Heavy rains in the Midwest have caused the Mississippi River to swell. To relieve pressure on local levees, the Army Corps of Engineers will begin operating the Bonnet Carre Spillway in Norco on Wednesday.
The levees near New Orleans are only built to handle water moving at 1.25 million cubic feet per second -- quick enough to fill the Superdome in about a minute, the Corps estimates. When the river gets going that fast the Corps opens the spillway, diverting some of that water into Lake Pontchartrain.
Army Corps Emergency Manager Heath Jones says the structure is basically a release valve for the Mississippi River.
“Without the spillway, says Jones, “the levees downstream would have to be much higher.”
The Corps will begin operating the spillway on Wednesday. Officials say they’ll open 38 of the structure’s 350 bays to start, then potentially as many as 200 as the crest of the river moves downriver. Right now, the Corps expects to spillway to be open for about a month -- though that could change as the river demands.
The public is invited to attend Wednesday’s opening, which is currently planned for 10am. It will mark the third time the spillway has been operated in 4 years.
Right now, Corps officials do not think they will have to open the Morganza Spillway. That structure is located north of Baton Rouge and performs a similar release valve function, but has only been operated twice: 1973 and 2011.
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