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For some reason the local paper saw fit to edit this down to a single
7" column and print it inside the A section.
They also retitled it from the original headline of "Experts Say
Faulty Levees Caused Much of Flooding" to "Experts Say Storm Surge
Burst Faulty Lake Levees" which is confusing at best and (IMHO)
misleading at worst.
NEW ORLEANS, Sept. 20 -- Louisiana's top hurricane experts have
rejected the official explanations for the floodwall collapses that
inundated much of New Orleans, concluding that Hurricane Katrina's
storm surges were much smaller than authorities have suggested and
that the city's flood- protection system should have kept most of the
city dry.
The Army Corps of Engineers has said that Katrina was just too massive
for a system that was not intended to protect the city from a storm
greater than a Category 3 hurricane, and that the floodwall failures
near Lake Pontchartrain were caused by extraordinary surges that
overtopped the walls.
But with the help of complex computer models and stark visual
evidence, scientists and engineers at Louisiana State University's
Hurricane Center have concluded that Katrina's surges did not come
close to overtopping those barriers. That would make faulty design,
inadequate construction or some combination of the two the likely
cause of the breaching of the floodwalls along the 17th Street and
London Avenue canals -- and the flooding of most of New Orleans.
...
The center's researchers agree that Katrina's initial surge from the
southeast overwhelmed floodwalls along the New Orleans Industrial
Canal, flooding the city's Lower Ninth Ward as well as St. Bernard
Parish. They believe that a little-used Army Corps navigation canal
known as the Mississippi River Gulf Outlet helped amplify that surge,
although they acknowledge that this surge was larger than the system
was designed to control.
But the researchers have strong evidence that Katrina's subsequent
surge from the north was several feet shy of the height that would
have been necessary to overtop the 17th Street and London Avenue
floodwalls. It was the failures of those floodwalls that emptied the
lake into the rest of the city, filling most of New Orleans like a
soup bowl.
On a tour Tuesday, researchers showed numerous indications that
Katrina's surge was not as tall as the lakefront's protections. They
showed a "debris line" that indicates the top height of Katrina's
waves was at least four feet below the crest of Lake Pontchartrain's
levees. They also pointed out how the breached floodwalls near the
lake showed no signs of overtopping -- no splattering of mud, no drip
lines and no erosion at their bases. They contended that the pattern
of destruction behind the breaches was consistent with a localized
"pressure burst," rather than widespread overtopping.
The center has also completed a computerized "hindcast" of Katrina,
which has confirmed the evidence before their eyes. Their model
indicates that most of the surge around the lake and its nearby canals
was less than 11 feet above sea level, and that none of it should have
been greater than 13 feet. The Army Corps's flood-protection system
for New Orleans was designed to handle surges of more than 14 feet
above sea level.
more.