Atchafalaya Basin from the Mississippi, Red and Black rivers is diverted into the Atchafalaya at the Old River Control Structure. This flow diverts on average 25 percent of the Mississippi River flow down the Atchafalaya. In times of extreme flooding, the US Army Corps of Engineers may open the Morganza Spillway and other spillways to relieve pressure on levees and control structures along the Mississippi. On May 13, 2011, in the face of a rising Mississippi River that threatened to flood New Orleans and other heavily populated parts of Louisiana, the USACE ordered the Morganza Spillway opened for the first time since
Flow control structure dam across a shallow stream, forcing all of the water to one side to allow it to be easily collected in a canal. This can keep a canal full even with very low flows in a stream. Another simple device is a series of concrete piers installed in a spillway to slow down the descending water so that it does not cause damage at the bottom of the spillway. Flow control structure A flow control structure is a device that alters the flow of water in a stream, drainage channel or pipe. As a group these are passive structures since