NEW ORLEANS — While the water level in the Mississippi River is low saltwater intrusion becomes a problem for parishes that rely on the river for fresh water.
On Monday, the U.S. Army Corps of Engineers, New Orleans District began construction of an underwater sill across the bottom of the Mississippi River channel to slow the progression of salt water from the Gulf of Mexico.
Construction of the saltwater sill began in the river at mile marker 64 near Myrtle Grove, La.
Contractors will build the sill to an elevation of -55 feet. At that height, USACE says they will monitor the progression of the saltwater wedge to determine if additional height is needed to meet the saltwater intrusion mitigation.
“The Mississippi River’s volume of water has fallen to a level that allows salt water from the Gulf of Mexico to intrude upstream. Denser saltwater moves upriver along the bottom of the river beneath the less dense freshwater flowing downstream,” the Army Corps said in a release.
USACE constructed a similar underwater sill in 1988, 1999, 2012, 2022, and 2023 in the river.
The sill will naturally erode when the Mississippi River returns to the flow levels required to push the saltwater wedge back down the river to the Gulf of Mexico.
► Get breaking news from your neighborhood delivered directly to you by downloading the new FREE WWL-TV News app now in the IOS App Store or Google Play.