Rebuilding the Levees

The levees are their own worst enemy because the allow an un natural head of water to build up so when a breach happens there is a much greater surge of water to was away anything in its path rather like a dam bursting. Controlled flooding onto dedicated flood plains would have prevented the disaster from happening also it should be made illegal to build onto any flood plain. Nature has away of reminding people that they do no belong in some locations. I watched a documentary about the flood control on the Mississippi and how every time a threat of flooding made the engineers build the defences higher, and I thought one day that it will fail and that the disasted caused would be a realy big one; then along came Katrina and I was as is normal proved to be right again. Sorry nobody listens to good advice, they all think they know better until it all goes so horribly wrong. Mans hubris!

If you look at what levees were designed to do they actually perform their job well! The problem is that they are built to control the normal flooding that occurs along the greater rivers and are unable to take a 100 year hit that is massive. If you will research flooding prior to levee construction you will find they have saved a lot of lives and property. The breach in New Orleans was bound to happen due to the history of people building in the lowest areas of a major port city-that is as stated building directly in the path of a flood plane -kind of like playing russian roulette and wondering why you lost!!

What I was saying is if you restrict a river in this way, just adding more hight to the levees and thinking well we are safe for now it will come back to bight you because of the hydrostatic pressure builds up and any weakness will be exploited. Then the release of water is that much greater. Just saying it will never happen is foolhardy. Rivers have flooded since they first existed and man should recognise this fact. Then say ok there is a limit to how close to the flood plain we can go. America is a big country and it is not necessary or desirable to build on every square inch. People are surprisingly stupid at times. If you handle enough rattlers one will get to bite you sooner or later. Nature is a wild child and we should be more careful where and how we choose to live.

The only major U.S. city to be built under sea level. I watched a history channel special about New Orleans about 5 years ago and they said if a hurricane ever hit N.O. that it would fill up like a giant soup bowl, and it did. There is a country in the north part of europe that the same thing happened to a long time ago. I think it was around denmark, norway,finland, somewhere in there. That city was also built below sea level and it happened to them (a big surge). I seen their current safety measure and its pretty neat. It's a big swinging gate that closes up when they have a warning so that the surge won't wash in.

The country you are referring to is The Netherlands.

I don't know much about levees and flood prevention, I was wondering why aren't the rivers dredge regularly and the mud collected dump on the river banks to function as a levee. This would prevent rivers e.g. Mississippi river become shallow and overflow. I know this is expensive but the flooding caused by Katrina and Rita is probably more expensive.

You know a thing or two well said.

The foolishness is in trying to rebuild the city there after its vulnerability
was so clearly demonstrated. Even before the hurricane, constant pumping
was required to keep the place dry. The area continues to subside, making
the ongoing problem worse and increasing the hazard. The cost of maintaining
the present unnatural river channel continues to grow, and it adds to the
flooding problems upstream.

The U.S. is not the Netherlands where land is at such a premium that it
must be purchased at the cost of constant pumping and hazard.

If our pol.s were more interested in a viable future in the area than in
shoveling money down the pork barrel they could abandon the worst low lying
area as a bad deal, let the river find its new course, and build a new
economically viable port.

But that would require a modicum of sense and foresight.

"Polititians are not born, they are excreted"

(Apologies for the rant.)

Your views are those of a world weary person who has seen things no man should have to, and yet you show remarkable good sense.

You are talking about Holland. It is also called Netherlands, home of Phillips & Royal Dutch Shell & the world largest port - Rotterdam.

Majority of the country sits on land reclaimed from sea by building dikes. They had no choice except this to gain badly needed extra land.

The difference is they about it in a very systematic & scientific way, unlike US.

You may have seen the swinging gates on Discover channels - Great Structures series.

Yes. While I have the greatest of respect for the U.S.A.C.O.E. as a
'can do` outfit, they are misused by our Government by being asked
"Can this be done?", rather than "Should this be done?", and then being
required to do it on a budget decreased from their origional estimates,
while as we all come to know, in engineering 'everything takes longer
and costs more`.