The 82-year-old Bankhead Tunnel was supposed to be closed until Wednesday morning to allow the Alabama Department of Transportation to replace an emergency electric generator.

The closure will last for another day.

According to James Gordon, spokesman at ALDOT, the two-lane tunnel underneath the Mobile River will be closed until Thursday while crews install the new generator.

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Gordon said it was the first time in the tunnel’s history that the emergency generator has been replaced. The tunnel first opened in 1941.

“Everything is brand new,” he said. “The wiring, over the years, was maintained. But now, it’s a matter of everything being new.”

He said that work crews alerted ALDOT’s Southwest Region that “they ran into a snag,” Gordon said, and that the work will have to last for another day. The tunnel is expected to reopen early Thursday.

Motorists can use the Causeway, Africatown Boulevard, Interstate 165, Water Street and Government Boulevard as alternatives during the closure, and follow traffic control signage.