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The Netherlands is situated in a low delta close to the sea in which rivers like the Rhine and IJssel end. About 60% of the Netherlands lies below sea level, and from around the first century A.D. the history of our country is determinated by the struggle against the water. During a February storm in 1953 the south-western part of the Netherlands was struck by a catastrophic flood, in which 1853 people were drowned, more than 500,000 others left homeless and over 260,000 hectares (about 640,000 acres) of land was wasted. The Dutch population was devastated.

They firmly resolved to better protect their lowlands from the sea. Shortly after the disaster the Delta Plan was drawn up containing measures to prevent future disasters and in 1958 the Dutch started to construct a network of barriers, dikes, dams and locks, closing off the estuaries in the south-west.

The sea inlets in Zeeland were sealed off and with the completion of the Eastern Scheldt Barrier in 1986, the province of Zeeland was safe, but South Holland was not. Initially, the dike reinforcements there proceeded smoothly, but in the 1970s the people began to protest against the elevation of the dikes, especially in urban areas. Under the plans historic buildings would be lost in numerous places. Therefore, after much discussion, a movable storm surge barrier was opted for.

The Maeslantkering (Storm Surge Flood Barrier) near Hoek of Holland is the impressive final key-stone in the Delta Works and a striking beacon in the Nieuwe Waterweg. It has two closing doors that in case of stormtide can close off the entire 360 meters wide Nieuwe Waterweg in one move. These gates cannot, however, block the waterway when not in use as Rotterdam is a very busy port. But if there is an emergency situation, which is expected once in every ten years, the mouth of the river can be fully closed.

The flood barrier consists of two hollow semi-circular gates, each 210 m long, and attached by means of steel arms to a pivotal point on both river banks, where they reside in ‘normal’ weather. One door is almost as big as the Eiffel tower (which is 300 meters high) and in weight it is even four times as heavy. Never before in the world has a flood barrier been built with moving parts this big.

When in Rotterdam tides over 3.20 m NAP (Nieuw Amsterdams Peil = New Amsterdam Level - a standard the Dutch invented to know if you live under or above the inundation line) are expected, the barrier closes automatically. Seawater is let into the parking docks, causing the hollow gates to float. They are turned into the river, and after having met in the middle, the compartments in the doors are flooded and the huge gates are sunk on a threshold on the bottom of the river.

As soon as the high tide is over, the water is pumped out of the doors, the whole construction starts floating again and, when it is anticipated that the next high tide will not rise above the set limit, returns to the parking docks. This whole process is fully automated: even the final decision to close the barrier is made by a computer.

Just a few examples to further wet your appetite.

• the length of the lattice arms is equal to the height of the Eiffel Tower (or a seven-storey apartment building) and contains twice the steel that's in that tower.

• it takes half a swimming pool of paint (30,000 ten-litre tubs) to paint the Maeslant Barrier.

• each parking dock, which houses a barrier wall when not closed, is as big as four Olympic swimming pools.