Dutch build sand dunes to fight rising seas
More than eighteen million cubic meters of sand are dredged from the bottom of the ocean and brought back to land to form new dunes; the new dunes — each 30 to 60 meters wide, and rising up to 10 meters above sea level — are built along a 20-kilometer stretch of the shore
On the beach at Monster, The Netherlands, bulldozers painstakingly turn sand dredged from the bottom of the North Sea bed into dunes in an ambitious effort to safeguard the Netherlands from flooding. Stretching more than fifteen miles southward from The Hague, the project is one of many in a never-ending battle against rising sea levels attributed to global warming.
“Because it is a low-lying delta, the Netherlands is very sensitive to climate change,” Water Management deputy minister Tineke Huizinga told AFP on a recent visit to the bustling work site.
“If sea and river levels rise, the Netherlands will be under threat,” Huizinga said, walking in yellow boots along a pipeline of several hundred meters (yards) spewing out dredged sand.”Fortunately, the coast is safe today, but we are investing in the security of people who will live here in 50 years.”
More than eighteen million cubic meters of sand — enough to fill 7,200 Olympic-sized swimming pools — are set to be poured onto the new coastal band of dunes until 2011.
The project got underway last year at a total cost of €130 million to the Dutch state.
Sand is dredged from the bottom of the North Sea, about fifteen kilometers from shore, by two specialized vessels that work in turns, day and night, before being relayed to the beach via the pipeline. Bulldozers then amass the sand to create the dunes, broaden the beach and gain territory from the sea, meter by meter.
“We had no choice but to extend the coast toward the sea,” the area’s flood prevention chief Michiel van Haersma Buma told AFP.”Our coast is relatively narrow. Houses and greenhouses lie just beyond the dunes. This area is so densely populated that we had no space to construct more dunes and dikes further inland.”
The new dunes — 30 to 60 meters wide, and rising up to 10 meters above sea level — are going up next to an existing band of dunes. Covering them is a special type of grass with long roots to keep the sand intact. “The more dunes there are, the less sea water can infiltrate,” thus reducing the danger of contamination of fresh water inland, Haersma Buma explained.
When completed, the project would have made the 20-kilometer stretch of dune-lined beach up to 200 meters wide at low tide, compared to 180 meters at present.
The economic stakes are high: Up to 65 percent of the Netherlands’ gross domestic product comes from areas that are located below sea level”We want to to be able to live and work in security,” Huizinga said. “It is a big investment. But the cost of protecting this area is a fraction of the cost that a flood would cause to the economy — and that does not even take into account the social disruption and loss of life.”
The government is due to unveil a new program next year for protecting the nation from water-related consequences of global warming, at a cost to the state of around one billion euros (1.5 billion dollars) per year from 2020, water ministry spokeswoman Marie-Christine Lanser-Reusken told AFP.
In September last year, a government-appointed commission warned that the Netherlands must spend more than €100 billion over the next century on dike upgrades and coastal expansion.
The Delta commission predicted a sea level rise of between 0.65 and 1.3 meters (2.15 and 4.3 feet) by 2100, and said about nine million of the country’s 16 million inhabitants already lived in areas directly shielded from the sea and rivers by dikes and dunes.
Floods in 1953 killed 1,835 people and left 72,000 homeless when a total 200,000 hectares of land in the southern provinces of Zealand, Noord Brabant, and Zuid-Holland were inundated.
