Scores of barges and boats have been unable to move on the central section of the Mississippi River because a lock has been closed for emergency repairs.

The Army Corps of Engineers hoped to reopen Lock 25, about 45 miles northwest of St. Louis, allowing traffic to pass for the first time since Wednesday, said spokesman Alan Dooley.

By Monday, as many as 195 barges carrying cargo were waiting to clear Lock 25, Dooley said.

The Mississippi carries hundreds of thousands of tons of cargo, hauling everything from farm products headed downriver from the Midwest to oil and chemicals headed upriver.

Officials said the barges weren’t all sitting on the river as though there’s a traffic jam. Some were being held miles away in “fleeting areas,” spots on the river where barges can anchor and be tied off.

Other vessels, including pleasure boats and river excursion vessels, also were unable to move along the river north of St. Louis until the repairs are complete. There was no immediate word on whether any excursion passengers were affected.

“It’s certainly a roadblock. There’s no way around it,” said Ed Henleben, chair of the River Industry Action Committee, a barge industry group that works with agencies including the Corps of Engineers and the Coast Guard.

The Corps of Engineers said it knew of 13 barge tows that were waiting to clear the lock, or a total of up to 195 barges. A barge tow can consist of up to 15 barges, each barge carrying about 1,700 tons of cargo.

The repair work involved a hinge on a gate, which opens or closes at the ends of lock chambers so the water level can be raised or lowered, taking vessels to different levels of the river.

Andy Schimpf, river projects manager with the Corps’ St. Louis district, said the hinge holding one side of a gate on the lock had been failing. The failing parts had been removed and rebuilt and were expected to be installed Monday night.

Schimpf thought the emergency repairs could cost about $400,000.

“That’s really nothing compared with the cost to the towing industry,” he said.

Henleben said it’s estimated that when the river shuts down to traffic, it costs $30,000 to $40,000 a day per barge tow, which can include up to 15 barges — not per individual barge.

“But we have no real way of putting our finger on the real cost to the industry,” he said. Costs include fuel, insurance, crew wages and employee benefits, among other factors.

“It also has had a pretty significant impact with our customers waiting for shipment of coal or chemicals,” he said.

Lock and Dam 25 at Winfield began operation in 1939, and the Corps of Engineers said the lock is well beyond its 50-year design life.