The watermark column inside Amsterdam’s city hall is more than just a tourist attraction, it’s a reminder that the Dutch capital, like much of the rest of the Netherlands, is well below sea level.
Some 70 percent of the country’s economic output is generated below sea level, protected by a complex system of ancient dikes and modern cement barriers that hold back water from the sea and the multitude of rivers that weave through the country.
Now, with scientists predicting that sea levels will rise by about 1m this century, the Dutch are reversing centuries of tradition to create natural flood plains for rivers, as well as rebuild mangrove swamps as buffers against the sea.
“We’ve been adapting for 1,000 years. That’s nothing new. It’s just that climate change is going faster than it was before,” said Lennart Silvis, the operational manager of the public-private Netherlands Water Partnership.
Instead of raising dikes, the Dutch want to reclaim land and build public recreation areas that can absorb storm surges.
Rather than dredging sand to maintain beaches, they are looking at dumping piles of sand offshore to create “sand engines” shifted by the tides. Marshes may be renewed to break the power of incoming waves.
There is even a campaign called “Room for the River” that would weaken levees to recreate natural flood plains along rivers, including the Rhine and its tributaries, which flooded in 1995 following heavy rainfall that almost led to a calamity.
While the dikes can be shored up, as was done in 1995, preventing the country from being submerged in 6m of water, they could collapse if the sand and clay that form the barriers absorb too much water over time.
Hence the need for a long-term, solution given the possibility that the Netherlands will face sustained pressure from its rivers throughout this century as glaciers in Switzerland melt, raising the level of the Rhine.
River discharge in the country is expected to rise 12.5 percent in the coming years. This is on top of rising levels already seen in the past 10 to 12 years.
Those who work to promote such ideas say natural water buffers are a smarter move than building higher flood walls that may not stand the test of time as sea and river levels rise.
“One hundred billion [euros (US$144.4 billion)] spent on safety alone under uncertain conditions is maybe not the wisest investment,” said Raimond Hafkenscheid, director of the Co-operative Program on Water and Climate (CPWC) in The Hague.
Perhaps no country on Earth lives with rising seas in the way the Netherlands does. If its nationwide network of pumping stations failed, within a week the entire country would be under 1m of water.
From the age of four, virtually all children in the Netherlands start five years of swimming classes. They must eventually pass a test that includes swimming 100m while fully dressed in heavy winter clothing.
It may sound extreme, but for Dutch families that remember the great flood of 1953, which killed more than 1,800 people and wiped two villages off the map, it is a small price to pay for peace of mind.
That flood, the source of the high watermark at Amsterdam city hall, drove water levels 4.5m above normal.
“A city can’t be prepared for all the change that will come, but it can be flexible,” said Koen Olthuis, one of the principals of Waterstudio, a Rijswijk-based architecture firm that has designed floating structures around the world.
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