A key stretch of the drought-ravaged Mississippi River may fall to a record low by mid-December, halting barge traffic and disrupting billions in commerce on the nation's busiest inland waterway.

President Obama on Tuesday was urged to declare an emergency so the U.S. Army Corps of Engineers can take steps to boost the river's flow and deepen the channel along the 200-mile segment between St. Louis and Cairo, Ill.

Sen. Dick Durbin, D-Ill., plans to meet Thursday with the Pentagon official who oversees the corps to ask that it quickly dynamite exposed rock pinnacles and increase Missouri River reservoir flows to keep the river open, the St. Louis Beacon reported Wednesday.

The corps annually reduces Missouri River releases -- mandated by Congress -- to conserve water for spring and recreation. The last time it dynamited Mississippi rock obstructions was during the drought of 1988-89, a spokesman told The Wall Street Journal. The current drought is forecast to extend into next year.

U.S. Coast Guard Lt. Colin Fogarty told the Belleville News-Democrat that the Mississippi is about 2 feet below normal levels and that it may break the low-water mark -- minus 6.2 feet -- about Dec. 15. That record was set in 1940.

Low water has exposed some old wrecks, Fogarty said, but has not threatened navigation.

The American Waterways Operators and the Waterways Council said the Mississippi is almost too shallow for barges loaded with coal, steel and other products. Shippers are lightening their loads, which they say will affect prices.

In a news release Tuesday calling for federal help, the shippers and waterways groups claimed that $7 billion worth of commodities such as corn, grain, coal, crude oil and chemicals would be jeopardized in December and January if Mississippi River traffic is halted.

"The time for action is now, because once the water levels on the Mississippi drop, this will be an even harder problem to solve," said Tom Allegretti, head of American Waterways Operators.

USA Today