Dutch polders gave the country its oldest democracies and a style of politics
Around a fifth of the Netherlands was once under the sea. Keeping that reclaimed land dry demanded constant cooperation, and the water boards set up to manage it became the country's oldest democratic institutions, with their own elections and taxes. The same spirit of compromise even lent its name to the Dutch Polder Model.
A polder is a patch of low ground enclosed by dikes so that it functions as its own artificial water system. It can be land won from a lake or seabed, a flood plain walled off from a river or the sea, or a marsh cut off and drained, which Germans often call a koog. The word descends from Old Dutch polra, built on a root for a piece of raised land, and it has been borrowed into thirty-six languages.
Polders never stop fighting water. Drained marsh subsides, and peat soils shrink further as they decompose on contact with air, so every polder eventually sits below the water around it at least some of the time. Rain, groundwater pressure, rivers and canals keep adding water, which must be pumped out or released through sluices at low tide. Dikes carry their own weaknesses: sand can collapse when saturated, dry peat may be too light to hold water back, and burrowing muskrats are hunted in parts of Europe because their tunnels let water in.
The Dutch built their first polders in the 11th century; the oldest still in existence, Achtermeer, dates from 1533. Today there are some 3,000, and by 1961 roughly 18,000 square kilometres, about half the country, had been reclaimed from the sea. Beemster and Flevopolder are among the best-known projects. A popular saying credits God with making the world and the Dutch with making their own country. Bangladesh, Belgium, Canada and China have polders too.
The catastrophic flood of 1953 transformed Dutch thinking. Engineers began designing defences around acceptable risk, weighing potential loss of life and property against the cost of protection. The resulting standards aim to limit sea flooding to once in 4,000 to 10,000 years, and river flooding to once in 100 to 2,500 years. Flooding polders has also served as a weapon: in World War I, the Allies turned the land along the Yser River into impassable swamp to halt the German army.
Source: Polder
