An October saltwater intrusion could threaten drinking water in New Orleans, so they'll barge in 36 million gallons of fresh water a day

The US Army Corps of Engineers is planning to barge 36 million gallons of fresh water daily into the lower Mississippi River near New Orleans as an expected saltwater intrusion from the Gulf of Mexico in October threatens the area's drinking water supply, officials said Friday.

The move comes as water levels are plummeting for the second consecutive year after this summer's blistering heat and low rainfall triggered extreme drought over parts of the central US.

As water levels drop, the threat of saltwater intrusion grows in Louisiana as ocean water pushes north into drinking water systems, unimpeded by the Mississippi's normally mighty flow rate.

New Orleans officials anticipate the city will see the effects of saltwater intrusion in late October, according to a Friday news release from the mayor's office. "Please note that this timeline is subject to change, and the City will keep the public informed as the timeline is updated," the release stated.

The Mississippi River is forecast to reach "historic lows over the next several weeks," Louisiana Gov. John Bel Edwards said during a Friday news conference.

To help mitigate intrusion, the state and the Army Corps of Engineers are working to add 25 feet of height to a 1,500-foot-wide underwater levee in the Mississippi River, which was constructed in July to slow the saltwater's progression, Army Col. Cullen Jones said.

The corps also plans to barge millions of gallons of water daily to local water treatment facilities, Jones said during the news conference.