Flood protection projects under way
Published 12:00 am Wednesday, July 28, 2010
By ROBIN SHANNON
L’Observateur
ST. ROSE – With the busier months of hurricane season still on the horizon, representatives from the Army Corps of Engineers, who are working on a series of flood protection projects on the east bank of St. Charles Parish, say the area is in the best shape it has ever been in terms of storm protection.
Brad Drouant, project manager for the east bank work, said the corps has 12 active contracts in St. Charles to raise levees, firm up flood walls and revamp or replace drainage structures. He said the nearly $100 million worth of improvements would provide 100-year flood protection for the east bank of St. Charles.
“The work covers the entire alignment from the Bonnet Carre Spillway to the airport,” Drouant said. “It’s about 10 miles of flood protection improvements.”
Drouant said levee sections closer to the spillway, as well as those near Louis Armstrong International Airport, have already been built to 14.5 feet, up from 10 to 13 feet prior to Hurricane Katrina. He also said the corps is also working to raise and fortify about a mile of floodwalls, including one running under the lower portions of Interstate 310 near Airline Highway.
“In addition to raising the walls, we are also going back in and replacing I-walls with the more stable T-walls,” Drouant said. “The walls are required in areas with a restricted footprint for work, such as under the interstate and along the parish lines.”
Drouant said the wall running under I-310 posed a particular challenge because of the minimal amount of space between the ground and the ramps. He said engineers designed an 11-foot-high floodwall and then attached steel plates to the girders of the ramps to further block waves.
Drouant said the floodwall and levee projects would eventually utilize about 1.3 million cubic yards of clay, all of which is coming from the Bonnet Carre Spillway. A continuous stream of dump trucks has been rolling along Airline Highway between St. Rose and Montz over the past couple months in an effort to get the material from the Spillway to the work sites. Drouant said the truck traffic should be diminishing in the coming weeks as projects in Jefferson Parish begin to wrap up.
The corps is also working on improvements to four drainage structures along the flood protection line. Those include the Walker and Almedia drainage structures in St. Rose, the Trepagnier drainage structure near the spillway and the Cross Bayou drainage structure between Norco and Destrehan.
“We just broke ground on the Cross Bayou structure about two weeks ago,” Drouant said. “The new structure will supplement the Trepagnier station, which is just three miles down the road.”
Drouant said the floodwalls and drainage structures are 100 percent federally funded, but said the levee work is split between federal and state sources. He said the federal government would handle 65 percent of the cost, while state officials pick up the tab for 35 percent.
Drouant said most of the work is expected to be completed by early spring 2011, and added that corps officials expect the job to be complete by the June 1 deadline.