Salt water wedge in the Mississippi River threatens drinking water in Louisiana

BATON ROUGE, La. (AP) — Salt water from the Gulf of Mexico is creeping up the drought-stricken Mississippi River and threatening drinking water supplies in some Louisiana communities, including New Orleans, prompting the state’s governor to warn Friday he may request federal help.

Gov. John Bel Edwards said during a news conference that he is just a couple days away from requesting an emergency declaration from the federal government to get more agencies to address the issue and authorize the state “to take emergency protective measures with some level of reimbursement available.”

“Unfortunately, we just haven’t had the relief from dry conditions ... so that (saltwater) intrusion is worsening, in the sense that it’s moving further up the river,” Edwards said.

The southeastern corner of the state, Plaquemines Parish, is already under a drinking water advisory due to high salt levels in the water. Bottled water is being distributed to residents.

Typically, the river’s flow is sufficient to prevent salt water from moving far upstream. But for the second year in a ro w, hot and dry weather has lowered the Mississippi River’s flow, allowing a denser, heavier layer of salt water from the gulf to force its way upstream.

The river is expected to hit historic lows in the next few weeks, Edwards said.

“Most of the state has been experiencing prolonged drought and above-average heat, and has presented a number for challenges including wildfires, drought, heat-related deaths, injuries and so forth and now saltwater intrusion,” Edwards said.

Officials are addressing the issue in multiple ways, including heightening an existing sill — an underwater levee used to block or slow the wedge of salt water — and bringing in 15 million gallons of fresh water for residents in impacted areas.

“We’re being proactive. We’re applying best practices and lessons learned from the past,” Edwards said.

But what is needed most right now is rain. And not just in Louisiana, but further north to strengthen the river’s flow, Edwards said.

The governor urged Louisianans not to panic or rush to buy bottled water. Instead, residents will be notified in advance if salt water will impact their area.

“We just need to make sure that we are aware of the situation and that we don’t do anything that would exacerbate it and do anything that we reasonably can, as soon as we can, to help us get through this period of time,” Edwards said.