I have seen the report. I also toured the catastrophe zones in March 2006. My understanding from the tour and presentation is that the Lower 9th Ward and Lakeview were inundated because the canal floodwalls failed. While there indeed were some levee failures in the network, the catastrophic flooding was due to floodwalls breaking.
There were so many problems occurring simultaneously that it’s virtually impossible to sort out what by your definition might be classified as ‘catastrophic flooding’ as opposed to some local ‘garden variety flooding’. The levee along the Mississippi River – Gulf Outlet was completely wiped out. The I-wall along the Industrial Canal, the South Breach and the East Bank were overtopped and obliterated… did that occur strictly due to the ‘overtopping’ per se? Or did it happen because of the poor design of the I-wall which even if overtopped didn’t necessarily have to collapse i.e. if you’ve read the reports you know that the water gap caused by the poor design of I-wall quickly caused a sliding soil condition and entire sections were simply shifted along to the point of destruction. And then as I mentioned earlier, there were walls that went down which were not overtopped at all. None of this really matters of course….it all comes down to proper engineering design, selecting the right materials, making sure that everything was constructed properly and then inspected/maintained properly afterwards. Overall, it was an engineering failure pure and simple… many will blame corrupt politicians and deals that allowed substandard materials and methods to be used. None of this exonerates the engineers who put their licenses on the line and can always withdraw their services if asked to do something that compromises proper design.