The U.S. Army Corps of Engineers, which exploded a Mississippi River levee late on May 2 to relieve pressure on floodwalls at Cairo, Ill., is starting preparations for a similar diversion in Louisiana next week.
The Corps pumped explosive slurry from barges into pipes in the Birds Point-New Madrid Floodway in Missouri, flooding 130,000 acres of farmland to drop river levels. Water streamed through the breached levee at a rate of 550,000 cu ft per second.
The river level at Cairo fell to 60.2 ft by noon on May 3 from 61.72 ft late the previous day.
“We executed the plan, and it performed as expected,” Col. Vernie Reichling, Memphis District Corps commander, said in a statement.
“We are now moving to the next steps, which are opening the two outflow crevasses at the southern end of the floodway,” near New Madrid, Mo., he added.
The breach diverts but rechannels the river so cities downstream are preparing for the possibility of flooding. Tennessee, Louisiana and Mississippi could experience river levels not seen since the historic flood of 1927.
The Corps plans to open the Bonnet Carre spillway, which is designed to ease pressure at New Orleans by raising some or all of the 350 bays along the structure, spokeswoman Rachel Rodi said. That process can take about 36 hours, she said.
The go-ahead would come from Maj. Gen. Michael J. Walsh, who OK'd the breach in Missouri after protesters lost their appeal to the U.S. Supreme Court.
The Morganza floodway, near Morgan City, La., is under consideration for use after Bonnet Carre, but no decisions have been made, Rodi said.
Meanwhile, in Memphis, the Mississippi River was at 43.7 ft on May 3; it is expected to reach 48 ft by May 10, said Steve Shular, spokesman at the Memphis/Shelby County Emergency Management Agency.
The river could maintain that level for a week to 10 days, he said.