Polder - Polders and The Netherlands

Polders and The Netherlands

The Netherlands is frequently associated with polders. This is illustrated by the English saying: God created the world but the Dutch created Holland.

The Dutch have a long history of reclamation of marshes and fenland, resulting in some 3,000 polders nationwide. About half the total surface area of polders in north-west Europe is in the Netherlands. The first embankments in Europe were constructed in Roman times. The first polders were constructed in the 11th century. As a result of flooding disasters water boards called waterschap (when situated more inland) or hoogheemraadschap (near the sea, mainly used in Holland) were set up to maintain the integrity of the water defences around polders, maintain the waterways inside a polder and control the various water levels inside and outside the polder. Water bodies hold separate elections, levy taxes and function independently from other government bodies. Their function is basically unchanged even today. As such they are the oldest democratic institution in the country. The necessary cooperation between all ranks in maintaining polder integrity also gave its name to the Dutch version of third way politics - the Polder Model.

The 1953 flood disaster prompted a new approach to the design of dikes and other water-retaining structures, based on an acceptable probability of overflowing. Risk is defined as the product of probability and consequences. The damage in lives, property and rebuilding costs is offset against the cost of water defences. From these calculations follows an acceptable flood risk from the sea at 1 in 4,000–10,000 years, while it is 1 in 100–2,500 years for a river flood. The established policy forces the Dutch government to improve flood defences as new data on threat levels becomes available.

Some famous Dutch polders and the year they were laid dry are:

• Beemster (1609-1612)
• Haarlemmermeerpolder (1852)

As part of the Zuiderzee Works:

• Wieringermeerpolder (1930)
• Noordoostpolder (1942)
• Flevopolder (1956/1966)