Low Water Creates Navigation Challenges

Low-water conditions are causing issues on many of the country’s navigable rivers, not just on the Lower Mississippi.

On the Upper Mississippi, the St. Louis gauge had fallen to –0.35 feet by the afternoon of October 8. Forecasts stretching out over the next four weeks called for it to gradually fall to –1.5 feet.

Bernie Heroff, St. Louis district co-chairman for the River Industry Action Committee, said one of the most concerning areas was at Mile 166, known as Cliff Cave, where the depth was 9 feet, 6 inches in one portion of the channel.

“If we continue to have dry weather, and the St. Louis gauge continues to go negative, that will be concerning,” he said.

Although no formal tow size or draft restrictions were in place on the Upper Mississippi, Heroff said most companies are loading to 9 feet, 6 inches in the St. Louis area.

The dredge Potter was stationed at Upper Mississippi Mile 39.5 near Commerce, Mo., but was expected to move by October 12 to Mile 37.5, near Burnham Island, and then to Mile 125.5 at St. Genevieve, Mo., from October 13 to around October 16 before moving to Mile 166.5. The Corps of Engineers planned to mobilize a mechanical dredge soon to begin dredging at the Corps Service Base in St. Louis to ensure that the Potter had enough depth to get back to its dock when dredging is complete. The Corps was also “very actively” surveying problem locations, Heroff said.

On the Illinois Waterway, carriers were discussing whether it might make sense to reduce the recommended draft from 9 feet, 6 inches to 9 feet, said Terry Bass, president of the Illinois Marine Carriers Association. IRCA recommended placing heavier barges in the middle of the tow.

The Corps of Engineers was surveying at Mile 47, just north of Pearl, Ill., with a buoy boat headed there soon, he said. Companies reported some instances of “bump and go” issues at that location. Other problem areas were at Mile 78, just below LaGrange, Ill., where Indian Creek dumps into the river and Mile 117, just below Havana, Ill., where some buoys had been dragged off base and had to be reset.

The Coast Guard is compiling a list of both “bump and go” incidents and any hard groundings, Bass said. Coast Guard notices also reported shoaling at Upper Mississippi Mile 261.4 on October 7.

“We’re hoping we don’t lose any more [depth] than what we have because we’re not going to get any rain,” Bass said.

The Coast Guard reported that the dredge Barry J would be active on the left descending bank of the Illinois River between Mile 142.9 and 143.6 from October 7 until further notice. It also broadcast a safety notice to mariners October 7 reporting shoaling at Illinois River Mile 136.4 on the right descending bank.

Bass led a conference call October 7 to touch base with IRCA members and remind them that if an area of the river was causing problems to please report it. They also heard from a representative of the National Weather Service’s Lincoln, Ill., forecast office, who described the drought and the need for rain.

“Right now, everybody’s pretty much holding their pool, so that’s a good thing,” Bass said. “Hopefully it stays that way, but we don’t have any relief in the next two weeks, anyways.”

Bass said that occasional brief rain showers aren’t helping much at this point. Vegetation is so deprived of water that it absorbs rainwater before it can make its way to the watershed.