State Considers Doubling Size Of River Diversion To Combat Land Loss

Jan 17, 2019

Louisiana’s Coastal Protection and Restoration Authority (CPRA) released a draft of its new annual plan at the monthly CPRA Board meeting on Wednesday, Jan.16. At the meeting, officials said they plan to seek permits for a significantly bigger Mid-Breton river diversion.

 

Diversions are one of the ways the state plans to combat coastal land loss. They are essentially channels dug between the Mississippi River and nearby marshes. The muddy river water flows through the diversion to the marsh, building new land as the sediment piles up.

 

The first two diversions -- the Mid-Barataria and Mid-Breton -- are both south of New Orleans. They’ve been controversial from the start, as many commercial fishers are concerned that diversions will bring in too much fresh water and change the salinity and overall health of the estuary, which in turn could decrease their catch.

The diversions would be operated at specific times of year, when the sediment load in the river is highest. According to the 2017 Coastal Master Plan, the Mid-Breton Diversion was expected to move up to 35,000 cubic feet per second (cfs) of water. Now, officials seeking permits for up to 75,000 cfs -- more than double the original size.

CPRA deputy executive director Bren Haase says after studying the project more closely, officials realized the increased flow could build land faster without making major changes to the overall design.

“It appears we can increase the amount of sediment…without really affecting project location or cost,” Hasse said.

The state hopes the Mid-Breton diversion will be flowing within the next 10 years.

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