ST. LOUIS (AP) -- Crews have completed the most critical phase of removing bedrock that threatened barges along a crucial stretch of the drought-starved Mississippi River, staving off the shipping industry's fears that the treacherous channel could close to traffic, the U.S. Army Corps of Engineers said Saturday.
Using excavators and explosives, corps-hired contractors cleared 365 cubic yards of limestone and added two vital feet of depth to the channel near Thebes, Ill., about 130 miles south of St. Louis, the corps said. That phase, which began last month, addressed the most pressing threat to mariners and additional rock removal is expected nearby, the corps said.
"The river rock removal contractors executed their work quickly and efficiently in the primary areas of concern," said Maj. Gen. John Peabody, commander of the corps' Mississippi Valley division. "The work has deepened the channel enough to successfully maintain navigation though this critical reach of the river."
While averting a potentially crippling shutdown of the river, the work wasn't without its inconvenience to shippers. Barge traffic at that stretch has been limited to an eight-hour window each day, causing bottlenecks and slowing transit times of cargo as crews removed the jagged bedrock that threatened to tear barge bottoms to ribbons.
Still, the corps said Saturday, 630 vessels and 6,123 barges managed to make their way through during the rock extraction work.
Barge operators in recent days credited the corps' hustle in addressing the bedrock months ahead of schedule, keeping open the stretch on the river that's an artery used to move everything from corn to grain to construction materials and petroleum. The corps also has strategically released water from lakes into the Mississippi to raise the river in recent weeks, trying to blunt the effects of the worst U.S. drought in decades that has made the river narrower and shallower.
"The Army Corps of Engineers has done a great job of pulling rabbits out of their hat," Rick Calhoun, president of Cargo Carriers, Cargill Inc.'s shipping arm with 1,300 barges, told The Associated Press as crews were closing in on finishing the first phase of the rock clearing. "We believed it was an oncoming crisis, and by hook and by crook it hasn't gotten as bad as we thought. That's great news."
The barge industry is still pressing for U.S. government help from the Missouri River, which feeds into the Mississippi at St. Louis. The agency cut the flow of the Missouri into the Mississippi in November and has rebuffed the industry's pleas that the flow from a South Dakota dam be restored, saying the pullback was needed to protect interests on the upper Missouri.
Barge operators hope that if the corps can keep the Mississippi passable for the next month or so, spring rains, snow melt and the back-to-normal release from the Missouri could raise the Mississippi, erasing any lingering worries about shipping.
Shipping groups have warned that if the waterway there were to drop to a point in which barge weight restrictions were further tightened, shipping would effectively stop. Drafts, or the portion of each barge that is submerged, already are limited to 9 feet in the middle Mississippi, down from 12 feet. Trade group officials say that if drafts are restricted to 8 feet or lower, many operators will stop shipping.
While lessening cargo weight helps barges ride higher, shipping costs increase because more barges are required to move the cargo and tow boats go through more fuel because more trips become necessary.