Low-Water Conditions Forecast To Continue Into Winter

While the Lower Mississippi River has rebounded somewhat from record lows in mid-October, the river is falling again, and low-water conditions are expected to continue.

The Memphis Engineer District held a press conference November 8 to discuss how it is addressing concerns about low water.

Zach Cook, channel improvement manager, said that since June 13, the Corps has moved 16.4 million cubic yards of dredged material, roughly the amount in 5,000 Olympic-sized swimming pools.

On October 17, the gage at Memphis reached –12.04 feet. Historic lows were set at every gage from Cairo, Ill., to Helena, Ark., around the same time, a 350-mile stretch of river, Cook said.

Several inches of rainfall along the Ohio and Mississippi valleys toward the end of October helped the river to rebound. As of the afternoon of November 8, the Memphis gage had risen to –5.34 feet, according to the National Weather Service. However, the weather service forecast called for the river to fall again to nearly –9 feet in Memphis by November 21.

Col. Brian Sawser, commander of the Memphis district, noted that the low water this season follows the previous record lows set last year.

“We saw low water conditions well into the winter months,” Sawser said. “In fact, we were dredging into the month of January just last season, so we would suspect that we’re going to see similar challenges this season as well.

We don’t see a recovery of the river to get back to normal levels for at least the next few weeks. We continue to work with numerous partners to look at the forecasting models that are out there, but we think that it will continue to challenge us as we move into the winter season.”

Sarah Girdner, acting chief of the Hydraulics and Hydrology Branch for the Memphis Engineer District, said the low-water conditions are a result of an  El Niño pattern, the same as last year, which created above-normal temperatures and less rainfall this summer, and that the El Niño pattern is still continuing. Typically, she said, this results in unpredictable and extreme weather conditions. El Niño patterns can only be forecast out by a few months, so there is no way to know if El Niño will continue past February, she said, although early indications are that it could continue through summer 2024. El  Niño patterns typically occur every four to seven years, she said.

Sawser said the Corps continues to have twice-weekly formal conference calls with partners on how best to address these continued conditions, including navigability issues.

Donny Davidson Jr., deputy district engineer, said all indications are that the low water will continue at least twice as long as it did last year since it began in June instead of in the fall months as it did in 2022.

“Usually we would count on this happening about every decade, not back to back,” he said.

However, he noted that as a result of going through similar conditions just last year, both the Corps and industry were better prepared for this year’s conditions and acted proactively, whether that meant a quicker start to dredging harbors or increasing storage and pre-positioning cargoes where possible.

“We are anticipating challenges as we move into the winter months,” Sawser said. “We don’t see a lessening of the low-water effects. Therefore, by virtue of that, I think we’re looking at challenges to the industry.”

It’s likely the Corps of Engineers will dredge for about six months this year, Davidson said. While the Corps spends $4-5 million on dredging in a typical year, it spent about $8 million last year and is likely to spend in excess of $20 million this year, he said, adding that he expects a record year for those expenditures.

Randy Chamness, co-chairman of the Lower Mississippi River Committee (LOMRC), said that historically some rain in November and December helps river levels rise at least a little, so he is hopeful that the falling river will not set any more low-water records, although it could once again become critically low.

“Industry is preparing that we’re going to be around those -9, -10 at Memphis levels for the foreseeable future,” he said. “The question is when are we going to come out of it?”

While the Coast Guard required a maximum draft of 10 feet, 6 inches for southbound tows on the Lower Mississippi, several in the industry proactively reduced their drafts to 9 feet, 6 inches beginning November 8, he said.

Chamness noted that the seasonal reduction in flow on the Missouri River will begin in late November and should reach St. Louis by the first week in December. Additionally, he said, Kentucky Lake on the Tennessee River and Lake Barkley on the Cumberland River had already been reduced to their winter pools, meaning the only hope for river levels to stabilize is for rain, as there is no upstream storage available in the system.

The dredge Jadwin continued to work at Mile 484 (Stack Island) on the Lower Mississippi, with rolling 24-hour closures, Chamness said. The Wallace McGeorge had been allowed to return to deep draft dredging south of Baton Rouge. The Hurley is not currently dredging.

On the Upper Mississippi, the dredge Potter continued to work in the Thebes, Ill., area, according to the St. Louis Engineer District. The dredge Goetz is working on the Kaskaskia River between the Jerry F. Costello Lock and Dam and the mouth of the river. The Pathfinder mechanical dredge is at the Southeast Missouri Regional Port Authority.

“The channel is in as good a condition as it possibly can be for these stages, so we just have to see what plays out,” Chamness said.