A fault on a train between Potters Bar and Alexandra Palace means that some lines are blocked. As a result, trains running between these stations may be revised or delayed by up to 15 minutes.
Disruption is expected until 08:00.
Customer Advice:
Great Northern services are unable to call at Hadley Wood in the direction or Moorgate. Your journey will be delayed by at least 15 minutes. Please check journey planners for further information.
If you are travelling from Hadley Wood and need to travel towards Moorgate or London - please travel towards Welwyn Garden City and change at Potters Bar for a return service towards Moorgate or London from here.
If you are travelling towards Hadley Wood or New Barnet from the direction of Welwyn Garden City - please travel towards Oakleigh Park and change here for a service back towards Hadley Wood or New Barnet.
You can use your ticket at no extra cost on alternative Great Northern services via any reasonable route.
Planning your journey:
You can see a live map of the network here. This will show where your journey is likely to be affected.
You can also use an app to find up-to-date information.
Can you tell me more about the incident?
Great Northern had a report of a fault on a train, and this is now causing delays to other services travelling through this area.
Normally, when a fault on a train occurs, Great Northern crews will gather details and report this to their Fleet teams. If possible, the defect will be fixed promptly, and they will get the train on the way. Their initial steps are designed to take around 10 minutes.
However, sometimes the fault cannot be fixed in this time frame. In this case, wherever possible, the train will be taken out of use and sent to a depot. This does take additional time, as the crew will need to make sure that everyone's managed to leave the train.
If this can't be done either, Great Northern will send their specialist engineers to site, known as "fitters". They have fitters based in key locations around the network, 24 hours a day, and they are able to attend anywhere on the routes. Once they are on site, we'll then monitor progress updates and ensure that the railway can be reopened as promptly as possible.
Until the defective train can be moved, we will try to find a way to get other trains around the issue. This depends how many lines are available, and whether the signalling equipment is set up to allow trains to be routed around the problem. This is more often the case on the major routes, but not always. Great Northern will work with Network Rail's controllers to decide how many more trains can be sent through the area, and if this isn't possible, we'll see what alternative solutions are available to help you continue your journey.
Check before you travel:
You can check your journey using the National Rail Enquiries real-time Journey Planner.
Compensation:
You may be entitled to compensation if you experience a delay in completing your journey today. Please keep your train ticket and make a note of your journey, as both will be required to support any claim.