LOUISVILLE, Ky. (WDRB) -- Work came screeching to a halt on the Milton-Madison Bridge early Tuesday morning when a steel bearing dislodged.

One construction worker was hurt and commuters are now being told to take alternate routes.

The main area of focus for engineers is on one of the south-end piers. It appears the bridge dropped anywhere from 1.5 to 2 feet. When that bearing dislodged, officials say the portion of bridge right above it dropped.

It was a terrifying wake-up call.

"It sounded like a blast," said Roger Aldridge, who lives along the river. "And then the house shook and the windows were shaking."

Around 2 a.m., Aldridge was one of many people in Milton who said they woke up to a loud "pop."

"When they blasted the bridge and were getting the old one out, it shook it," Aldridge said. "But this was actually worse than when they dropped the bridge."

Transportation officials say construction workers were installing a mechanism that will help slide the new bridge onto the old piers, when a steel bearing between the bridge and pier dislodged.

"We were basically just four days away from the slide taking place, and they were working hard on their preparations, and this occurred," said Ky. Transportation Department spokesperson Andrea Clifford.

The incident sent one worker to the hospital with non-life threatening injuries, shortly followed by the bridge's abrupt closure.

"Normally it takes me about 13-14 minutes to get here from where I live," said commuter Lynn Carter

Carter lives on one side of the bridge, and works on the other. She said she was prepared for the scheduled closure later this week, but now she fears it will be closed for much longer.

"I guess we'll manage," she said. "I mean, you have to work."

And although transportation officials won't say how the incident will affect the future of the overall project, they confirmed that the bridge dropped down.

"There is going to be a little drop in the bridge because you have a section that was there that is now missing," Clifford said.

Officials say the drop, which is at least one foot, is the focus of their inspection as they try and figure out where to go from here.

Officials say there is still no telling when the bridge will reopen to motorists, which means commuters will either have to go 26 miles upstream or to Louisville to cross.

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