Dutch Engineers Reducing 1 in 10,000 Chance of Flooding to 1 in 100,000

"Before the Levees Break: A Plan to Save the Netherlands"
Wired (December 22, 2008)

"On a late fall afternoon on the western edge of the Netherlands, coastal engineer Marcel Stive stands atop a 40-foot dune. He stares out beyond the posse of wet-suit-clad surfers wading into the breakers of the North Sea. Where the surfers see inviting waves, Stive sees dry land—and a distant storm. He points south toward Rotterdam, Europe's busiest port. Arm outstretched, Stive rotates 180 degrees to face the shoreline running north. 'As far as you can see, in both directions, we're going to push the coast out 3, maybe 4, kilometers,' he says. 'We have to—to keep the water out.'...."

Engineers in the Netherlands are quite interested in making sure that the dry land in the country they made stays that way: dry. Particularly the part where Rotterdam is. That city, and the rest of the country that's below sea level, produces about 65% of Holland's GDP.

"...Yet the chance of a breach at Ter Heijde is actually quite low, about 1 in 10,000 in any given year. (In the lingo of storm protection, that's known as a 10,000-year flood.) The coastline and river deltas of the Netherlands are arguably the best-protected lowlands in the world, and the Dutch are a little miffed at Al Gore for suggesting in An Inconvenient Truth that their homeland is as vulnerable to rising seas as far less protected places like Bangladesh and Florida.

"To Stive and other sea-rise hawks, however, 1 in 10,000 has become too risky. They want to crank up defenses in some critical areas to the level of 1 in 100,000. 'To understand risk, you must consider the value of what would be lost,' says Stive...."

The article includes photos, a video, and maps: a fairly detailed look at a huge engineering project.