Salt water intrusion in Mississippi River could impact drinking water in Louisiana

New Orleans Mayor LaToya Cantrell has signed an emergency declaration over an intrusion of salt water into the Mississippi River that officials say could impact the water supply in the region.

"We will continue to work with our partners locally and state-wide as we closely monitor this situation," Cantrell wrote on X, formerly known as Twitter.

Officials said weather forecasts indicate that river volume will fall to historic lows in the next several weeks. As a result, salt water from the Gulf of Mexico is intruding upstream in Louisiana.

"Plaquemines Parish has been affected by this issue since June. Drought conditions have only gotten worse since that time, which means additional communities along the Mississippi River could be impacted," Louisiana Gov. John Bel Edwards said in a statement Friday.

Intruding salt water at the Boothville Water Treatment Plant water intake in Plaquemines Parish is impacting the drinking water supply to residents and businesses from Empire to Venice in southeastern Louisiana, local officials said.

The U.S. Army Corps of Engineers constructed an underwater barrier sill in July to create an artificial basin to help delay the ingress of saltwater. The upriver intrusion of saltwater overtopped the sill's elevation earlier this week.

Edwards said additional work will begin soon to further delay an increase of the saltwater intrusion.

Next week, officials will begin making the existing sill larger to further delay the saltwater intrusion by an estimated 10 to 15 days.

The river's water level is forecast to continue to drop and very minimal rainfall to mitigate the circumstances is expected. Local, state and federal officials are working to determine what can be done to protect water systems and water intake points.

"Unfortunately, without any relief from the dry weather we are starting to see the saltwater intrusion creep further up the river despite efforts to mitigate the problems by the Army Corps of Engineers," Edwards said.

"Most importantly, this is not a time to panic or listen to misinformation," he added. "We have been through this situation before in 1988, and we are monitoring this situation very closely and applying the lessons learned. It is extremely important for the public to stay informed and only rely on credible sources for updates during this event."