The pedestrian underground crossing in Lincoln city centre has been closed due to flooding this weekend and will remain so for some time.
Barriers are at both entrances of the passage as there is standing water.
The pump that clears water from the underground crossing is defective, the county council confirmed.
It is unclear at this stage when the work will start and how long it will take for the issue to be resolved.
A Lincolnshire County Council spokesperson said: “Having received a report of standing water in the subway, we sent a team to investigate. It appears that the pump that removes water from the subway has stopped working. We are now in the process of arranging the necessary works.”