THIBODAUX — The reintroduction of fresh water from the Mississippi River into Bayou Lafourche is now on a fast track, with three large components of the work to be completed by the end of 2016.
In addition to the completion of 8.6 miles of bayou dredging, the Bayou Lafourche Fresh Water District and the state will share the cost for a new railroad bridge in Donaldsonville, which will allow for better water flow downstream.
The third project involves building a barrier in the lower part of the bayou to stem the flow of salt water that is increasingly encroaching on water systems that serve residents and Port Fourchon, said Ben Malbrough, executive director of the Bayou Lafourche Fresh Water District.
The first phase of the project was completed in 2011 when 6 miles of the bayou starting at Donaldsonville were dredged to allow for more water to flow without causing flooding.
There was a lull in activity until 2013, when work started again.
Two dredges are working 24 hours a day to continue where the first project left off. The dredges will remove almost 800,000 cubic yards of material, making the bayou deeper and wider than it has been in decades.
The material is pumped via a pipeline to farmland nearby. Malbrough said they’ve had little problem finding farmers who would like the material pumped to their land.
The $20 million dredging project is expected to be completed next summer. The engineer on the project is T. Baker Smith LLC, and the contractor doing the dredging is Bertucci Contracting Co. LLC.
When the project is completed, about half of the 30 miles from Donaldsonville to Thibodaux will have been dredged. The district is looking for more money to dredge all the way to Thibodaux, Malbrough said.
The bayou, which until 190 4 accepted up to 20 percent of the Mississippi River flow, serves as drinking water for 300,000 residents and is the sole source of water for Port Fourchon.
“It’s a really critical freshwater source, and it’s been neglected for so long that everything we’re trying to do is revitalize this water source,” Malbrough said.
The goal is to increase the fresh water being pumped from the Mississippi River into the bayou from 300 cubic feet per second up to 1,000 cubic feet per second. The increase will help push back salt water from the Gulf of Mexico and help fulfill the district’s mission to provide fresh water to the drinking water production facilities along the bayou.
The project also will involve increased pumping at the Mississippi River and the removal of a weir in Thibodaux.
For years, the question of what to do about the railroad crossing in Donaldsonville has been a stumbling block because it restricts the flow of water downstream.
Malbrough said it took a lot of work to set up a meeting with Union Pacific to demonstrate the need to replace the crossing. The railroad company has agreed and will build a new $5 million bridge next year. Half of the funding will come from the state-controlled Coastal Impact Assistance Program and half by the Fresh Water District. The design for the bridge will be completed early next year and then construction will begin, Malbrough said.
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