New Orleans Declares Federal Emergency as Water Supply Threatened by Saltwater

This is a severe public health threat because when the salt level is high enough, the body cannot process it. Instead, people develop hypertension. Older adults, individuals on dialysis and those with high blood pressure are most at risk. State officials urge residents not to use machinery requiring water, like washing machines, because the salt can rust out their parts.

In June, state officials placed residents in Plaquemines Parish under a water advisory. So far, efforts to stop the saltwater from coming have been ineffective. As of September 27, the saltwater intrusion was about 28 miles south of New Orleans.

Water is already unusable for about 2,000 residents who live between Empire Bridge and Venice, Louisiana. Officials fear about 20,000 residents in Belle Chasse, Louisiana, will be the next to lose their water supply.

Saltwater from the Gulf of Mexico flows into the Mississippi River when the river's level is low because the river is below sea level from Natchez, Mississippi, to the Gulf of Mexico.

The river's current usually flows at about 300,000 cubic feet per second, which is strong enough to push the saltwater away. In mid-September, the river's rate was 148,000 cubic feet per second, allowing the saltwater to intrude.

What Have Officials Done to Prevent Saltwater From Entering New Orleans' Water Supply?

After winning a contract from the U.S. Army Corps of Engineers, workers with Weeks Marine constructed a sill. They hoped the sill would prevent drinking water contamination because saltwater is denser than freshwater.

Therefore, they thought the saltwater would pool in the sill near Myrtle Grove, Louisiana. They took similar measures in 1988, 1999, 2012 and 2022. Workers must rebuild the sill each time because as the river returns to normal levels, the sill naturally erodes.

Saltwater topped the sill in mid-September, so the Corps of Engineers issued a contract to make it taller near Jesuit Bend, Louisiana, while keeping some of the sill at its original level so that large cargo ships could use the navigation lane.

Officials with the Corps of Engineers believe this measure will only provide another 10 to 15 days of drinking water to the region, including residents of New Orleans.

Furthermore, the Corps of Engineers is working with other officials to secure barges capable of carrying freshwater that the barges will deliver to water treatment plants south of the saltwater wedge. Combining the barge water with water at the treatment plants may provide safe drinking water to residents south of the saltwater intrusion.

Weather Conditions Leading to Saltwater Intrusion

The United States Department of Agriculture has issued a disaster designation for 54 parishes in Louisiana because of extreme drought conditions. Over 4.5 million Louisiana residents are living in areas impacted by the drought.

The state has had the driest August since officials began keeping records in 1895, with most areas seeing less than 33% of their average rainfall. The state has also had the 20th driest first eight months of the year, with most areas being 8 inches below normal during the eight months.

Possible Solutions to Saltwater Invasion in Mississippi River

The Army Corps of Engineers is issuing contracts to haul water from other parts of the river to local water plants, but this can be problematic since the entire river is at near-record lows.

Therefore, barges hauling crops down the river often run into sandbars, resulting in the river being closed to traffic for up to 24 hours each time one has an accident. This may delay water from reaching its destination.

The Sewage and Water Board of New Orleans is looking at options to desalinate the water. The board cannot do this independently, but they are exploring the possibility of hauling water from communities further upstream where the salt has yet to reach.

Residents in the affected area are heading to grocery stores to buy bottled water. Retail outlets are having trouble keeping up with the demand.

Everyone is at the mercy of the weather as large amounts of rainfall are needed, which is unlikely to occur until the spring. Therefore, conditions may worsen throughout the winter.

Saltwater from the Gulf of Mexico is moving into the Mississippi River because of the river's near-record lows. President Biden issued an emergency declaration while local and state officials seek out workable solutions.

Authorities have already placed nearly 2,000 residents south of New Orleans under water advisories, and authorities fear they may have to put New Orleans and the surrounding cities under an advisory by the middle of October as water becomes unsafe for human consumption and use in machines requiring water.