta Works.
- And see Floods in the Netherlands.
[edit] Drowned villages
"Drowned village" is the term used in the Netherlands for settlements which have been destroyed by water, either with a natural or human cause, and were not rebuilt but completely destroyed or abandoned by its inhabitants. Thanks to a remarkable amount of Dutch records reaching as far back as the Dark ages much information about these villages is preserved today ranging from the entire story of their destruction to just their name. The last 2 villages to be "drowned by the water" were Schuring and Capelle in 1953. See List of settlements lost to floods in the Netherlands.
[edit] External links
- DeltaWorks.Org - Website about the flood of 1953 and the construction of the DeltaWorks.
