Wider floodgate to speed up Bayou Chene project

Plans to construct a roughly 400-foot wide floodgate instead of a 250-foot gate on Bayou Chene should allow officials to start construction at least a year sooner on the project.
The Bayou Chene Flood Control Project is designed to prevent flooding in up to six parishes when the Atchafalaya River runs high.
The St. Mary Levee District has had a difficult time moving the project forward with a 250-foot floodgate, said Levee District Executive Director Tim Matte. A U.S. Corps of Engineers permitting process to change the authorized width of the navigable channel from 400 to 250 feet caused the delay in the Bayou Chene project’s progress, he said.
The project involves installing a permanent floodgate on Bayou Chene in Amelia surrounded by steel pilings along with work on Avoca Island to keep flood waters bypassing the bayou and traveling across the island. The project will protect areas in St. Mary, Terrebonne, Assumption, Lower St. Martin, Lafourche and Iberville parishes from flooding.
Levee district personnel plan to close the permanent floodgate when the Atchafalaya River in Morgan City is forecast to reach 7 feet and continue rising.
Officials wanted to use a 250-foot gate because that smaller opening could lower the project cost, and the levee district got letters of support from local industry to use the narrower floodgate, Matte said.
But getting approval to use that width opening would probably take at least another two years, Matte said. Levee district leaders have already spent three years trying to get permit approval.
“We feel like the … savings that we get from a construction standpoint could be easily overcome by the time delay in actually getting the project approved,” Matte said.
Consequently, the levee district is planning to build about a 400-foot wide floodgate. Matte believes the 400-foot opening will be “an easier path than the one we have been pursuing,” he said
Project leaders expect the two project permits for the 400-foot opening could be approved in the next six months to nine months, Matte said.
If everything goes according to plan, the St. Mary Levee District could bid out the construction contract in summer 2017, Matte said. Construction would then probably take 1½ to two years to complete, Matte said.
Corps of Engineers New Orleans District spokesman Ricky Boyett said that, based on discussions with levee district leaders, “we believe that this gate will reduce the processing time” for one of the Corps permits, Boyett said.
Additional required permits include a Department of Army Permit for projects in a navigable waterway and a Clean Water Act permit for projects that will impact wetlands, Boyett said.
Plans to construct a permanent flood control structure on Bayou Chene began after the 2011 high water event.
The district spent $2 million to $2.5 million in 2011 and 2016 to install a temporary flood protection structure because of high water in the Atchafalaya River, which connects to Bayou Chene.
Officials want to finish the permanent structure as soon as possible so they won’t have to spend money again to temporarily block Bayou Chene, Matte said.
Materials for the temporary Bayou Chene flood protection structure are still available on site for officials to use, if another flood occurs before the permanent project is finished, said.
Officials estimate the project will now cost $78 million instead of the previous $70 million estimate, Matte said.
District personnel are “pretty confident” the project will get about $40 million from the Restore Act as a result of the BP oil spill settlement, Matte said. Project leaders hope to pay for the remaining balance of the project with state oil royalty funds and capital outlay funds.
Any additional funds would come from the surrounding parishes that also benefit from the project.
Louisiana Coastal Protection and Restoration Authority spokesman Chuck Perrodin said the Bayou Chene project “is being heavily evaluated” in the CPRA’s 2017 master plan of projects. That master plan is currently under development.