Morganza Spillway open the Morganza Spillway for the first time since 1973." The second opening of the Morganza Spillway began with the lifting of a single floodgate on May 14, 2011. Diversion of of water from the Mississippi River to the Atchafalaya Basin was planned during this event, with the structure operating at about 21% of its capacity. This diversion was deemed necessary to protect levees and prevent major flooding in Baton Rouge and New Orleans, with the tradeoff of creating possibly severe flooding in the Atchafalaya Basin. By May 18, 2011, a total of 17 gates (the largest number for the
Spillway Spillway A spillway is a structure used to provide the controlled release of flows from a dam or levee into a downstream area, typically the riverbed of the dammed river itself. In the United Kingdom, they may be known as overflow channels. Spillways ensure that the water does not overflow and damage or destroy the dam. Floodgates and fuse plugs may be designed into spillways to regulate water flow and reservoir level. Such a spillway can be used to regulate downstream flows – by releasing water in small amounts before the reservoir is full, operators can prevent sudden large releases