State of Louisiana touts coastal restoration projects to take pressure off the Bonnet Carre Spillway

Proposed Ama and Union river diversions could be used as flood protection tools with Army Corps approval

State of Louisiana touts coastal restoration projects to take pressure off the Bonnet Carre Spillway

NEW ORLEANS, La. (WVUE) - The state of Louisiana has asked the U.S. Army Corps of Engineers to consider using two proposed coastal restoration projects to help reduce the Mississippi River levels north of metropolitan New Orleans.

The Edwards administration wants the Corps to jump start work on the Union Diversion Project on the east bank of the Mississippi and the Ama Diversion on the St. Charles Parish west bank.

“We need to get the federal government to look at the way it manages the river,” said Chip Kline, chairman of the Louisiana Coastal Protection and Restoration Authority.

Last year’s back-to-back openings of the Bonnet Carre Spillway sent trillions of gallons of fertilizer-laden fresh water into Lake Pontchartrain and surrounding waters, prompting algae blooms and damage to fisheries.

Local governments in Mississippi have sued the Corps, as have fishing interests in both Mississippi and Louisiana.

While the Ama and Union projects are barely more than concepts now, supporters have argued they would have less effect on fisheries than the spillway since they are farther from the basin than the spillway.

“I would certainly say it’s an intriguing idea,” said Mark Wingate, Deputy District Engineer for Programs and Project Management for the Corps.

Managing the river differently would require congressional approval, Wingate said.

The Corps is working with the Louisiana congressional delegation to secure the authorization and funding to conduct a study, a process that could take about one year.

“It’s a little premature to say right now that a planned diversion by the state will be beneficial to changes in operation,” said Wingate, who vowed to work with Louisiana and Mississippi officials.

The diversions would be only a fraction of the size of the Bonnet Carre, but could provide a drink of fresh water and sediment to surrounding wetlands and marsh while reducing future spillway openings.

“You are diverting that water into an area that needs it,” Kline said. "You would not have nearly the impact that you saw from the Bonnet Carre Spillway, which could potentially take the pressure of having to operate the Bonnet Carre to that capacity and for that amount of time.”

Any study would also focus on the effects on other stakeholders, including the maritime industry.

Cutting more holes in the river levee could also lead to changes in how fast the river flows, causing sand to build up near diversion sites.

“We know that for every action, there could be potentially negative impact for someone,” Wingate said. “So, we just need to look at these things thoroughly before we could commit to moving forward.”

The project, even if authorized and funded by congress, would take years to engineer, design and build.

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