Dutch Reassess Water Defenses

With more than 1,000 years of experience building dikes, the Dutch have flood defenses few can match. But after seeing the devastation wrought by Hurricane Katrina, the government is reassessing what a worst-case scenario would mean for a nation where 10 million people live below sea level.

In a major report presented to parliament last week, the Traffic and Water ministry called for the Netherlands' biggest cities to review their evacuation plans and argued for a strengthening of river dikes, especially around Rotterdam.

"It's the opening salvo in what will be a long discussion," said ministry spokesman Hendrik Dek.

Reviews of water defenses go on all the time in a country whose very name means "the low-lying lands" and whose history has been determined by the struggle to reclaim safe ground from the delta of the Rhine and Maas rivers.

The Netherlands recently completed a 50-year program to upgrade its system of dikes and measures, spurred by a 1953 flood that killed 1,800 people.

Vowing such a catastrophe would never happen again, the Dutch built a massive system of dams, sea walls, and surge barriers to protect the south of the country against any storm save one so severe that statistically it is predicted to happen only once in
10,000 years.

Though the Delta Project gave the Dutch a measure of security, they were stunned by the scenes of confusion after the levees broke in New Orleans.

"Katrina shook everyone awake," Dek said. "A disaster like that always helps firm up the resolve to get things done."

Democratic Sen. Mary Landrieu of Louisiana plans to visit Holland next month to view the Delta Project, including engineering feats such as the Maeslantkering, twin rotating gates each the size of the Eiffel Tower that can seal the mouth of Rotterdam's harbor in case of a sea surge.

Dek said the levees in New Orleans had lower standards than Dutch law mandates and were built to withstand the kind of storm that could be expected once every 100 years.

"But we also must face the fact that no matter what you do to prepare, something can go wrong, defy all your models," he said.

Examples range from the effects of global warming or a terrorist attack to more prosaic problems such as erosion, design flaws, or burrowing animals.

Proposals submitted to parliament last week would, for the first time, link the investment in defenses to the potential economic damage if a dike were breached.

Studies found that the country could suffer $350 billion or more in damage if Rotterdam's river dikes were to fail.

The Dutch reserve more than $1.2 billion annually — around 1 percent of the national budget — to maintain and improve the dikes, dunes, pumps, sluices and windmills that work constantly to keep the country dry.

The current program operates on the principle of "living with water," an idea that could have implications for the rebuilding of New Orleans. Proponents say that building dikes and walls higher is a bad idea, because that will only worsen a disaster when it comes.

Instead, the Netherlands will work on contingency plans to deal with crises rather than just prevent them. One sparsely populated area near Nijmegen already has been designated for intentional flooding to drain water from the Rhine if the river rises too high.

In addition, efforts are being made to restore the country's natural drainage system by reconnecting minor creeks and canals to larger waterways — in effect, transforming the country into a giant sponge.

Rob van Doland, who designs weather models at the Royal Weather Institute, said the Netherlands may have to absorb 25 percent more rainwater as a result of climate change, and could expect a rise in sea level of up to three feet.

One solution would be designating additional overflow areas, he said.

"That would help us deal with extra water in the winter, and less in the summer," which current models predict, he said. "But so far that idea has not been enthusiastically received" by the government.

In a recent interview, Amsterdam Mayor Job Cohen said it was doubtful whether his city could realistically be evacuated.

"Look, I think something like that is always incredibly difficult," he said. "If you try to cart off a million people, that's naturally an enormous commotion and confusion — it would never go perfectly right. It's certainly not a case of, blow a whistle and, hey presto, you're high and dry."
By Toby Sterling