Answers from Army Corps of Engineers on unwatering New Orleans

[Queasy]

Link - site is hammered. Good luck getting in.

edit: Working Link

11:28 PM CDT on Tuesday, August 30, 2005

Q.1. How long will it take to get the water out of New Orleans?

A.1. We are unsure. A number of factors play into this. First, Lake Pontchartrain is at roughly 4.5 feet above sea level and falling. The city is at a lower elevation so water will continue to flow into it until it equalizes.

Once the breach on the 7th Street Canal is closed, Pump Station 6 can pump 10,000 cubic feet per second.

Once the breaches are closed and all of the pumps are running, the pumps can lower the water level ½ inch per hour or about a foot per day. We can get the water level to sea level in four and a half days. The ½ inch rate assumes the late is at normal levels. That would create pumping inefficiency, as could trash in drains and canals that feed into the pump stations.

That?s a ?Best Case? scenario. We don?t know the conditions of all of the pumps. Fortunately most of the pump motors and controllers are at an elevation greater than 5 feet and we hope they weren?t submerged. There could be other unforeseen problems.

We assume the pumps have not been submerged since most pumps are at an elevation greater than five feet above sea level. Pumps are operated and maintained by the local sewage and drainage districts.

Q.2. Why did the levees fail?

A.2. What failed were actually floodwalls, not levees. This was caused by overtopping which caused scouring, or an eating away of the earthen support, which then basically undermined the wall.

These walls and levees were designed to withstand a fast moving category 3 hurricane. Katrina was a strong 4 at landfall, and conditions exceeded the design.

Q.3. Why only Category 3 protection?

A.3. That is what we were authorized to do.

Q.4. How many other areas do you need to get water out of?

A.4. There are at least five ringed levees (areas surrounded by levees) that need to be emptied. New Orleans and Jefferson; New Orleans to Venice (Hurricane Protection project - Port Sulfur to Venice, LA); Chalmette Loop (lower 9th ward of Orleans Parish and Urbanized part of St. Bernard Parrish ); and, Plaquemines Parish non-federal levees have also been overtopped.

Q.5. What will be done to unwater these areas?

A.5. The unwatering plan will be used in these areas as well. Crews and equipment will be mobilized to breach the levees at predetermined locations and allow for gravity drainage into Lake Bourgne or other surrounding water bodies.

For more information, contact the New Orleans District Public Affairs Office at the crisis action center (601) 631-5328. Please also visit the New Orleans District website (www.mvn.usace.army.mil)

 

[loup garou]

Thanks for the post, this is good information.

 

[BlueWeasel]

Damn, 10,000 FT^3 = 75,000 Gallons per second!

 

[Legend]

Q.3. Why only Category 3 protection?

A.3. That is what we were authorized to do.

And with that, no one can claim this is an engineering disaster.

 

[ShotgunSteven]

Originally posted by: Legend

Q.3. Why only Category 3 protection?

A.3. That is what we were authorized to do.

And with that, no one can claim this is an engineering disaster.

Nope, probably just politicians telling people what is needed for a job against the recommendations of those that actually know how to do the job.

 

[rh71]

a foot a day isn't bad.

 

[MrChad]

Originally posted by: BlueWeasel
Damn, 10,000 FT^3 = 75,000 Gallons per second!

Those are some serious motherfvcking pumps!

 

[Jzero]

Originally posted by: ShotgunSteven

Originally posted by: Legend

Q.3. Why only Category 3 protection?

A.3. That is what we were authorized to do.

And with that, no one can claim this is an engineering disaster.

Nope, probably just politicians telling people what is needed for a job against the recommendations of those that actually know how to do the job.

You bet! Building them to withstand category 5 would have been a lot more expensive.

Although it's hard to blame the politicians. You perform a risk assessment where you determine that building the levee to withstand category 5 would result in a manifold increase in cost, yet historically category 4 and 5 hurricanes rarely pass directly through the city, so the chances that such a wall would actually be needed are very slim.

 

[iamwiz82]

Originally posted by: BlueWeasel
Damn, 10,000 FT^3 = 75,000 Gallons per second!

64,800,000,000 gallons of water a day per pump and it will take 4.5 days with all the pumps working

 

[sixone]

Originally posted by: Jzero
You bet! Building them to withstand category 5 would have been a lot more expensive.

Although it's hard to blame the politicians. You perform a risk assessment where you determine that building the levee to withstand category 5 would result in a manifold increase in cost, yet historically category 4 and 5 hurricanes rarely pass directly through the city, so the chances that such a wall would actually be needed are very slim.

Not as expensive as the clean up will be.

 

[Jzero]

Originally posted by: sixone

Originally posted by: Jzero
You bet! Building them to withstand category 5 would have been a lot more expensive.

Although it's hard to blame the politicians. You perform a risk assessment where you determine that building the levee to withstand category 5 would result in a manifold increase in cost, yet historically category 4 and 5 hurricanes rarely pass directly through the city, so the chances that such a wall would actually be needed are very slim.

Not as expensive as the clean up will be.

It's impossible to speculate. I have no idea how much the cleanup will be, nor how much it costs to build various types of levees, but I do know quite a bit about risk assessment and why planners might opt for the lesser of a form of protection.

 

[EMPshockwave82]

Originally posted by: Jzero

Originally posted by: ShotgunSteven

Originally posted by: Legend

Q.3. Why only Category 3 protection?

A.3. That is what we were authorized to do.

And with that, no one can claim this is an engineering disaster.

Nope, probably just politicians telling people what is needed for a job against the recommendations of those that actually know how to do the job.

You bet! Building them to withstand category 5 would have been a lot more expensive.

Although it's hard to blame the politicians. You perform a risk assessment where you determine that building the levee to withstand category 5 would result in a manifold increase in cost, yet historically category 4 and 5 hurricanes rarely pass directly through the city, so the chances that such a wall would actually be needed are very slim.

Very slim, yes. However over a long term situation (aka LIFE) it can be expected that ONE of those storms stronger than category 3 was going to hit New Orleans and it was going to hit them hard. This is one of those politicians saving money things that in my opinion shouldnt have happened. You cant put a price on the lives of the people in New Orleans nor the historical significance of the entire town.

 

[BlueWeasel]

Originally posted by: EMPshockwave82

Originally posted by: Jzero

Originally posted by: ShotgunSteven

Originally posted by: Legend

Q.3. Why only Category 3 protection?

A.3. That is what we were authorized to do.

And with that, no one can claim this is an engineering disaster.

Nope, probably just politicians telling people what is needed for a job against the recommendations of those that actually know how to do the job.

You bet! Building them to withstand category 5 would have been a lot more expensive.

Although it's hard to blame the politicians. You perform a risk assessment where you determine that building the levee to withstand category 5 would result in a manifold increase in cost, yet historically category 4 and 5 hurricanes rarely pass directly through the city, so the chances that such a wall would actually be needed are very slim.

Very slim, yes. However over a long term situation (aka LIFE) it can be expected that ONE of those storms stronger than category 3 was going to hit New Orleans and it was going to hit them hard. This is one of those politicians saving money things that in my opinion shouldnt have happened. You cant put a price on the lives of the people in New Orleans nor the historical significance of the entire town.

Well, in hindsight, everything is a little easier to criticize. I'm sure that the construction cost for CAT 4/5 protection was looked at, but it just wasn't economically feasible.

From an engneering/construction standpoint, every project has to be looked at from a COST vs VALUE perspective, regardless of it's size. The levee/floodwall system is no different.

Looking back, I'm sure everyone agrees that the extra protection would have been worth the cost. But, given the data and budget they had at the beginning of the project, the current system was reasonable.

 

[Armitage]

Originally posted by: EMPshockwave82

Originally posted by: Jzero

Originally posted by: ShotgunSteven

Originally posted by: Legend

Q.3. Why only Category 3 protection?

A.3. That is what we were authorized to do.

And with that, no one can claim this is an engineering disaster.

Nope, probably just politicians telling people what is needed for a job against the recommendations of those that actually know how to do the job.

You bet! Building them to withstand category 5 would have been a lot more expensive.

Although it's hard to blame the politicians. You perform a risk assessment where you determine that building the levee to withstand category 5 would result in a manifold increase in cost, yet historically category 4 and 5 hurricanes rarely pass directly through the city, so the chances that such a wall would actually be needed are very slim.

Very slim, yes. However over a long term situation (aka LIFE) it can be expected that ONE of those storms stronger than category 3 was going to hit New Orleans and it was going to hit them hard. This is one of those politicians saving money things that in my opinion shouldnt have happened. You cant put a price on the lives of the people in New Orleans nor the historical significance of the entire town.

Sure we can - we do it all the time actually. We being the government, insurance companies, etc. For enough money lots of things could be alot safer. But there is only so much money to go around. If you spend more money on the New Orleans levees, you have less to spend on other issues. Maybe public health for example. Which saves more lives in the long run?

Tradeoffs are always made between cost & safety. We live in a very safe society when you consider the rest of the world and our own history - but the last few % are always more expensive.

 

[Bumrush99]

The problem with this country is that we value military expenditures over public works projects like this that could have possibly prevented the scope of this tradegy with the same amount of money it takes to build a couple of stealth fighter planes

 

[Kelemvor]

Q.3. Why only Category 3 protection?

A.3. That is what we were authorized to do.

Awesome

 

[shuan24]

Originally posted by: Bumrush99
The problem with this country is that we value military expenditures over public works projects like this that could have possibly prevented the scope of this tradegy with the same amount of money it takes to build a couple of stealth fighter planes

you sir, are an idiot. Those stealth fighter planes prevent tragedy to the whole nation and helps you sleep better at night.

LA is one of the poorest states in the nation, don't be surprised they didn't get the funding they needed for bigger levees. They probably should've taxed more money out of those girls gone wild videos for using their city. 😀

 

[SarcasticDwarf]

Originally posted by: Jzero

Originally posted by: ShotgunSteven

Originally posted by: Legend

Q.3. Why only Category 3 protection?

A.3. That is what we were authorized to do.

And with that, no one can claim this is an engineering disaster.

Nope, probably just politicians telling people what is needed for a job against the recommendations of those that actually know how to do the job.

You bet! Building them to withstand category 5 would have been a lot more expensive.

Although it's hard to blame the politicians. You perform a risk assessment where you determine that building the levee to withstand category 5 would result in a manifold increase in cost, yet historically category 4 and 5 hurricanes rarely pass directly through the city, so the chances that such a wall would actually be needed are very slim.

Not really. It was a pretty safe assumption that New Orleans would be flooded during our lifetimes. Yes, in any given year the chance was small, but over 50 years it was not. I take this directly from my classes on the subject where we studied the city.

 

[Bumrush99]

Originally posted by: shuan24

Originally posted by: Bumrush99
The problem with this country is that we value military expenditures over public works projects like this that could have possibly prevented the scope of this tradegy with the same amount of money it takes to build a couple of stealth fighter planes

you sir, are an idiot. Those stealth fighter planes prevent tragedy to the whole nation and helps you sleep better at night.

LA is one of the poorest states in the nation, don't be surprised they didn't get the funding they needed for bigger levees. They probably should've taxed more money out of those girls gone wild videos for using their city. 😀

No buddy, you are the idiot for assuming I don't support the military or weapons that are created to protect us. However, the percentage of our tax dollars that go towards the military in relation to other things like education and public works projects is ridiculous.

Here you go

 

[TallBill]

Originally posted by: EMPshockwave82

Originally posted by: Jzero

Originally posted by: ShotgunSteven

Originally posted by: Legend

Q.3. Why only Category 3 protection?

A.3. That is what we were authorized to do.

And with that, no one can claim this is an engineering disaster.

Nope, probably just politicians telling people what is needed for a job against the recommendations of those that actually know how to do the job.

You bet! Building them to withstand category 5 would have been a lot more expensive.

Although it's hard to blame the politicians. You perform a risk assessment where you determine that building the levee to withstand category 5 would result in a manifold increase in cost, yet historically category 4 and 5 hurricanes rarely pass directly through the city, so the chances that such a wall would actually be needed are very slim.

Very slim, yes. However over a long term situation (aka LIFE) it can be expected that ONE of those storms stronger than category 3 was going to hit New Orleans and it was going to hit them hard. This is one of those politicians saving money things that in my opinion shouldnt have happened. You cant put a price on the lives of the people in New Orleans nor the historical significance of the entire town.

So lets all live in padded cells so nobody can get hurt.

 

[Zee]

would it be easier to just abandon New Orleans and start fresh somewhere else? to relocate everyone? Is it wise to rebuild a city that is under sea level?

 

[Jzero]

Originally posted by: SarcasticDwarf
Not really. It was a pretty safe assumption that New Orleans would be flooded during our lifetimes. Yes, in any given year the chance was small, but over 50 years it was not. I take this directly from my classes on the subject where we studied the city.

The likelihood over 50 years of the city flooding was high (sitting below sea level next to bodies of water!), but from what cause? What is the likelihood over 50 years that the city would be flooded by a category 4 or 5 hurricane passing directly over it?

 

[shuan24]

Originally posted by: Bumrush99

Originally posted by: shuan24

Originally posted by: Bumrush99
The problem with this country is that we value military expenditures over public works projects like this that could have possibly prevented the scope of this tradegy with the same amount of money it takes to build a couple of stealth fighter planes

you sir, are an idiot. Those stealth fighter planes prevent tragedy to the whole nation and helps you sleep better at night.

LA is one of the poorest states in the nation, don't be surprised they didn't get the funding they needed for bigger levees. They probably should've taxed more money out of those girls gone wild videos for using their city. 😀

No buddy, you are the idiot for assuming I don't support the military or weapons that are created to protect us. However, the percentage of our tax dollars that go towards the military in relation to other things like education and public works projects is ridiculous.

Here you go

My point is, local state governments are in charge of funding for building infrastructure and what-nots, and since LA is poor, they don't have any money to begin with. Their main source for money is federal grants (also the reason why the drinking age there is 21 and not 18). Basically, the federal govt is in charge of the military, and the states are in charge of their own local roads. You should be blaming the LA's Senator(s) for not getting enough funding for them.

 

[ViRGE]

Originally posted by: Jzero

Originally posted by: SarcasticDwarf
Not really. It was a pretty safe assumption that New Orleans would be flooded during our lifetimes. Yes, in any given year the chance was small, but over 50 years it was not. I take this directly from my classes on the subject where we studied the city.

The likelihood over 50 years of the city flooding was high (sitting below sea level next to bodies of water!), but from what cause? What is the likelihood over 50 years that the city would be flooded by a category 4 or 5 hurricane passing directly over it?

1 in 6.

 

[SarcasticDwarf]

Originally posted by: Bumrush99

Originally posted by: shuan24

Originally posted by: Bumrush99
The problem with this country is that we value military expenditures over public works projects like this that could have possibly prevented the scope of this tradegy with the same amount of money it takes to build a couple of stealth fighter planes

you sir, are an idiot. Those stealth fighter planes prevent tragedy to the whole nation and helps you sleep better at night.

LA is one of the poorest states in the nation, don't be surprised they didn't get the funding they needed for bigger levees. They probably should've taxed more money out of those girls gone wild videos for using their city. 😀

No buddy, you are the idiot for assuming I don't support the military or weapons that are created to protect us. However, the percentage of our tax dollars that go towards the military in relation to other things like education and public works projects is ridiculous.

Here you go

I like how the link you gave doesn't show at least one of the other high percentage items just so it can make military spending look bigger.