US Army Corps can't stop floods in New Orleans

Lt. General Robert Van Antwerp, Chief of the US Army Corps of Engineers would not answer my question "Should New Orleans be abandoned?"

But the General, whose job it is to protect New Orleans from future hurricanes, did admit he could not save the city from storm surges. "Protect the city no, reduce the risk yes. We can develop better early warning systems, better evacuation plans, better levees to hold back most of the water but we cannot stop levees being overtopped and the city flooded."

Evacuation and retreat from the sea in Louisiana is the central question concerning the Corps and the rest of the delegates attending the Religion, Science and Environment Symposium in New Orleans.

How to save not just the city but the southern half of Louisiana from the combined effects of man's past mismanagement, subsidence of the delta, and ever increasing sea level rise?

The Mississippi Delta sinks around an inch every 30 months and with sea level rise accelerating water levels across the delta will increase six feet this century. With much of the delta less than three feet above sea level most communities will be drowned by 2050, leaving New Orleans, if it survives at all, a vulnerable island behind its levees.

Man's share in the destruction has been mainly the oil and gas industry's massive canal network. Canals cut through the fresh water swamps and marshes allowing vast quantities of sea water from the Gulf to wash into the delta killing many of the trees, plants and animals that protected the land from storm surges. This is the way America gets 35% of its gas and oil.

The figures of losses in the delta are startling. Chris Macaluso in charge of the newly created Office of Coastal Protection says 2,300 square miles of marsh and swamp have been lost because of salt water intrusion in 50 years. In the four-month hurricane season land disappears at the rate of an acre every six minutes or 25 to 40 square miles a year.

His office is reconstructing some of the barrier islands along the Gulf to protect the remaining wetlands from wave action but what used to be marshland behind them is now open water dotted with oil wells criss-crossed with pipelines. Most of the once vibrant Cyprus forests, which could stop the storm surges, are reduced to dead stumps sticking out of the water.

"We have broken the eco-system. What we are doing to restore it is a drop in the ocean of what is needed." His office is spending $1.5 billion over four years on wetland restoration. Another £14.3 billion is being spent on new levees and defences for New Orleans. Estimates of what it would cost to save the delta's wetlands and its settlements from sinking are estimated at $200 billion in the state governor Kathleen Babineaux Blanco's "Louisiana's Comprehensive Master Plan for a Sustainable Coast."

This calls for the diversion of the Mississippi, basically breaching the levees that keep the river flowing to the Gulf, so that the sediment spreads over the delta and heals the eco-system by allowing it to re-grow.

To allow river diversions the Corp of Engineers needs to modify its main priority which has been to keep the Mississippi open to navigation at all times. The river carries 11% of the America's trade, with New Orleans as the country's largest port, and is vital to the nation's economic welfare.

The river would have broken out of its existing channel decades ago if not held in a straightjacket by the Corps. Lt General Van Antwerp was candid. "We are having to rethink everything. But even if we get it right, and that is no means certain, there has to be the political will to vote the money - and that is beyond my brief."

If the Corps gets it wrong, or the vast sums of money required are not provided, then the Gulf will move inland and eventually the river will break out. Where will New Orleans and the oil industry be then?

 

Comments

[maxfax]

The head of the ASCOE was irresponsible, still awaiting the responsible from the Louisiana delegation. Anyone?

http://www.wwltv.com/topstories/stories/wwl102609tpcorps.2563d9639.html

[Bienville]

I am always disapointed to hear "We can't do something.­"

Very early in my career, an very seasoned engineer told me that nothing is impossible, it's just a matter of money.

Since money is beyond General Antwerp's brief, I cannot see how he can make the pronouncement that New Orleans cannot be protected.

I believe that New Orleans can be protected. It is just a matter of money.

[maxfax]

What's that noise I hear from the Louisiana delegation?

*crickets*

[noneIn2008]

In the 1950's the Corp already acknowledged that New Orleans should be abandoned and the Mississippi was going to change channels. Our always wise Congress voted they were to stop nature. You will not stop nature, only slow the progression. Vote all you want, demand all you want, Mother Nature will have her way.

[Bienville]

We beat "Mother Nature" all the time.

We've been beating nature for at least 10,000 years. We have airplanes, automobiles, telephones, television, internet..­. We drink water that comes from holes in our walls. We eat food grown on distant continents. Men have walked on the Moon.

Sure, if we do nothing, the forces of nature will degrade all our systems, she degrades her own systems. Nature never sleeps. If we remain active and vigilant, we can always overcome nature.

BTW, it was man's activity, not nature's, that started the River down the Atchafalaya channel. Where did the Corps say New Orleans should be abandoned.

[research]

Nothing natural about New Orleans subsidence, it was caused by sucking water, oil and gas out of the ground.

The Water wells exists, though unused.

Pump fresh river water down them and refill the aquifer, you should be able to raise New Oleans 15-25 feet in less than 10 ten years.

[Bienville]

Where did you get this data? There are certainly many oil and gas wells in southern Louisiana, but water wells? The River delivers an astonishing volume of fresh water to the area. Water wells hardly seem necessary. I have read about the effect of pumping oil and gas from the ground - not truly subsidence, but I forget the technical term - and it is reckoned to be on the order of 10-20% of your figure.

[research]

"Subsidence
Main article: Groundwater-related subsidence

In its natural equilibrium state, the hydraulic pressure of groundwater in the pore spaces of the aquifer and the aquitard supports some of the weight of the overlying sediments. When groundwater is removed from aquifers by excessive pumping, pore pressures in the aquifer drop and compression of the aquifer may occur. This compression may be partially recoverable if pressures rebound, but much of it is not. When the aquifer gets compressed it may cause land subsidence, a drop in the ground surface. The city of New Orleans, Louisiana, is actually below sea level today, and its subsidence is partly caused by removal of groundwater from the various aquifer/aquitard systems beneath it. In the first half of the 20th century, the city of San Jose, California, dropped 13 feet from land subsidence caused by overpumping; this subsidence has been halted with improved groundwater management­."

http://en.wikipedia.org/wiki/Groundwater

There are many hydrologist who have suggested you CAN raise the ground back to original or even higher. Look it up.

[Sinick]

I agree with this assessment. Humanity must realize that we can't fool Mother Earth with foibles like New Orleans, Las Vegas and Los Angeles. If it weren't for technology, we simply would not be unable to populate these climes. If you think about it, it is foolish to build metropolises in the midst of the desert, in an area with no access to water or in one of the most intense floodplains on the planet.

Too much water--not enough water--too much brio. How much longer will we tempt fate?

[backhandpath]

Sinick, where else would you suggest locating a seaport?

[noneIn2008]

In the 1950's the Corp already noted the next viable port.

[doctorj2u]

The US government has NEVER committed to doing what must be done to protect New Orleans. Now explain to me again why I pay taxes to this government?

[backhandpath]

Again it seems it seems the Corps here is setting us up for the let-down. {Protect the city no, reduce the risk yes.}
What does that Mean? Isn't that a contradiction? Simple Question:
How to simultaneously Reduce Risk by Not Protecting the City?
We just know that with each News Cycle lately, the Corps seems to be begging-off future responsibility for maintaining their current work. Well, we beg to know then: What the Hell is the Corps of Engineers Good For If They Can't Do Their Job?
This man who is Now Shirking His Duty is basically telling any future investment to give up on New Orleans.
He is telling the Citizens of New Orleans to Give Up on their Future.
Aren't we getting tired of Commanders who come out in public to Contradict the Commander in Chief?
What this Fey Coward Commander is saying here is NOT what the President said in his brief Tinkle-stop Tour of New Orleans.
This General is surrendering in the face of his mission and his country and frankly I am ashamed. Most of what the Corps does leaves me angry, but this leaves me ashamed and somewhat worried.
The "Commander" of the outfit that flooded New Orleans is telling everyone to Run.

Thanks, Mr, Brown. You are the only person reporting this change of strategy.

[Bienville]

Where is the Can-Do American spirit?

The nation that defeated the USSR and the Nazis and tamed a continent can't build a reliable levee system. We're just helpless little babies.

[noneIn2008]

Mother Nature will win. Give it up.

[maxfax]

Tell it to Florida.

[TryToBeFlexible]

You pay taxes to this government because that is the law, and you will be prosecuted if you don't. Got it?

[6bd]

Time to consult the Dutch.

[Bienville]

Did you know the Dutch came to New Orleans in the 1950s to learn how we do it? They took the concept of the Wood pump, invented in New Orleans, to use in The Netherlands. We stood still and the Dutch got to work.