UPDATED at 4:30 p.m.
By late Sunday afternoon, all lanes of traffic had been reopened.
At least 100 barges broke loose in the Mississippi River about 10:30 p.m. Saturday in South County.
Four of the barges hit the Jefferson Barracks Bridge, prompting the Missouri Department of Transportation and the Missouri Highway Patrol to reduce bridge traffic to one lane in each direction, said Randy Vaughn, spokesman with the St. Louis County Police Department.
The U. S. Army Corps of Engineers has inspected the structure for damage, he said.
The U. S. Coast Guard has shut down river traffic in recovery efforts.
At about 10:30 p.m. Saturday, officials at the Coast Guard Sector Upper Mississippi River received a call that between 50 and 80 barges had broken free of their moorings, according to Coast Guard authorities.
Officials said the barges were floating freely and represented an immediate danger to facilities and bridges in the area.
The boats that tend the barge fleets responded and began securing the barges.
A total of 114 barges were found to have broken away. Officials said that most of the barges have been secured. Nine barges full of coal sank, one of them in or near the navigation channel at mile marker 166 near Cliff Cave Park.
The Coast Guard estimates that at least 11 barges are not yet accounted for. All of the tank barges with hazardous cargo were accounted for and are safe, the coast guard said.