[StBernard] Engineers Say Lessons from Katrina Studies Can Benefit Communities Nationwide

[Westley Annis]

PERCEPTION: The Mississippi River-Gulf Outlet (MRGO) is a "Hurricane
Highway."

REALITY: The myth that MRGO, a rarely used shipping channel, is a 
hurricane
highway was widely reported after Hurricane Katrina, and continues 
today. It
goes something like this:  during a hurricane, storm surge from the 
Gulf of
Mexico is amplified within the long section of the MRGO and funneled
straight toward New Orleans.

Not so, according to complex computer models that re-created storm
conditions. The reality is that for large storms, the
 channel of the 
MRGO
simply cannot carry enough water to cause flooding. On the contrary, 
the
modeling indicated that following Katrina, the MRGO enhanced the 
post-storm
drainage of surge waters from flooded New Orleans back out to the Gulf.

The computer modeling did indicate that for smaller hurricanes, the 
geometry
of MRGO and nearby canals might have the effect of increasing the storm
surge by a small amount (less than half a foot).

While there may be valid reasons for and benefits to closing the 
channel,
the false perception that MRGO is a hurricane highway should not 
influence...

So this organization agrees with the Corps of Engineers
that the MRGO was not a factor in the flooding?

Exactly what was the C.O.E.'s reasoning for now 
closing the MRGO?


that decision.

JLY