A marine construction crew works on clearing rock pinnacles in the Mississippi River at Thebes, Ill. The U.S. Army Corps of Engineers has issued contracts for removing the obstacles near Thebes and at Grand Tower. The work is expected to continue well into 2013.
A marine construction crew works on clearing rock pinnacles in the Mississippi River at Thebes, Ill. The U.S. Army Corps of Engineers has issued contracts for removing the obstacles near Thebes and at Grand Tower. The work is expected to continue well into 2013.
THEBES, Ill. — Work began here recently on removal of rock pinnacles from the Mississippi River that threaten to hamper barge traffic due to low water levels.

Crews contracted by the U.S. Army Corps of Engineers were busy clearing the formations rising up from the riverbed here and at Grand Tower, Ill. Meanwhile, barge traffic has been backed up for miles, as the channel is closed from 6 a.m. to midnight each day.

“There are two spots here at Thebes,” Coast Guard Commander Rob McClelland told AgriNews while he observed the operation from the river bank. “The river level at this gauge is 10 to 11 feet above the pinnacles.”

The lower Mississippi is experiencing low levels following the severe drought that gripped much of the nation’s midsection this year. As a result, the Corps held back water from reservoirs in North Dakota, an act that has lowered the level south of St. Louis — below the locks and dams — even more.

Engineers have indicated that release of water from two Illinois lakes — Lake Shelbyville and Carlyle Lake — are planned and will help raise the river level slightly. But shippers have expressed concern about navigation if the river levels fall too much.

Earlier in December, St. Louis barge company executive Marty Hettel said low river levels could result in higher costs for materials transported on the Mississippi, including agricultural inputs such as fertilizer.

The Corps is mandated by Congress to maintain a navigable channel on the Mississippi with a minimum 300-foot width and 9-feet depth.

The spot here where the work was being done appeared to be quite narrow, likely not much more than the minimum width. Work previously had been carried out in 1998 to remove portions of the pinnacles.

While the Corps is responsible for maintaining the channel, the Coast Guard has other duties.

“The Coast Guard’s role is channel and vessel management in the area,” McClelland said. “We make sure no one’s in the area (while the river section is closed). Our role is to ensure that commerce can proceed safely.”

The Corps has issued 60-day contracts to companies for removal of the pinnacles. McClelland said there are three methods for clearing the areas.

The first is use of a machine similar to a backhoe, to scrape away top portions of the pinnacles. The second option is pounding of the structures with a jackhammer-type device. The final option — if necessary — is drilling and blasting of the underwater formations using explosives.

The lowered river levels on the Lower Mississippi have held up traffic for weeks. Ashley Soper, a dispatcher at Economy Boat Store at Wicliffe, Ky., said she has seen long lines forming.

“They’re waiting for fleet space at Cairo, where they switch out barges,” she said. “In Cairo last week, there were 1,100 barges. I’ve never seen that many. They were waiting for days. They were in a hurry to get down, because they thought it was going to be closed completely.”

Soper added that in some places barges were lined up 10 miles down the river from the landing where she works, which is near the confluence of the Ohio and Mississippi rivers.