CBSNews.com: “Great Wall of Louisiana” Debated
With a price tag of $886 million, 65 percent of which would be federal money … a bold plan put forward by the U.S. Army Corps of Engineers ” and currently being discussed in the new Congress ” would build a semipermeable “Great Wall of Louisiana” from the Mississippi River to Texas to block the advancing Gulf … In the mayhem of a storm, nine 56-foot-wide gates and three even larger floodgates would close to keep out tidal surges, but on calm days the locks would open and allow the region’s natural intertidal flows to nourish the marshes.
Those for: “For some 120,000 people along Louisiana’s blue-collar coast, the ‘Morganza-to-the-Gulf’ levee ” a sort of intertidal Maginot Line ” is seen as salvation, especially since the 2005 storms.”
Those against: “… such a ‘leaky levee’ is a false hope, a taxpayer-funded Louisiana hay wagon that is scientifically unproven and even detrimental to both the region’s ecology and economy.”
Concerns:
a) Bayou Sauvage NWR is the only place such a wall has been tested, and with limited success.
b) What about fluvial deposits from rivers draining into the Gulf of Mexico that create coastland?
c) No wall can save the coastline from global sea level rise
“The short-term push for this is enormous, probably irresistible. But it’s folly,” says Oliver Houck, an environmental resources lawyer at Tulane in New Orleans. “The best thing you can say about it is we’re taking a $4 [billion] or $5 billion gamble on a theory that’s already proven not to work.”
In support of the Great Wall, Representative Charlie Melancon (D-La) cites the Big Dig: “You go up to Boston where they spent $15 billion on a tunnel ” that’s a want, not a need.”
Bad example, Charlie. I don’t think this is what Boston wants or needs.
If this idea goes ahead there will be a lot of rich(er) pols.
Options? Stay or leave.
If we stay, remember that New Orleans and the surrounding area are in most parts already below sea level and sinking. Unless you figure out a way to raise the city, we must have significant levees to protect us.
I know there’s been a lot of chatter about building marsh to protect us, but it is probably less feasible than buidling huge levees. Look it up and look at a map. The best guess we have is that one mile of marsh will knock down about 3 inches of storm surge. How much marsh will it take to reduce a Katrina-monster storm surge of 30 feet to the current levee height of 18 feet? Draw a line on map and see how totally impractical that is–for starters, we’d have to fill Lake Borgne!
So I say build the levees. And where should those levees be? As far away from the populated areas as possible. We want there to be ponding and storage areas so that if a levee is overtopped or breached, we have a fighting chance of surviving. When the levees are right next to the houses…well, we’ve seen what happens if the levees are less than perfect.
The environmentalists are calling it the Great Wall of Louisiana as an insult, but I love the sound of that name. I’d be more than happy to have a wall of protection that stands for a thousand years!
Peace,
Tim