The Mississippi River drought was big news as barges ran aground, receding waters revealed new historic artifacts, and river traffic briefly came to a halt in October.
But the drought did not end when the canal reopened.
Barges were only able to transport goods in the historically shallow Mississippi because the U.S. Army Corps of Engineers was constantly vacuuming the river bed.
“It’s been a couple of months of pretty intense management,” Lou Dell’Orco, head of operations and preparedness for the USACE St. Louis.
USACE maintains a nine-foot-deep canal down the Mississippi River, allowing ships and barges to pass freely.
To keep this canal open, Dell’Orco had to bring in additional dredges from other districts.
At some points, the three ships operated 24/7, traveling to bottlenecks in the St. Louis by dropping its suction pipes to the bottom of the river, inhaling the material from the riverbed and transporting it through pipes to designated disposal sites – such as a “giant vacuum cleaner”, as Dell’Orco says.
“Our dredger can fill an Olympic-size swimming pool every hour,” he said.
It’s normal for the USACE to keep one dredge in operation 24/7 throughout the season, but not two or three, Dell’Orco said.
A four-day break in the freezing cold around Christmas gave the crews time to do minor maintenance on the ships. One of the dredges left the district around this time, and the other left St. Louis last week, Dell’Orco said.
More rain and snow have improved river conditions and it looks like the end of the crisis is on the horizon.
“Trade is moving without drought constraints,” Deb Calhoun, senior vice president of the Waterways Council, a group that advocates for modern waterway infrastructure, said in an email. “Then we will watch the tide, which usually happens at this time of year.”
Dell’Orco expects its teams to be able to complete dredging by the end of January.
Drought damage control in numbers: 3 dredgers sucking the riverbed in 24/7
As of July, the district of St. Louis has excavated about 9 million cubic meters of material from the riverbed at about 70 sites, Dell’Orco said. In a normal year, they only dredged 3 to 4 million cubic meters.
That’s over 2,700 Olympic pools removed from the riverbed, compared to just 1,000 Olympic pools in a normal season.
This year, the dredging season has also extended at least 100 days longer than usual, Dell’Orco added.
He estimates that it costs about $6.5 million to run two dredges for a month. Add a third dredge, and he said USACE is looking at $10 million a month.
Climate change could make droughts like this year’s more common
The last time Mississippi fell to such an extreme low and required so much management was in 2012.
No research has directly linked these specific droughts to climate change. But scientists believe rising temperatures will intensify droughts across much of the United States.
In this case, a summer with record-breaking heatwaves burned off some of the river’s water, and then flash drought hit the Ohio and Missouri river valleys, robbing Mississippi of the snow cover that normally 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 drought cycle in the river is accelerating.
For example, instead of every 10 to 15 years, a drought may strike a river every five to 10 years.
Forecast maps show that the Mississippi drought may end soon
According to the U.S. Drought Monitor, much of the Mississippi basin is still classified as drought-affected, including lower regions that help farmers transport grain for export.
However, that may end in the next few weeks. Forecasts from the National Weather Service’s Climate Prediction Center give hope that drought will ease much of the Mississippi basin in February.
Above-average rainfall in the northern Midwest can help replenish the river throughout the month. Then Calhoun and Dell’Orco will look for the flood.
Then, forecasts show that the Mississippi basin may not experience drought for the first time in months.
This would give the Dell’Orco team time to maintain the vessel before the dredging season restarts in July.
“It’s a really shorter maintenance season. You have time from March to mid-June to get it ready for work,” said Dell’Orco.
That shouldn’t be a problem, he added. But still “it’s a 90-year-old ship. Requires a lot of TLC.”
Read the original article in Business Insider