Morganza Spillway its present course through the major port cities of Baton Rouge and New Orleans to a new course down the Atchafalaya River to the Gulf of Mexico. The Morganza Spillway, operated by the U.S. Army Corps of Engineers, was opened during the 1973 and 2011 Mississippi River floods. The Great Mississippi Flood of 1927 was the most destructive river flood in the history of the United States, in large part due to the Mississippi River swelling to wide in spots. To prevent a repeat of the Great Flood of 1927, and better control river flooding in general, Congress passed the
Morganza to the Gulf benefits to the marshes and wetlands in the Terrebonne Basin. Safe Harbor: Fishermen will no longer have to leave the area in a storm event. A Reconnaissance Study for the Morganza, Louisiana to the Gulf of Mexico Hurricane Protection Project was authorized by Congress in 1992. Following completion of this report, the United States Congress authorized a Feasibility Study in the Energy and Water Development Appropriations Act of 1995 (Public Law 103-316). The Feasibility Study was completed in March 2002 and the Chief of Engineers letter was forwarded to the Secretary of the Army in August 2002 and supplemented in