The following is a news release from the U.S. Army Corps of Engineers
NEW ORLEANS– In partnership with state and local leaders, the Corps has developed an Inundation Map to depict anticipated impacts from operation of the Morganza Floodway. As floodwaters progress through the Morganza Floodway to the Gulf of Mexico, the height of the water could reach between five (5) and upwards of twenty]five (25) feet above ground elevation, causing widespread flooding and inundation.
Public safety is the Corps' number one priority and people within the following parishes are encouraged to contact their public officials for further evacuation information: Pointe Coupee, St Landry, St Martin, Iberia, Iberville, St Mary, and Terrebonne parishes. Public notice of operation and required evacuation will be given through your State and local emergency officials and other governmental authorities, as well as media outlets. Notification will be given in advance with adequate time for evacuation; however, expeditious action must be taken to protect life and property.
The Morganza Floodway is part of the Mississippi River & Tributaries (MR&T) system, operation of which is outlined in the Water Control Manual. In extreme high water events, not operating this structure would cause the entire MR&T system to operate in excess of its design (due to the increased pressure). The Mississippi River is continuing to swell at near historic levels, not seen since 1927. One of the ways the Corps can reduce the amount of flooding and impacts of the high water is through operation of the MR&T system.
Congress authorized the Morganza Floodway as a vital part of the Mississippi River and Tributaries Project, to relieve the Lower Mississippi River of excess floodwater, which would otherwise stress the limits of the system. The Morganza Floodway is only operated when existing conditions, combined with predicted stages and discharges, indicate that mainline levees in Baton Rouge, New Orleans and other downstream communities will be subjected to unacceptable risk from high water. The decision to open Morganza is the responsibility of the Mississippi River Commission President Maj. Gen. Michael Walsh, commander of the Corps' Mississippi Valley Division in Vicksburg, Miss.