Morganza Spillway Morganza Spillway The Morganza Spillway or Morganza Control Structure is a flood-control structure in the U.S. state of Louisiana along the western bank of the Lower Mississippi River at river mile 280, near Morganza in Pointe Coupee Parish. The spillway stands between the Mississippi and the Morganza Floodway, which leads to the Atchafalaya Basin and the Atchafalaya River in south-central Louisiana. Its purpose is to divert water from the Mississippi River during major flood events by flooding the Atchafalaya Basin, including the Atchafalaya River and the Atchafalaya Swamp. The spillway and adjacent levees also help prevent the Mississippi from changing
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]