London Road in Carlisle will remain closed for emergency repairs.
The southbound carriageway between Close Street and Grey Street will not be opened in time for rush hour as engineers continue to tackle a burst water main.
The road is closed between Close Street and Grey Street.
The burst water main is far more significant than originally thought and teams will be working through the night but will be unable to reinstate the carriageway.
The northbound carriageway is open as normal.
