Database

Despite the many floods throughout Dutch history, and the presence of thousands of kilometres of dikes in theĀ landscape, there has not yet been any detailed description of the location of all the dikes on the scale of the Netherlands, and there has been no comprehensive overview of the different types of dikes. The research behind the book Dutch Dikes now fills that gap. The result is a geographic database containing all the dikes of the Netherlands: flood defences and non-flood defence dikes.

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Structure of the Dutch Dike network

The Netherlands’ dike network extends for over 22,000 kilometres (including dikes that do not serve as flood defences), while the Dutch coastline measures a mere 880 kilometres. Why are these thousands of kilometres of dikes so essential to the Netherlands? The best way of classifying the dike network is on the basis of flood defences: some dikes serve to prevent flooding while others do not, or no longer have that function.

However, regardless of this distinction, the map makes one thing clear at a glance: a dense, extensive network of dikes covers more than half of the country. In some areas, it is so dense that those living in the vicinity must necessarily have close ties with it, whether consciously or not. For the Dutch, dikes are simply part of life.

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Detailed dike map
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Primary flood defence dikes

Cohesion of the Dutch Dike network

Dikes are man-made structures that defend against natural forces like water, climate and altitude and are mostly constructed of material found on site. Over the centuries, the Netherlands had frequently been flooding, from the rivers as well as the sea in varying degrees and severity. Although the Netherlands is well protected from the water by the dike defence system today, there is always a risk of flooding. To get an overview and an understanding of the Dutch safety situation a series of maps is created in which the dike network is projected on different GIS information.

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Floodings over the centuries in the Netherlands with the disappeared settlements by floods (dots).
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Flood-prone Areas (flood depth in gray, build area in red and industrial areas in blue)