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The US Army has been dredging the Mississippi River 24/7 for 6 months. The drought crisis that grounded barges and unearthed fossils may finally be over. #Army #dredging #Mississippi #River #months #drought #crisis #grounded #barges #unearthed #fossils #finally #englishheadline


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ship deck built with heavy equipment with water shooting into the air over the deck

The US Army Corps of Engineers flushes the water jets of a dredge’s suction head.USACE

The Mississippi River drought was big news when barges got stranded, receding waters revealed new historic artifacts, and river traffic briefly ground to a standstill in October.

But the drought didn’t end when the channel reopened.

Barges have only been able to transport goods down the historically shallow Mississippi because the US Army Corps of Engineers has been constantly vacuuming the bottom of the river.

“There was a few months of pretty intense management,” Lou Dell’Orco, chief of operations and readiness at the USACE St. Louis district, told Insider.

USACE maintains a nine-foot-deep channel down the Mississippi River, so that ships and barges can travel freely.

barge passes under bridge on mississippi river low waters

A barge tows cargo down the Mississippi River, in Vicksburg, Mississippi during a historic drought.Rogelio V. Solis/AP Photo

To keep that channel open, Dell’Orco had to bring in extra dredges from other districts.

At some points, three vessels were operating 24/7, traveling to chokepoints in the St. Louis area, dropping their suction tubes to the bottom of the river, inhaling material from the riverbed, and transporting it through tubes to designated disposal sites — like “a giant vacuum cleaner,” in Dell’Orco’s words.

“Our dredge can fill up an Olympic-sized pool about every hour,” he said.

It’s normal for USACE to keep one dredge at work 24/7 throughout the season, but not two or three, Dell’Orco said.

Dredge ship with four levels and giant steel tripod on the deck for suction pipes

The Dredge Potter, owned and operated by the St. Louis District US Army Corps of Engineers.USACE

A four-day break during a cold snap around Christmas gave crews time to do minor maintenance on the vessels. One of the dredges left the district around that time, and the second one left St. Louis last week, Dell’Orco said.

More rain and snow have improved conditions on the river, and it looks like the end of the crisis is on the horizon.

“Commerce is moving with no restrictions relative to drought,” Deb Calhoun, senior vice president at the Waterways Council, a group that advocates for modern waterway infrastructure, told Insider in an email. “We will be watching for high water next, which is something that normally happens around this time of year.”

Dell’Orco expects his teams can stop dredging by the end of January.

Drought damage control by the numbers: 3 dredges sucking up the river bottom 24/7

dredge long boat with water shooting out of the ends in mississippi river

The Dredge Potter submerges its suction head and shoots water jets to stir up the sand and gravel on the bottom of the river, which is then vacuumed up and moved through 800 feet of pipe to be discharged somewhere outside the channel.USACE

Since July, the St. Louis district has dredged about 9 million cubic yards of material from the bottom of the river in about 70 locations, Dell’Orco said. In a normal year, they would only dredge 3 million to 4 million cubic yards.

That’s more than 2,700 Olympic swimming pools of material removed from the river bottom, compared to just 1,000 Olympic swimming pools in a normal season.

This year the dredging season has also stretched at least 100 days longer than normal, Dell’Orco added.

He estimates that it costs about $6.5 million to operate two dredges for a month. Throw in a third dredge, and he said USACE is looking at $10 million per month.

Climate change could make droughts like this year’s more common

dredging vessel travels down mississippi river aerial view

A US Army Corps of Engineers dredging vessel powers south down the Mississippi River at the height of the drought.Jeff Roberson/AP Photo

The last time the Mississippi dropped to such extreme lows and required this much management was in 2012.

No research has directly linked these particular drought events to climate change. But scientists are confident that rising temperatures will amplify droughts across much of the US.

In this case, a summer of record heat waves baked away some of the river’s water, and then a flash drought struck the Ohio and Missouri river valleys, robbing the Mississippi of the snowpack that usually feeds it.

It’s unclear how climate change will affect the Mississippi River in the long term, AccuWeather meteorologist Paul Pastelok previously told Insider. But it’s possible that the river’s drought cycle accelerates.

Instead of every 10 to 15 years, for example, drought could strike the river every five to 10 years.

Forecast maps show the Mississippi’s drought may end soon

Much of the Mississippi River basin is still classified in a drought, including the lower regions that help farmers transport grain for export, according to the US Drought Monitor.

That could end in the next few weeks, though. Forecasts from the National Weather Service’s Climate Prediction Center offer hope that drought will alleviate across much of the Mississippi River basin in February.

united states map shows february 2023 drought forecast with drought removal likely in the mississippi river basin

The National Weather Service predicts the likely removal of drought in much of the Mississippi River basin in February.NWS Climate Prediction Center

Above-average precipitation across the northern Midwest could help replenish the river throughout the month. That’s when Calhoun and Dell’Orco will be on the lookout for flooding.

map of united states precipitation forecast shows above average precipitation across the north

A rough forecast of precipitation across the US for the month of February 2023.National Weather Service Climate Prediction Center

After that, forecasts show there could be no drought conditions across the Mississippi River basin for the first time in months.

us seasonal drought outlook for january to april shows probability of no drought in mississippi basin

The National Weather Service’s outlook forecasts a likelihood of no drought in most of the Mississippi River basin into spring.NWS Climate Prediction Center

That would give Dell’Orco’s team time to do maintenance on their vessel before the dredging season begins again in July.

“It’s really a shorter maintenance season. You’ve got March through the middle of June to to get it ready to go,” Dell’Orco said.

That shouldn’t be a problem, he added. But still, “it’s a 90-year-old vessel. It needs a lot of TLC.”

Read the original article on Business Insider

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