Old River Control Structure be opened in an emergency to relieve water levels and water-pressure stress on various levees and other flood-control structures, including the Old River Control Structure. The floodway can reduce stress by diverting additional water from the Mississippi into the Atchafalaya. The Morganza Floodway was never used before the construction of Old River Control Structure, and as of 2016 has been opened only twice for flood control since completion of the Old River Control Structure. Old River Control Structure The Old River Control Structure is a floodgate system in a branch of the Mississippi River in central Louisiana. It regulates the
Morganza Spillway was expected in the Atchafalaya Basin regardless of the choice made regarding the Morganza Spillway, the Corps decided to start the 2011 diversion by opening the spillway a bit less than described in scenario 1a (21%, not 25%) The Governor of Louisiana, Bobby Jindal, had meanwhile sent a letter on May 4, 2011, to Robert Gates, the United States Secretary of Defense, requesting that the National Guard be deployed under Title 32 of the United States Code status to respond to record water levels in Louisiana, where there was "a significant probability that the U.S. Army Corps of Engineers [would]