What the Dutch did to save themselves after the flood of 1953
By SIMON ROZENDAAL*
(7 September 2005) -- MANY DUTCH, shocked by seeing the devastation caused in the US by Hurricane Katrina, were reminded of what happened to their own country more than 50 years ago. On 1 February 1953, the southwestern part of the Netherlands was struck by a flood of biblical proportions. The Dutch levee system collapsed in 500 places. There was nowhere to hide. More than 1,800 people drowned, together with tens of thousands of cattle and other animals. Some 4,000 houses were destroyed, and 40,000 severely damaged. About 100,000 people had to evacuate out of a population of around 12 million.
The Dutch had suffered catastrophic floods before, but the deluge of 1953 was a different kind. Just consider that twice as many people were killed in the flood as during the infamous German bombing of Rotterdam in 1940. The nation was stunned. Older Dutch from the southwestern islands still get tears in their eyes when they talk about how they lost loved ones during what is simply called "the disaster."
The Dutch reaction was: Never Again. The government decided to give the southwestern and most vulnerable part of the country the best possible protection. Eleven massive dams, sea walls and sluices were created in waters that sometimes look more like a sea than a river. The hydraulic wall built in the vast Oosterschelde, for instance, is 5.6 miles long and rests on 65 concrete pillars about 43 yards tall. Its sluice-gate doors are usually open to protect the special habitat (partly seawater, partly freshwater) behind it, and are only closed when floods are imminent.
Another wall, the Maeslantbarrier that completed the protection system, consists of two hollow doors -- as long as the Eiffel Tower in Paris is tall, and four times as heavy -- which are lying in docks on the banks of the Nieuwe Waterweg. In the event of extreme bad weather the docks are filled with water, and the gates float and are turned into the Nieuwe Waterweg where they seal off the river. In that way this barrier protects the city of Rotterdam and its surroundings, where about the same number of people live as did in greater New Orleans.
This complex system of dams and barriers -- called the Delta plan -- is a technological achievement comparable maybe in its complexity and ambition to the American Apollo project that put a man on the moon. After all, the Delta plan was designed to protect the Netherlands from flood conditions that happen only once every 10,000 years! New Orleans, on the other hand, was protected only against hurricanes that occur every 50 years. The total cost of the Delta plan, which began in 1953 and was only completed a couple of years ago, amounted to $5 billion....
*Simon Rozendaal is the science writer for Elsevier, a Dutch weekly newsmagazine.
Source: Wall Street Journal
Questioning the 'Dutch Solution'
Martin Enserink and John Bohannon
KRAGGENBURG, THE NETHERLANDS (16 September 2005) -- DUTCH scientists are making waves -- literally. In a hangar here, researchers from Delft Hydraulics, a research and consulting institute, have built a 4-meter-wide slice of a dike at the end of a basin, used to mimic the North Sea crashing into the coast. Their goal: to test how different types of surface materials weather the thunderous onslaught.
Even after a millennium of hard-won experience, the Dutch are still perfecting the art of dike construction. They have little choice. More than half of the country -- including Amsterdam, Rotterdam, and most of The Hague -- lies below sea level and continues to sink, and the water is expected to rise as a result of climate change. Three major, often erratic, rivers compound the challenge. No wonder that many in the United States are wondering if the Dutch experience holds lessons for New Orleans.
Safety first. The Delta Works, a response to the 1953 flood in the Netherlands, consists of a series of dams including a storm surge barrier across the Eastern Scheldt (pictured). CREDITS (LEFT TO RIGHT): K. BUCKHEIT/SCIENCE; DELFT UNIVERSITY OF TECHNOLOGY
Scientists in both countries agree that some of the technology developed here could be useful, and Dutch institutes and businesses are eager to help. But their offers come at a time when Dutch water management is increasingly questioned at home. Some scientists say the reliance on engineering prowess is not only ecologically harmful but has increased vulnerability in the long run. The national mindset shouldn't be exported without awareness of its downsides, cautions Toine Smits, a water management expert and professor at two universities.
The Dutch, too, learned their lessons the hard way. On 1 February 1953, a severe North Sea storm combined with a spring tide burst through neglected dikes in hundreds of places, killing more than 1800 people and flooding 2000 km2 in the southwestern provinces. The answer, built over the subsequent 45 years, was The Delta Works, a series of dikes, dams, and other structures that closed off the major sea arms in the southwestern delta -- destroying entire ecosystems in the process -- and shortened the coastline by 600 kilometers. Dikes that protect the most densely populated areas of the country are built to withstand all but storms expected once every 10,000 years, says Delft Hydraulics director Huib de Vriend.
Louisiana's geography is different, and no one is talking about damming the Mississippi Delta. Still, some Dutch solutions may work, says Bruce Good of the U.S. Geological Survey. After an intense political battle, for instance, the Dutch decided against permanently closing off one estuary; instead, the Eastern Scheldt was equipped with a "storm surge barrier" that shuts only in emergencies. Although pricey -- the project cost more than $1 billion -- a similar solution could be used to block Lake Pontchartrain from the Gulf of Mexico while saving its ecology.
But in the end, protecting low-lying areas with dikes only is a "dead-end street" that should be avoided if possible, says Henk Saeijs, a former civil servant and professor at Erasmus University Rotterdam. When natural sedimentation stops and groundwater levels are kept low, the land sinks, requiring ever higher dikes and bigger pumps to get the water out. ("Pumping or drowning" is a national motto here.) Meanwhile, the illusion of safety lures people and investments, making future floods even more costly.
Although there is no turning back for built-up areas, it's "utterly crazy" to keep urbanizing areas far below sea level, as is still happening in the Netherlands, Saeijs says. Instead, he advocates "embracing the water" -- an approach in which floods are not a major problem because people live on mounds, in higher areas, or "floating cities."
But Han Vrijling, a hydraulics engineer at Delft Technical University, says that in most cases, giving the water its freedom is a "romantic" notion that's not compatible with a modern economy. Besides, "we shouldn't be too nervous" about ever-higher dikes towering over a sinking country, he says.
Soure: Science, Vol 309, Issue 5742, 1809, 16 September 2005
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