Saturday, October 22, 2022

The US Army Corps of Engineers is dredging the Mississippi River and racing to keep the sea from contaminating drinking water

mmcfalljohnsen@insider.com (Morgan McFall-Johnsen) -
Business Insider

In this photo taken by a drone, the normally wide Mississippi River has been reduced to a narrow trickle, October 20, 2022, near Portageville, Missouri. 
Jeff Roberson/AP Photo

The Mississippi River is at record low levels, stranding barges and allowing sea water to move in with no end in sight.

The US Army Corps of Engineers is emergency dredging to keep the channel open to supply barges.

USACE is also building an underwater barrier in Louisiana to keep the sea out of drinking water.


The Mississippi River's waters have plunged to new lows, grounding cargo barges on the shallow riverbed and allowing seawater to creep up through Louisiana. That's sent the US Army Corps of Engineers into a frenzy of damage control.

At the mouth of the river, the agency is building an underwater levee to stop the creep of seawater from the Gulf of Mexico, which threatens to incapacitate water-treatment plants in southern Louisiana.


Randy Statler sits on a rock to watch people walk to Tower Rock, an attraction normally surrounded by the Mississippi River and only accessible by boat, October 19, 2022, in Perry County, Missouri. 
Jeff Roberson/AP Photo

Meanwhile, further north, USACE is racing to dig emergency dredges in order to maintain a channel of nine-foot-deep water for barges carrying agricultural goods and fuel up and down the Mississippi. Those goods — like soybeans and oil — partially fuel the economy of the central US.

The price of shipping them has skyrocketed in the last month, The Wall Street Journal reported on Friday. AccuWeather estimates the total economic losses at $20 billion.

"Is there an end in sight? No ma'am," Lisa Parker, a USACE public affairs officer, told Insider. "We're at the mercy of Mother Nature right now."


Barges, stranded by low water, sit at the Port of Rosedale along the Mississippi River on October 20, 2022 in Rosedale, Mississippi. Scott Olson/Getty Images© Scott Olson/Getty Images

The waters are receding due to drought in the upper river valleys of Ohio and Missouri, which feed into the Mississippi. In early October — peak harvest season, when barge traffic is high, according to Parker — at least eight barges ran aground in the shallow waters. The Coast Guard imposed new restrictions on how low ships and barges can sit in the water.

The river has only lost more volume since then. In Memphis, Tennessee, water levels have dropped past the record low set in 1988.

Forecasts from the National Weather Service promise no relief over the next 28 days, predicting that river levels will remain low.

Scientists must conduct rigorous analysis to attribute any single event to the climate crisis. However, decades of research show that rising global temperatures are affecting droughts overall, making them more severe and long-lasting.

'As soon as we're done working, we're moving on to the next hotspot,' Parker said


A US Army Corps of Engineers dredging vessel powers south down the Mississippi River on October 19, 2022, past Commerce, Missouri.
 Jeff Roberson/AP Photo

USACE has seven dredging vessels actively sucking up riverbed material at hotspots where the waters are too shallow, from St. Louis to New Orleans, according to Parker. She said they've been deployed 24/7 and have been in such high demand that she doesn't have an estimate for how many sites they've dredged.

"As soon as we're done working, we're moving on to the next hotspot," she said.

On the Louisiana coast, the river is so low that ocean water from the Gulf of Mexico began pushing upstream. USACE is racing to build a 1,500-foot-wide, 35-foot-tall underwater levee to prevent saltwater from creeping further up the river, where it could contaminate drinking water. Already, there's a drinking water advisory in effect for the coastal region of Plaquemines Parish.


An underwater sill is constructed near the mouth of the Mississippi River to block seawater pushing up river, on October 18, 2022. 
USACE© USACE

Contractors were finishing up the levee on Friday, according to Matt Roe, a public affairs officer for the USACE's New Orleans district.

The work won't be done once the levee is completed, though. Engineers will continue to monitor salinity levels in the river. If seawater begins to override the barrier, they plan to build the levee up taller.

As for the dredging team, the 24/7 work may not end for at least another month. Parker said they expect to be dredging "potentially every day."

"We're confident that we'll be able to maintain that nine-foot channel and keep the Mississippi open," she said.

Drone video of low Mississippi River water levels, tugs in Caruthersville, Missouri.


 

Mississippi River at historically low level due to drought


ABC News Chief Meteorologist Ginger Zee joins ABC News Live to discuss how this drought impacts everything from produce to commerce.

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