The drought is not sparing anyone this summer: the Netherlands has been officially in “water shortage” since August 2nd, in this country where it is nevertheless very plentiful. Some buildings see their structures weakened: the state water authorities have carried out more checks on the dikes throughout the summer. While the large dikes facing the North Sea are relatively spared, the small structures that ensure water drainage and the drying out of the inland polders suffer particularly from the drought.
>> VIDEOS. Drought: lack of water endangers the operation of dams
These structures are usually made of peat, a traditional but fragile and unstable material. The black earth cracks as soon as the temperature rises too much, explains André Koelewijn, dyke specialist at the Deltares Institute in Delft: “When a crack forms, the peat dries up and oxidizes until it disappears. With global warming, the cracks are getting bigger and bigger. If the water suddenly rises, these cracks fill with water and the dyke can no longer withstand the pressure.”
Near the village of Pijnacker in the Delft region, a dike breach would mean flooding a polder measuring several hectares. The water from the drainage channel protected by the dike would flow to where Boss’s 90 cows quietly graze: “This polder, this whole area is three meters below sea level.”
“If the dikes give way, my cows will have to learn to swim. There will be no more farms here, it will be a lake!”
boss, dairy farmer
He continues: “I’m not worried because the Dutch have learned to live by the water level. And then the authorities who manage the water do a good job. They inspect the dikes, they check that everything is in order, to avoid flooding before the fall and winter break.”
So far only one dike has broken due to the drought in August 2003 near Utrecht. 1,500 people had to be evacuated. Jan, who lives a few kilometers away, also considers the problem almost secondary because it is under control. “It never happened. Ah! yes, once, in Wilnis.” No need to worry, assures Jan. “The dikes are constantly monitored all year round. Two-thirds of the country is below sea level, so we don’t have a choice.
The peat dikes are therefore regularly covered with a layer of clay to delay the appearance of cracking. And for several years, in the middle of summer, small boats have also come to spray the walls with water cannons.
Netherlands: Drought weakens levees in country obsessed with rising water levels – report by Jean-Jacques Héry