As NOLA braces for Hurricane Rita’s rains, praying its damaged levees will hold — and Rita’s rank has been upgraded from fifth to third place as the most powerful storm in history — it’s still important to look ahead to possible solutions. Tomorrow’s Wall Street Journal (sub.only) critiques “supersizing the levees,” declaring:
“Protecting New Orleans from future hurricanes will cost billions … “send swarms of bulldozers into swank neighborhoods (PHOTO above),” blocking views … “threaten environmentally vulnerable marshes, and trigger lawsuits from homeowners whose property would have to be seized to make room for the supersize levees.”
The WSJ’s companion piece, “Other Ways to Deter Floods,” lists a number of alternatives to earthen levees — some realistic, some not … from gates to bladders … details BELOW:
Earthen levees aren’t the only way to hold back water. Here are some alternatives proposed or already in use in other countries:
Barriers: After a 1953 flood killed nearly 1,900 people, the Netherlands embarked on a 40-year, $8 billion project called Delta Works, a network of sluices, dams, levees and barriers. One of its most ambitious projects is the Maeslant barrier, an enormous moveable sea wall completed in 1997 to protect the port of Rotterdam. When a computer model predicts a dangerous storm surge, the barrier, which is operated by two arms nearly the size of the Eiffel Tower, can close off the North Sea from the main shipping lane into Rotterdam. So far, the barrier, which sits 10 feet higher than sea level, hasn’t been needed.
Gates: After years of political and environmental debate, Italy is installing a system of gates on the bottom of the Adriatic Sea to keep out rising tide and prevent Venice from flooding. The panels are to be filled with air to make them rise. Engineers say they would be impractical on the Gulf of Mexico, however, because so many would be required and because they are designed to hold back additional water from high tides, not walls of water from hurricanes.
Bladders: Some vendors sell tubes encased in a hard plastic shell that can be filled with water, even floodwater, and used to hold back a storm surge. These devices work best, floodplain managers say, as temporary measures to protect individual buildings or to dam off small bodies of water.
Geogrids: Some engineers favor expanding existing levees with a type of super dirt, reinforced with a synthetic polymer made of a petroleum byproduct. These “geogrids” create a strengthened soil that has been used to build roads on weak ground and retaining walls.
Smart concrete: Other engineers propose coating earthen levees with a protective, two-foot shell of concrete with the ability to sense when a breach or other structural damage occurs. Such “smart concrete” contains electronically conductive carbon fibers that can measure stress from a remote location.
I say turn New Orleans into a research venture. If we’re ever going to colonize the Moon (or harsher environments) we’re going to need more efficient technology than levees or other barriers.
My NOLA proposal? Let NASA take over FEMA.
Behold, the NEW New Orleans.
</half-snark>
(img stolen from here)
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The disasters cannot be compared as the situation is quite different. The damage to the Dutch dikes, 115 miles destroyed and an area of 380,000 acres were inundated . Mostly agricultural land with a number of towns, villages and cities with harbors of fishing based communities. The Dutch have lived with storms and dikes for centuries, the storm watch was in place but the storm was no match for the limited dikes.
Similar to the damage done by Katrina hurricane, the authorities were warned for poor funding to have the dikes restored and meet the expected fury of a storm once in fifty years, that would flood the land.
click on map for animation storm surgeNorth Sea coastline in 1953
The consequences of the storm were disastrous: 1835 persons drowned, and some 20,000 cows, 1,750 horses and 12,000 pigs perished in the waves. Houses, schools, churches and other buildings: 47,300 damaged of which 10,000 irreparable. A length of 115 miles of dikes were destroyed or severely damaged by the power of the storm and waves resulting in flooding of 153,000 hectares (380,000 acres).
A total of 72,000 persons were evacuated, therefore 1:40 were killed in the storm, approx. 2,5% of the population.
Flood Disaster – February 1, 1953
<click on pic to enlarge>
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Sea, tides and sand dunes
A resistance, determination to exist and fight the elements of nature.
but the Dutch created the Netherlands.”
American tourists do feel a bit uncomfortable in their approach to Amsterdam Airport: “Welcome ladies and gentlemen. We’ll shortly be landing at Schiphol Airport, 15 feet below sea level.”
The Dutch do fear the onslaught of rising sea level as predicted by global warming and the melting glaciers. But after the 1953 spring tide storm disaster in their southern province of Zeeland, the Dutch rebuild all their dikes to a higher level and the immense structures to withstand all storms for a thousand years, statistically.
The design of dikes has been unchanged for centuries, and only recently has seen a first failure of a sliding dike, due to … drought! The Dutch design of dikes can also be witnessed in France, Normandy, from centuries ago.
Emblem of Zeeland ProvinceCoastal Guide to the Netherlands
World Atlas
To battle the rising tide – a political lesson from the Dutch: resistance, determination and invest in a plan.
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Oui, what a marvelous post!
Thank you so much.
However different the situations, do you think we in the U.S. should call on Dutch experts to help us figure out what to do?
(One of our chief problems is the destruction of wetlands. .. how is that handled/ preserved in The Netherlands?)
I heard somewhere on cable news, that our core of engineers fromNOLA, helped the Dutch to design theirs, it may have been in Mary Landrieus speech in congress, post Katrina…So if we helped them, and couldn’t do it here, well then?????Or was is the money was never there to do the job, puzzels, puzzels…..
Are there wet lands on all coasts, don’t think so but I am sure Oui will tell me…Here is socal, we still have some marshes, but one big marsh was drained decades ago to create a town there and they would be wiped out now in a tsunami or tidal surge like in Katrina. We rarely have hurricanes here, but with the changing weather patterns, that may be in store.
Swamps are natural buffers against flooding. We’ve begun to appreciate their value, so now we call them wetlands.
Paved spaces flood quickly and drain quickly. Unpaved spaces flood slowly and drain slowly, typically with far lower peaks.
One of the problems with regional development in New Orleans, and it isn’t really to be faulted because no place does a good job of it, is that development driven by very local zoning decisions was allowed to fill in wetlands and unpaved space that could have buffered surges of water around the city.
While New Orleans doesn’t need to be abandoned, and doesn’t need to be put under a dome, it could use some large central park sized parks or greenbelt, in low lying areas most at risk of flooding. One commentator on NPR today suggested converting a lot of NO which is currently one story to two story construction in similar styles, which would free up space for this kind of change.
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After a catastrophic 1953 flood,the Dutch built an elaborate
flood-control system. ABC News
The flood led to dramatic changes. The Netherlands spent $8 billion over 30 years fortifying the coastline with a sophisticated system of dikes, dams and levees.
Dutch law now requires that coastal defenses protect against the worst storm imaginable.
Ted Sluiter, a spokesman for Waterland Neeltje Jans, a recreational park and information center set up at the base of a major dam, said the hydraulic sea wall that is considered the crown jewel of the system would protect the country against all but a biblical flood. The dam is constructed in a way that protects the region’s wetlands, environmental-sensitive areas that serve as natural storm buffers.
“Without those, Holland will just disappear,” Sluiter said. “So, it has to be a Dutch discipline, hydraulic engineering.”
The hydraulic sea wall is 130 feet high and nearly six miles long. It’s basically a giant steel curtain that can be opened or closed, depending on the water level. One dam alone took more than a decade to build.
Down the North Sea coast, there’s a giant door that can seal off shipping lanes in an emergency. Each arm is as long as the Eiffel Tower and twice as heavy. A computer is programmed to close the door as soon as the water rises 6 feet.
The Dutch system is at least 50 times stronger than the coastal defenses surrounding New Orleans. “To the Dutch standards, New Orleans was not very well-protected,” said Huib de Vriend, director of Delta Hydraulics, a company that puts together the heavy machinery involved in some of the flood-control projects.
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