• President Joe Biden signed a declaration of federal emergency for a saltwater intrusion threatening New Orleans' water infrastructure.
• A lack of rainfall in the has led to lower levels of fresh water in the Mississippi River, allowing saltwater to rise upstream.
• The threat of saltwater has led to a run on single-use water bottles with residents concerned they may lose access to drinkable water.

President Joe Biden on Wednesday declared a federal emergency for a saltwater intrusion in the Mississippi River, which is threatening New Orleans' water infrastructure.

A lack of rainfall has led to lower levels of fresh water in the Mississippi River, which has allowed the denser saltwater layer beneath to rise upstream over the past two months.

Usually, the strength of the river flow in tandem with an underwater sill work to keep the saltwater at bay. But on Monday, the saltwater overtopped the sill, entering the drinking water of Plaquemines Parish in Louisiana.

That same day, Louisiana Gov. John Bel Edwards sent a request to Biden to declare the situation a federal emergency so that the state could draw on funds from the Federal Emergency Management Agency.

Biden's Wednesday approval comes as officials scramble to keep the saltwater from infiltrating more neighborhoods along the Mississippi Valley, which could leave many residents without potable water.

As it stands, drinking water in New Orleans "is safe," according to the Sewage and Water Board of New Orleans, or SWBNO. The U.S. Army Corps of Engineers projects that two New Orleans water treatment plants will be affected by the end of October: the Algiers Water Treatment Plant on Oct. 22 and the Carrollton Water Treatment Plant on Oct. 28.

In the meantime, New Orleans residents have been left wondering how much longer they'll have access to drinkable water. Some have fled to stores in panic to strip the shelves of single-use water bottles, though government officials have urged consumers to remain calm, assuring them that there will not be a water bottle shortage.

"When you go to the grocery stores, the water aisles are wiped out," said Jesse Keenan, a professor of real estate and urban planning at Tulane University.

Mia Miller, a resident of New Orleans' Bywater neighborhood, admits to having picked up a couple of extra liters of bottled water herself:  "You don't want to be caught unaware or be the person who was like, 'Oh, this isn't going to be a problem.'"

But for Miller, like for many New Orleanians, preparing for disaster is just another day in the life. Miller is more concerned that the city's infrastructure may not be equipped to handle this intrusion.

New Orleans City Councilmember Joseph Giarrusso said that the saltwater surge could lead to a loss of adequate water access for residents, especially those in poorer neighborhoods, hospitals and dialysis centers, hotels, local businesses and more.

"The thing I'm worried about more is if we reach...a worst case scenario, how long is it going to affect people, particularly for poor people and for businesses that are trying to make their way? How do they manage all of these costs, and yet another unexpected expense?" said Giarrusso.

Solutions under consideration

At a New Orleans City Council meeting on Wednesday, councilmembers, officials from the SWBNO and from the Department of Homeland Security discussed possible response strategies.

One method would use barges to import massive amounts of freshwater to dilute the water coming into treatment plants so that it can be used for bathing and other non-potable instances.

The U.S. Army Corps of Engineers has also been working to build the underwater sill higher to delay the saltwater from progressing further upstream.

Another proposal is the construction of a pipeline, which would deliver fresh water from further up the river to affected areas downstream. The SWBNO said in the meeting that the estimated cost of the pipeline is $100 to $250 million, which would draw on FEMA funding, though there is no set timeline for when it might be finished.

"They're saying that they can get this thing built in 30 days, which is when we should feel the impacts of the saltwater intrusion," said Councilmember Lesli Harris. "Making sure that there's a date certain on which the construction begins is something that I would like information on."

Precedented circumstances

The saltwater threat in New Orleans is not unprecedented. A similar intrusion took place in 1988, though it only lasted several days before rainfall restored the Mississippi River to regular conditions. In more recent years, saltwater has drifted higher upstream but not to the extent of the past week.

Some New Orleanians are wondering why the city is always playing defense, despite the warning signs of saltwater intrusion in years past.

"The hard part about managing the city is you don't want to over-prioritize resources for something that isn't an issue yet," said Councilmember Giarrusso. "But there's always deferred maintenance and now we are dealing with climate change. We're seeing more stories about saltwater intrusion in other places. And so, it's time to pivot towards having a contingency plan."

"We're always playing the response game," said Miller of Bywater. "You can't just put a band-aid on every time something happens."

Stephen Murphy, the director of Tulane University's Disaster Management Program, agreed: "We need to really think about how we're going to handle this in the future because we can't just continue this process of responding. We need to get out in front of this next time."

This time around, the situation appears different than 1988. Forecasts of low precipitation in the area do not bode well for restoring the river. According to Murphy from Tulane University, 10 inches of rainfall, which could take months, is needed to return the river back to normal levels of fresh water.

"Mother Nature moves at a different rate. She doesn't play by our playbook often," says Murphy.

The climate change connection

The lack of rainfall in New Orleans correlates with predictions about the changing climate.

"The types of patterns that we're observing in our region and throughout the Mississippi Valley are at least consistent with the predictions that are out there that we will have to face increasing frequency and intensity of climate change-driven events," said Josh Lewis, Schwartz professor of river and coastal studies at Tulane University.

Over the past week, nine-year-old Drew Murphy who lives in New Orleans, has found himself with questions about the future of his water supply. Fortunately, his dad is Stephen Murphy, Tulane's disaster management expert, and can help talk it through,

Murphy recalled a recent conversation with his son: "He's like, 'We need to figure out a way so this doesn't happen again.' I'm like, 'Bingo, pal.'"