Afsluitdijk

The Afsluitdijk (Closure-dike) is a major dam in the Netherlands, constructed between 1927 and 1933 and running from Den Oever on Wieringen in North Holland province, to the village of Zurich (mun. Wûnseradiel) in Fryslân province, over a length of 32 km and a width of 90 m, at an initial height of 7.25 m above sea-level ( 53° 00' 00" N  05° 10' 00" E) . It is a fundamental part of the larger Zuiderzee Works, damming off the Zuiderzee, a salt water inlet of the North Sea and turning it into the fresh water lake of the IJsselmeer. Download high resolution version (888x561, 128 KB)This is a file from the Wikimedia Commons, a repository of free content hosted by the Wikimedia Foundation. ... Download high resolution version (888x561, 128 KB)This is a file from the Wikimedia Commons, a repository of free content hosted by the Wikimedia Foundation. ... 1927 was a common year starting on Saturday (link will take you to calendar). ... 1933 was a common year starting on Sunday (link will take you to calendar). ... Satellite image of the northernmost part of the Dutch province of North Holland, showing Wieringen (bottom right) and the island of Texel (center). ... North Holland: (Dutch: Noord-Holland) is a province of the Netherlands, located in the northwest part of the country. ... Wûnseradiel is a municipality in the Fryslân province of the northern Netherlands, at the eastern end of the Afsluitdijk. ... This article is about the province Friesland in the Netherlands. ... KM, Km, or km may stand for: Khmer language (ISO 639 alpha-2, km) Kilometre/Kilometer (only km in minuscule is the correct representation of kilometer as an SI unit of length) Kinemantra Meditation Knowledge management, in the field of Library and information science Knowledge Machine, the KM knowledge representation... The metre, symbol: m, is the basic unit of distance (or of length, in the parlance of the physical sciences) in the International System of Units. ... For considerations of sea level change, in particular rise associated with possible global warming, see sea level rise. ... The 32 km long Afsluitdijk separates the IJsselmeer from the North Sea, protecting thousands of km² of land. ... Landsat photo The Zuider Zee (Dutch: Zuiderzee, pronounced ZIGH-der-zee) was a former shallow inlet of the North Sea in the northwest of the Netherlands, extending about 100 km inland and at most 50 km wide, with an overall depth of about 4 to 5 meters and a coastline... The North Sea is a sea of the Atlantic Ocean, located between the coasts of Norway and Denmark in the east, the coast of the British Isles in the west, and the German, Dutch, Belgian and French coasts in the south. ... IJsselmeer seen from space The IJsselmeer (or Lake IJssel) is a shallow lake of some 1250 km² in the central Netherlands bordering the provinces of Flevoland, North Holland and Friesland, with an average depth of 5 to 6 m. ...

Previous experiences had demonstrated that till (boulder clay), rather than just sand or clay, was the best primary material for a structure like the Afsluitdijk, with the added benefit that till was in plentiful supply in the area; it could be retrieved in large quantities by simply dredging it from the bottom of the Zuiderzee. Work started at four points: on both sides of the mainland and on two specially made construction-islands (Kornwerderzand and Breezand) along the line of the future dike. This article is about glacial sediments, for other uses see till (disambiguation). ...

From these points the dike slowly grew by ships depositing till into the open sea in two parallel lines. Sand was then poured in between the two dams and as it emerged above the surface was then covered by another layer of till. The nascent dike was then strengthened from land by basalt rocks and mats of willow switch at its base. The dike could then be finished off by raising it further with sand and finally clay for the surface of the dike, on which grass was planted.

Construction progressed better than expected; at three points along the line of the dike there were deeper underwater trenches where the tidal current was much stronger than elsewhere. These had been considered to be major obstacles to completing the dike, but all of them proved to be relatively straightforward. On May 28, 1932, two years earlier than initially thought, the Zuiderzee ceased to be as the last tidal trench of the Vlieter was closed by a final bucket of till. The IJsselmeer was born, even though it was still salty at the time. May 28 is the 148th day of the year in the Gregorian calendar (149th in leap years). ... 1932 is a leap year starting on a Friday. ...

The dike itself however was not finished yet as it still needed to be brought up to its required height and a road linking Friesland and North Holland (the current A7/E22 motorway) also remained to be built. It would not be until September 25, 1933, that the Afsluitdijk was officially opened, with a monument marking the spot where the dike had been closed. The amount of material used is estimated at 23 million m³ of sand and 13.5 million m³ of till and over the years an average of around 4 to 5000 workers were involved with the construction every day, relieving some of the unemployment following the Great Depression. September 25 is the 268th day of the year (269th in leap years). ... 1933 was a common year starting on Sunday (link will take you to calendar). ... The Great Depression was a massive global economic recession (or depression) that ran from 1929 to 1941. ...

Beside the dam itself there was also the necessary construction of two complexes of shipping locks and discharge sluices at both ends of the dike. The complex at Den Oever includes the Stevin lock (named after mathematician and engineer Simon Stevin) and three series of five sluices for discharging the IJsselmeer into the Wadden Sea; the other complex at Kornwerderzand is composed of the Lorentz locks (named after Hendrik Lorentz, the famous physicist, who personally did the calculations of the tides that were crucial to the construction of the afsluitdijk) and two series of five sluices, making a total of 25 discharge sluices. Periodically discharging the lake is necessary since it is continually fed by rivers and streams (most notably the IJssel river that gives its name to the lake) and polders draining their water into the IJsselmeer. Canal locks in England. ... A sluice is a water channel that is controlled at its head by a gate. ... A mathematician is a person whose area of study and research is mathematics. ... An engineer may be someone who practices the engineering profession, or the driver of a rail locomotive. ... Simon Stevin Simon Stevin (1548/49 – 1620) was a Belgian mathematician and engineer. ... The Wadden Sea (Wattenmeer in German, Waddenzee in Dutch, Waadsee in Frisian, Wattensee in Low Saxon, Vadehavet in Danish) is the name for a body of water and its associated coastal wetlands lying between a section of the coast of northwestern continental Europe and the North Sea. ... Painting of Hendrik Lorentz by Arnhemensis Hendrik Antoon Lorentz (July 18, 1853, Arnhem – February 4, 1928, Haarlem) was a Dutch physicist and the winner of the 1902 Nobel Prize in Physics for his work on electromagnetic radiation. ... The word physicist should not be confused with physician, which means medical doctor. ... Satellite image of the IJssel basin River IJssel, sometimes called Gelderse IJssel (Gelderland IJssel) to avoid confusion with its Holland counterpart, is a 120 km long branch of the Rhine in the Dutch provinces of Gelderland and Overijssel. ...

See also: Delta Works, Interliner. Oosterscheldekering In the North Sea Flood of 1953 a break in the dikes and seawalls in the Netherlands killed 1,835 people and forced the evacuation of 70,000 more. ... Interliner is an express bus system in the Netherlands. ...