TUPELO, Mississippi (Reuters) - Barge traffic resumed along an 11-mile stretch of the drought-ravaged Mississippi River near Greenville, Mississippi, but dozens of vessels waited their turn on Thursday to pass in the shrunken waterway.
The Mississippi River, the country's primary highway for barge traffic, has dropped as much as 14 feet in the drought that has also withered crops in the Midwest and triggered wildfires in the West.
The resulting changes in water currents and conditions have made navigation especially tricky and sometimes hazardous. At least 66 Mississippi River vessels have run aground this year between Natchez, Mississippi, and Caruthersville, Missouri, U.S. Coast Guard Lieutenant Ryan Gomez said.
The latest incident occurred around dawn on Wednesday, just hours after the Coast Guard opened the channel near Greenville. Seventeen of the roughly 100 ships stuck since Monday made it through before one became lodged in the sand, forcing authorities to close the channel again for roughly 12 hours.
Traffic resumed late Wednesday afternoon with southbound vessels going through first, then northbound. After all those boats get through, the Coast Guard will continue directing river traffic on a staggered schedule, Gomez said.
As of Thursday morning, some 50 vessels remained backed up in the channel, waiting for their turn to pass.
Barge operators typically haul some $180 billion in goods annually, and the Mississippi River is their main artery with some 566 million tons of freight going up and down the inland waterway each year, according to the American Waterways Operators, a national trade association representing tugboats, tow boats and barges.
The drought's effect on the river has caused logistical and financial woes for the barge industry.
Barges must unload 17 tons of cargo for every one-inch loss of water and 204 tons for every one-foot loss of draft, said Tom Allegretti, president of the trade association.
Draft is the vertical distance between the ship's waterline and the lowest point of its keel.
It would take 360 semi trucks and 80 rail cars to haul the freight unloaded by one tow on the Mississippi River under those conditions, said Ann McCulloch, spokeswoman for the American Waterways Operators.
Barge operators are losing an estimated $10,000 per day for every one of their boats that sits idle near Greenville, McCulloch said.
With 97 vessels idle on Monday and Tuesday, and 105 vessels idle on Wednesday, according to Gomez, that's nearly $3 million in lost revenues in three days.
"It's a day-to-day situation now to manage the stoppage," McCulloch said.
If water levels drop further, prices could rise on the raw commodities commonly shipped by boat, including coal, grain, petroleum and steel.
Taxpayers also share some of the drought's financial burden. The U.S. Army Corps of Engineers has dredged the river almost nonstop since the start of the drought with equipment costing as much as $85,000 per day, Corps spokesman Kavanaugh Breazeale said.
Dredging removes the silt that falls to the bottom of the river - a problem that accelerates as water levels drop. The Corps must keep the channels at least nine feet deep and 300 feet wide for safe passage of vessels.
Conditions were expected to improve in the short-term near Greenville, where the Coast Guard projects the river will rise about one foot by Monday.
But it forecasts a one foot decrease by Monday in Memphis, which has had its own headaches this summer. On August 9, the American Queen steamboat - a multilevel passenger vessel carrying some 300 pleasure passengers - got stuck near Memphis.
The river there could hit 10 feet below baseline by Wednesday, the Coast Guard said. That is nearing the historic low set in 1988 when river traffic came to a halt and an estimated $1 billion in revenue was lost.
(Editing by Colleen Jenkins, Greg McCune and Vicki Allen)
This story was refiled after official correction to reflect revision by American Waterways Operators in the eleventh paragraph with new freight figures