There are tailbacks of over five miles on the A17 as the level crossing barrier is stuck down at Swineshead Station.
Traffic is queuing from before Heckington heading east on the road, with queues from Swineshead village in the opposite direction.
Motorists should look to find alternative routes, especially as the A17 around Sleaford is itself congested due to roadworks on the bypass.
Dave Pickwell posted on Twitter: “Any danger of someone coming and opening the barriers at Swineshead Bridge on the A17 so we can all get to work? Been queuing an hour!”
Network Rail has said that it is working to fix the issue as quickly as possible.