"No one expected that weak spot to be on a canal that, if 
    anything, had received more attention and shoring up than 
    many other spots in the region. It did not have broad 
    berms, but it did have strong concrete walls.

    Shea Penland, director of the Pontchartrain Institute for 
    Environmental Studies at the University of New Orleans, 
    said that was particularly surprising because the break 
    was "along a section that was just upgraded."

    "It did not have an earthen levee," Dr. Penland said. "It 
    had a vertical concrete wall several feel thick.""