“Everyone is light-loading,” said American Waterways Operators vice president Lynn Muench.

With every inch equalling 17 tons of coal, and barges reducing loads by 2-3ft, Muench said the barge companies were absorbing the loss in profits. “But when it comes to the spot markets, the customers bear the brunt, and the contract losses eventually increase contract prices.”

Alter Barge Line president Larry Daily said river levels were the lowest he’d seen in some time. “1988 was the worst I’ve ever seen, but we’re not there yet. Another three or four weeks, and we’ll certainly be there.”

Alter’s 320-barge and six-towboat fleet has been so pressed by the low levels the company estimates it is losing $US200,000-300,000 per month.

Another barge company, Ingram Barge, said it had limited use of its larger barges because of the narrowed river widths. “Also, there are several spots on the Mississippi where it is one-way traffic or daylight-only traffic,” said P B “Kaj” Shah of Ingram. “Low water levels have caused us to reduce drafts.”

He added that the direst areas of the Midwest waterways was the lower areas of the Mississippi River and Ohio River. “If we don’t get additional rain soon, it is possible we will experience a complete shutdown of the lower Ohio and/or the lower Mississippi at some point during the next few weeks.”

While there is passage of commercial barges on these major water transport lines, the Army Corps of Engineers said any additional water level decrease could significantly impair traffic. According to an industry report, the Corps is to sustain channels for routing channels that are at least 300ft wide and 9ft deep.

An advisory issued by the US Coast Guard earlier this month advised heavier-loaded barges to reposition themselves as soon as possible, specifically in the upper Mississippi. Meanwhile, the Army Corps of Engineers has been working to keep the river open to traffic by using a dredger to deepen the harbour of St Louis.

“Once you’ve lost a day on the river, you can’t recover it,” said Daily. “We’re getting rain, but not enough to cure the river. We need a couple weeks of steady rain every few days.”