Illinois, Upper Miss Face Low-Water Conditions
While hurricanes Helene and Milton inundated parts of the Ohio, Tennessee and Cumberland river basins with rain, low-water conditions caused groundings on the Illinois River and threatened the Upper Mississippi.
Terry Bass, chairman of the Illinois River Carriers Association, said that between October 11 and October 13 there were at least five reported groundings, and possibly more, due to severe shoaling. Members of the navigation industry participated in a call with Sector Upper Mississippi representatives that resulted in voluntarily halting traffic between Illinois River Miles 70 and 81 the evening of October 13 until after a survey the next morning. The queue included at least 15 boats, Bass said.
Electronic Aids to Navigation (ATONS) were placed using charting software until physical buoys could be relocated as mechanical issues with a buoy tender prevented immediate deployment, Bass said.
Bass pointed to continued problem areas both above and below LaGrange Lock and Dam. While no firm draft restrictions were in place along the river, some companies had voluntarily called for reducing their own vessel drafts.
At Mile 78, known as Indian Creek, “There is just not enough current on the river to move the sediment out of the way,” Bass said.
Bass was also keeping an eye out at Illinois Mile 87, known as Grape Island, near Beardstown, Ill., which experienced low water issues a few months ago and has already been dredged once this season. Finally, he said Mile 93 at Sugar Creek is another area to watch.
“It’s Mother Nature,” Bass said. “She’s either going to give you too much rain, or she’s not going to give you any at all.”
Bass said the Corps of Engineers reduced some of the flows at Mel Price Lock and Dam over the past few days, which he said was helping to stabilize water levels for now, although he said it was a balancing act because reducing flows too much could affect water on the Upper Mississippi.
Looking ahead, he also said that low water conditions could be made worse this winter when the river freezes, which reduces available draft even more. The Illinois River will also see shutdowns over the winter, with work on the Lockport Lock, Mile 291, scheduled from January 14 to March 11 for installation of new vertical lift gates and sill and seal modifications and repairs. Construction on a fish barrier to prevent the spread of invasive carp is also expected to require periodic closures during the same period.
Upper Mississippi
On the Upper Mississippi, St. Louis Harbor fell to –2 feet on October 16, above the low water reference point of –3.2 feet. That’s much better than in 2023, when it fell to around –3.4 feet for nearly two weeks in September, said Bernie Heroff, co-chairman of the River Industry Action Committee (RIAC), which activates during times of extreme weather conditions on the Upper Mississippi.
Heroff said there had not been any groundings, although, “The channel is getting a little narrower in places.”
Heroff stressed the importance of dredging problem areas and of diligent placement of electronic and physical buoys.
The dredge Goetz was at work at Upper Miss Mile 173, where a condition survey found that the first 200-foot-wide cut nearly had filled back in with mostly 9 feet of depth, according to a dredge schedule from the St. Louis District that was disseminated to industry. Once it finished that work, plans called for the dredge to move to Mile 166.8 (Cliff Cave). The dredge Potter was working at Mile 38, where a survey found 11-foot-deep water in a 600-foot area. Upon completing its work, the Potter was to move to Mile 125 (St. Genevieve).
The condition survey also noted areas of concern at Mile 182, which was surveyed again October 16 and marked with an electronic ATON; Mile 167, which is marked with an electronic ATON; Mile 145 (Michaels Towhead), where a survey was being requested; Mile 128 (Tower Rock Stone), where survey results were expected soon; and Mile 125, which was marked with both electronic and physical buoys.
