For the third year in a row, Louisiana is constructing an underwater levee in the Mississippi River to slow an influx of salt water from the Gulf of Mexico.

Construction has begun on a saltwater sill near Myrtle Grove to help mitigate the effects of saltwater intrusion up the Mississippi River.

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

Crews have starting work to create barrier to try and slow down salt water from the Gulf that has been surging up river in Southeast Louisiana."The U.S. Army Corps of Engineers, New Orleans District began construction of an underwater sill across the bed of the Mississippi River channel to arrest further upriver progression of salt water from the Gulf of Mexico,

Salt water is moving upriver from the Gulf of Mexico. Drought in the central United States has weakened the mighty river’s flow to the point that it can no longer push out saltier water from the Gulf. For Plaquemines Parish, which draws directly from the river, this intrusion is a threat to its water source.