Date registered: Sep 2004
Vehicle: 95 E300
Location: Inside my head
Mentioned: 0 Post(s)
Quoted: 392 Post(s)
RE: New Orleans
George Bush built the levees.
Ever since the original planning for construction on the current ring levee system was initiated the USACE said that the system would be built for a Category 3 hurricane. That is what they did. It sustained itself over the course of a lot of storm surges.
What they did not do was build the levee in anticipation of land subsiding and sea level rising. It was not part of the thinking back then because that was a time before subsidence and sea level rise were known to be at work. The levees were static, the system is not.
Worse, a particular attribute of storm surge has only recently been recognized--that it rapidly attenuates in marsh. Louisiana has lost thousands of square miles of marsh in the past decade. It has lost hundreds of square miles since the current ring levee was constructed. Engineers used historical flood and storm surge patterns to construct the ring levee. Since then the marsh has died exposing the levee system to more direct impact of storm surge.
It was only in the past 3 years that definitive subsidence rates have been reliably computed. Google Roy Dokka for info on that. It is a great piece of geodesy for people who are interested. From these data and analysis it is quite clear that the problems of south Louisiana are incredibly difficult and that there are no quick, cheap, and easy fixes for the Big Easy.
The initial belief that the concrete panels were improperly installed was based on seismic return data. Those data indicted that the panels were not planted into the deep, resistant soil but were instead buoyant on the surficial muck. That would have been a huge liability lawsuit on the firms that won the contract for construction.
Subsequent to the seismic analysis the USACE actually pulled many of the intact panels that were supposed (by seismic data) to be improperly installed. It turned out IN EVERY CASE that the seismic data were wrong. This catastrophe research is being conducted by several independent research engineering groups.
It maybe possible to buy-off and/or trick all of the engineers and scientists working on this, but I doubt it. I think the final results will indicate that the levee system behaved as designed and failure was predictable under present circumstances. After that the conspiracy theorists will have a go at it and then we'll find that George Bush really was on the Grassy Knoll.
The taxpayers have to decide whether they are willing to fund perpetual protection in a subsiding and degrading environment.
This is NOT the type of system faced in Holland. It will give a false sense of engineering competency to apply the Low Country experiences in the Mississippi Distributary System. The Mississippi System is far more complex and dynamic.