Without the Morganza spillway, New Orleans would be entirely doomed and so would everything south of Baton Rouge, including much of Baton Rouge itself. That spot of flooding you see on the east bank of the river and just south of Baton rouge, extending towards New Orleans, would mean the Port of South Louisiana - the largest port by tonnage in the western hemisphere - would be wiped out. Not to mention the Exxon Refinery - the 2nd largest oil refinery in the nation - would at best have to shut down for many months and at worst be wiped out itself - in addition to the dozens upon dozens of petrochemical plants along the port of south Louisiana. Because someone had some foresight over 50 years ago, this won't happen. The Morganza has only been used once - but it was not for its designed purpose. In '73 it was opened to prevent the river changing course. Had it not been opened the river would have likely changed course but the cities of Baton Rouge and New Orleans would have still been safe. Its never been used for its designed purpose - to prevent catastrophic river flooding of 2 million residents and billions of the nations most vital economic assets - until now. If this works, I think we'll call it even with the Army Corps.