Interesting links related to history of rivers in area and possible impact of flood events:
The Mississippi Levee System and the Old River Control Structure (ORCS)
http://www.tulane.edu/~bfleury/envirobio/enviroweb/FloodControl.htm
Ecology of the Mississippi River Delta Region
Controlling the Mississippi River
http://www.loyno.edu/lucec/mrdcontrol.html
Floods on the Lower Mississippi: An Historical Economic Overview
http://www.srh.noaa.gov/topics/attach/html/ssd98-9.htm
My son goes to Tulane University in New Orleans. Hopefully he got out as I have not been able to contact him. He has weathered these before but nothing like this one.