http://www.wwl.com/Morganza-Spillway-now-open/9837980
About 25,000 people and 11,000 structures could be in harm’s way when the Morganza spillway is unlocked for the first time in 38 years. Sheriffs and National Guardsmen were warning people in a door-to-door sweep through the area, and shelters were ready to accept up to 4,800 evacuees, Gov. Bobby Jindal said.
Some people living in the threatened stretch of countryside - an area known for small farms, fish camps and a drawling French dialect - have already started fleeing for higher ground.
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Remember that there are areas within this flood plain that have levees protecting the towns, etc. So not everything will be flooded as I understand it.
The bottom line to all of this is that no one except for the good Lord really knows where the water is really going to end up going. I wonder how many times God is going to have to remind folks that the Mississippi was there first and let it go where it has a mind to.