Flood control in the Netherlands
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The Netherlands has been struggling against floods since the first people settled there. Over 60% of the country lies beneath mean sea-level. Countless people have lost their homes and their lives to floods from the sea or the rivers that could not be held by the flood-defences. The importance of the protection has led the Dutch to dedicate a Department solely to the protection against floods. Furthermore, local waterboards are an extra layer of government specially dedicated to protection against floods and water management. This has resulted in a very high level of flood-protection. Flood-protection remains a continuous point of interest due to the vulnerability of the Dutch economy with regard to flooding.
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[edit] History
At first the inhabitants of the flood-affected areas built artificial dwelling hills called terpen or wierden. On these mounds villages and farms were built. Artificial dwelling hills were built from roughly 500 BC until the coming of the dike somewhere around 1200. Some artificial mounds in the Netherlands "dobbes" or "stellen" were made in the Middle 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 refuge for local people and livestock. The role of the Dutch in land-reclamation has resulted in the Dutch words being now common usage internationally:-
- Dike (also spelled dyke) (Dutch dijk). A dike, in Dutch usage, is an embankment or wall built to keep water from flooding land.
- Polder. This is an area which lays below sea-level and which is defended from flooding.
- 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.
- Dam. A artificial barrier in an estuary, lake or river.
[edit] Drainage Methods
The earliest Dutch polders date from the middle ages. These polders were drained by sluices that opened at low tide to let out water. At the end of the Middle Ages the Dutch started using wind power to drain the land. Windmills pumped water by use of a water wheel or (starting from 1634) the Archimedes' screw. Land below the water level was thus drained. The height at which a single windmill can pump the water is limited. By combining mills, each mill pumps water into a higher reservoir, with the last pumping it out to the river or lake. In the 18th century several molendriegangen (runs of 3 mills), and molenviergangen (runs of 4 mills), were built. The windmills were crucial and essential in reclaiming and preserving the land until the arrival of steam and especially diesel powered pumps.
[edit] Modern developments
The aforementioned steam and diesel pumps led to new developments. Furthermore, mechanization meant that larger projects could be undertaken. The most important are the Zuiderzee Works and the Delta Works.
[edit] Zuiderzee Works
The Zuiderzee Works (Zuiderzeewerken) are a man-made system of dams, land reclamation and water drainage works. The basis of the project was the damming off of the Zuiderzee, a large shallow inlet of the North Sea. This dam is called the Afsluitdijk. It was built in 1932-1933. The dam closed the Zuiderzee and separated it from the North Sea. As result, the Zuider sea became the IJsselmeer — IJssel lake. It is said that during the North Sea flood of 1953 the Afsluitdijk paid for itself in one night, by preventing flooding on the Zuiderzee coast. Following the damming, large areas of land were reclaimed in the newly freshwater lake body by means of polders. The works were performed in several steps from 1920 to 1975.
[edit] Delta Works
In the south-west of the Netherlands a flood defense system was built, called the Delta Works. The Delta Works consist of a series of dams and storm surge barriers. The Delta Works were executed between 1950 and 1997.
[edit] Currently
Flood protection remains an important issue with the Dutch due to relative sea level rise and land subsidence.
[edit] Notorious floods
Among the flood disasters that the Netherlands suffered down the centuries were:-
- Eerste Grote Watersnoodramp (First Great Water Disaster) of December 26, 838. Bishop van Troyes wrote in his diary that all of Frisia was flooded and 2437 lives were lost. This Frisia was then almost all of the low lying areas (nearly 50% of the Netherlands).
- Tweede Vloed (Second Flood) of September 28, 1014. The Abby of Quedlinburg in Saksen spoke of thousands of lost lives. There were few details.
- St. Martin's flood (Sint Martinvloed) November 11, 1099. Not much is known but it was recorded in the Anglo-Saxon Chronicle that the sea was higher and the flooding more extensive than ever before.
- Holland flood of 1212. This flood hit mostly in the north and is said to have had 60,000 victims.
- St. Marcellus flood (Sint Marcellusvloed) January 18, 1219 again hit the north and the Zuiderzee areas; some 36,000 lives were lost.
- 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.
- Eerste Sint Elizabethvloed (First St. Elizabeth Flood) of November 19, 1404. Much of Zeeland and Holland was flooded. This was especially bad for Zeeuwsch-Vlaanderen which had also been flooded in 1375 and again in 1421. The cities IJzendijke and Hugevliet totally disappeared and the Zuudzee was formed until repoldered.
- St. Elizabeth's flood (1421) (Sint Elisabethsvloed) in 1421. This lost much land in Zeeland. Some of it has been reclaimed since.
- Sint Felix Vloed (St. Felix Flood) of November 5, 1530. Oost-Watering was completely lost and Noord-Beveland and Schouwen-Duiveland were severely damaged - all in Zeeland -.
- All Saints' flood (Allerheiligenvloed) on 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 (except for the Zuiderzeevloed of 1916).
- Haarlemmermeer storms of 1836. Since 1530 Haarlemmermeer covering some 6,000 acres (24 km²) had been known as "Waterwolf." It ate up nearby land, other lakes, villages, and ships (wence "Schiphol" or "ship hole") and grew to 42,000 acres (170 km²). Two hurricanes in November and again on Christmas day sent floods to the gates of Amsterdam and down the streets of Leiden. King Wilhelm I & the government in 1838 legislated its draining. A 61 km. long canal and dike were built to surround the lake, and with the largest reciprocating steam engine ever built (and two slightly smaller) some 800,000,000 tons of water (average 13 ft. deep) were pumped out between 1848-52. This was the first real use of mechanical power other than windmills.
- Zuiderzeevloed of January 14, 1916. This flood broke a number of dikes and caused extensive flooding in the immediate low lands (Noord Holland & Friesland). The nation united in the passing of the Laws of 1918 which mandated the Afsluitdijk (Barrier Dam). Preliminary work was started in 1920 with the 2.5 km. Wieringendam and the actual work on the 30 km. Afsluitdijk began in 1927 through 1932 and the roadway was laid in 1933. It reduced the exposed (Zuiderzee) shore from 300 km. to just 45 km. across; making the Zuiderzee a lake named "IJsselmeer."
- North Sea flood of 1953(Watersnoodramp). 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.
- Also 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 the North Sea flood of 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.
