Mississippi River Basin

Project Design Flood Map


Diagram courtesy of US Army Corps of Engineers. Source: Wikipedia. (This work is in the public domain in the United States as it is a work of the United States Federal Government under the terms of Title 17, Chapter 1, Section 105 of the US Code.)

SINCE the early 20th century, the Mississippi has been tending to change its course westward to the Atchafalaya River, which runs a parallel – but currently a steeper and shorter – course to the Gulf of Mexico. Such a shift, however, would leave little water in the current main stem of the Mississippi. According to many, this would be the demise of Baton Rouge and virtual ruin of New Orleans.

Thus the US Army Corps of Engineers was charged to design infrastructure to prevent the main channel flow from being captured by the Atchafalaya. In 1964 the Old River Control Structure (which is the “crosspiece” between the parallel lines of the Atchafalaya and Mississippi Rivers in this map) was completed to insure the Mississippi would maintain its current flow to the Gulf of Mexico. Congress set the water flow to be distributed to the Atchafalaya at 30%, the volume that naturally existed in 1950. Thus the US Army Corps of Engineers stopped time and replaced Nature as the manager of deltaic flows.

Some researchers however believe that, despite the control efforts of the US Army Corps of Engineers, the natural process of deltaic alvusion and alteration that has occurred about every 1,000 years is overdue and its likelihood of occurring is increasing yearly, despite manmade intervention. If Nature does take back control of the Mississippi’s route to the Gulf of Mexico, it will certainly inflict great damage to the nation’s economic investment in the ports, cities and industry of New Orleans and Baton Rouge.