Hurricane Katrina: The Aftermath
Changing Course to Go With the Flow
The future of the city of New Orleans will depend on its ability to keep its citizens' heads above water. On the other side of the Atlantic, the same applies to the future not just of a city but of a whole country -- the Netherlands, where more than 60 percent of the population lives below sea level. After their dikes failed half a century ago, leading to a catastrophe eerily similar to the one in Louisiana, the Dutch launched an ambitious scheme to build better defenses; after further flooding along the country's rivers, as recently as 1995, they decided on a more radical approach -- to revise their strategies toward water.
Having battled rivers and the sea for centuries by building bigger dikes, the Dutch have decided to work with nature instead of against it. It's a philosophical shift that is evident in the way people in the Netherlands discuss the fluid challenge they face: While Americans have been talking about keeping water out of New Orleans, the Dutch in recent years have been talking about making ruimte voor water , "room for water," and "building with nature."
Every Dutch citizen who is old enough has a story to tell about the storm surge that burst through poorly maintained dikes 52 years ago, killing nearly 2,000 people. The Misery of 1953 is remembered alongside the storms of other centuries -- the St. Elizabeth flood of 1421, the All Saints' Day flood of 1570. And it prompted titanic works of hydraulic engineering, which the American Society of Civil Engineers counts -- alongside San Francisco's Golden Gate Bridge and Toronto's CN Tower -- among the Seven Wonders of the Modern World. But more importantly, the great flood of Holland's delta region began a process that has led the world's most water-weary people to reevaluate its age-old war on water and reach a kind of truce. "We now realize we cannot cope with these problems if we continue to fight against the water," Jeroen van der Sommen, managing director of the independent Netherlands Water Partnership, told me last week. "For now, maybe yes. In the long run, no. We are trying to imagine new kinds of protection."
The American disaster has reinvigorated the ongoing Dutch debate about how to manage the country's old foe, and where the weaknesses in its defenses (and evacuation plans) lie. It has also reminded people of the danger of complacency -- that new kinds of protection may have been just what was missing in New Orleans, crouched as that city has long been behind its own poorly maintained levees in a river delta similar to the Rhine's.
Van der Sommen, whose organization coordinates Dutch water expertise, does not mean to suggest that the old kinds of protection should go the way of windmills and wooden shoes. Far from it. Without the dikes and the dams, the levees and the locks, both Rotterdam and New Orleans would long ago have been inundated. Some of the Dutch dikes built since the 1950s tower as much 40 feet above the roiling deep -- twice as high as New Orleans's tallest levees.
But what the Dutch have been trying to do more recently is strengthen these "hard" protections with "soft" ones -- reinforcing concrete with swamps and sand. They are focusing attention on the kind of fragile coastal landscape that Louisiana has steadily been losing -- maintaining dunes and mud flats, protecting salt marshes and barrier islands as well as creating artificial reefs to act as buffers against the waves' relentless pounding.
The goal is no longer to control nature. "Resilience is the aim," says a Dutch report titled "Water, Climate and Risk Management" put out by a core group of institutions that specialize in hydrology. "And it is thought this can partly be achieved by encouraging the natural transportation of sand by water and wind." In some coastal areas, sand has been imported to reclaim land where breakwaters jut out into the sea, and then it's been left to nature to do the rest. At the Hook of Holland, such natural building techniques have created beaches and a wildlife habitat as well as added protection for the land.
These strategies are made all the more urgent by climate change, which, estimates suggest, will cause the sea level to rise anywhere from a few inches to several feet over the next century. Add to that the increased runoff from the rivers that traverse the country and you can see why the Dutch are trying to go with the flow: If you want to keep your head above water, you have to be prepared to get your feet wet.
"God created the Earth, but the Dutch created the Netherlands," is the patriotic adage passed down through generations of a people who have long entrusted their lives and livelihoods to the lowlands. The Dutch have been pushing back the North Sea for hundreds of years, first building farms and villages on terps, or little mounds, and then connecting them with elevated earthen walls. In the 13th century, windmill technology allowed water to be pumped out of areas below sea level, creating the Netherlands' famous reclaimed land, or polders.
But with nature always ready to mount a fiercer invasion, the Dutch have needed more and more imposing structures to restrain the water. Few are more impressive than the barrier dam, or afsluitdijk , built between 1927 and 1932 across the mouth of the tidal estuary known as the Zuiderzee to prevent the North Sea from sweeping in and swamping coastal communities, as it had done in 1916.
I can remember the first time I crossed that dam on the A7 highway from North Holland to the province of Friesland -- at high speed on the back of a motorbike, with a brackish wind blowing in from the sea over the embankment to our left and a vast expanse of glassy fresh water stretching off to our right. Dead straight, almost 20 miles long and 100 yards wide at its waterline, the massive seawall is a source of understandable national pride because of the protection it has afforded for almost a century. But it is the kind of unyielding, ecologically challenging barrier that is becoming increasingly rare in the Netherlands these days.
The afsluitdijk turned the salt-water Zuider sea into the freshwater Ijssel lake, altering the region's ecosystem and depriving the estuary's fishermen of their traditional catch (although the lake has since become a renowned wildlife refuge). And, like any other solid dike or dam, the afsluitdijk created a new set of water problems. Closing off the tidal estuary meant, for example, that there would be less coastline to absorb the daily rise of North Sea tides, intensifying the risk of erosion and flooding along the open coast outside the dam. The dikes along those coasts would have to be raised. But by how much? Estimates ranged widely, from about one to 12 feet until Dutch physicist Hendrik Lorentz did the calculations crucial to the dam's construction -- an early example of the complex mathematical modeling that characterizes modern water management in the Netherlands.