The Alex Fraser Bridge is open to traffic again after emergency repairs snarled the Monday morning commute.

Officials closed the bridge's centre lane on the south end to repair a piece of steel jutting out that could damage tires.

The Ministry of Transportation and Infrastructure said a maintenance contractor spotted the loose piece after hearing a banging noise while driving on the bridge Monday morning.

Crews worked quickly to reweld a broken modular expansion joint.

The northbound lane closure backed up traffic on the busy route for several hours. The ministry said it isn't aware of any accidents involving the piece of steel.

Officials warned of congestion after reopening the bridge.

UPDATE - <a href="https://twitter.com/hashtag/BCHwy91?src=hash&ref_src=twsrc%5Etfw">#BCHwy91</a> <a href="https://twitter.com/hashtag/AlexFraserBridge?src=hash&ref_src=twsrc%5Etfw">#AlexFraserBridge</a> emergency bridge maintenance is complete. All lanes open. Expect delays due to congestion. <a href="https://twitter.com/hashtag/DeltaBC?src=hash&ref_src=twsrc%5Etfw">#DeltaBC</a> —@DriveBC

"We apologize for the inconvenience this emergency repair work caused this morning and appreciate the patience of travellers," the ministry said in a statement.

The same joint was flagged for repair in June and welded as a temporary fix. The ministry said the bridge is structurally secure and safe for travel.

Engineers are working on a permanent solution and future repairs will be scheduled outside of peak hours, the ministry said.

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