Netherlands Enlists Nature to Sway the Seas

Half a century ago, a mighty North Sea storm smashed into the Netherlands with deadly devastation, spurring the Dutch to build their famous dikes even higher.

Today, the country is rethinking flood control to face a less dramatic but more far-reaching threat -- climate change.

More than 1,800 people died in February 1953 when waves whipped up by fierce winds and riding a spring tide breached ancient dikes and washed deep inland. It was such a tragedy in this small country that it has always been known simply as “the flood.”

Afterward, the Dutch began a massive construction program, building new dams and raising the dikes that have shaped the coastline and the history of this rain-soaked country where the Rhine and Maas rivers empty into the North Sea -- and where two-thirds of the people live below sea level.

Now, faced with the threat of climate change and global warming, the Dutch have an entirely different plan of defense against rising seas and increasingly common torrential rain.

The 21st-century objective is to learn to get along with the water, rather than try to tame it.

On the coast, engineers will dump sand onto the beach or just offshore, harnessing the natural power of waves to mold the sand over time into new protective dunes. The technique will slowly replace the coastal dikes -- tall, uniform embankments -- that the Dutch have been building since 500 B.C.

The Rhine and Maas rivers will be broadened in spots. Rather than raising the banks against overflow, vulnerable areas will be cleared of buildings and people to allow “room for the river.” And to deal with a worst-case scenario, plans have been drawn up to bulldoze holes in some dikes in sparsely populated farmland, so rising waters could pour in and lessen flood dangers elsewhere.

“You can’t make agreements with nature,” said Bert Keijts, head of the government’s water department. “You can build the dikes higher, but at a certain moment, the ground is too weak to support them. And if you only build higher, the moment it breaks, you have a worse catastrophe.”

Unlike the U.S. government, which doubts whether policy changes are needed to defend against global warming, the Dutch are taking action in expectation of a two-foot rise in sea level and a 20% to 30% increase in average rainfall.

Roughly $5 billion has been budgeted over the next 15 years for improvements on the Rhine, the Maas and the coastline.

“If you wait 50 years, until you’re certain, then you’ll be too late,” said Gunther Konnen of the Dutch royal weather institute.

Konnen said observations fit with current models of climate change, pointing to floods along the Maas in 1993 and again in 1995. The country had another near-miss on the Maas in early January.

The new thinking began in 1987 when the Dutch built a nearly 2-mile-long removable dam across the East Schelde waterway, at the mouth of the open sea, near the city of Middelburg.

The unique structure, which sits atop concrete pillars in 132-foot-deep water, allows seawater and fish to flow freely with normal tides.

But when a storm threatens, massive steel plates drop into the sea, transforming a bridge into a solid wall.

It was an engineering marvel. With powerful tidal surges rushing back and forth, 66 pillars weighing up to 17,000 tons each were lowered into place with pinpoint accuracy at the precise moment the sea changed direction.

Construction of the East Schelde Flood Barrier capped a furious decade-long debate between environmentalists and flood-control experts.

“That was the pivotal moment in thinking, when the Netherlands said, ‘Things have to be built, but you must also reckon with other interests,’ ” said Walter van der Kleij, head of the Dutch corps of water engineers.

“That kind of thinking is still continuing,” he said. “We shouldn’t lay dams in front of the coast. We shouldn’t dump asphalt on the dunes. No, we should build with nature.”