Lines have now reoepend following a fault with the signalling system between Farringdon and London Blackfriars. While service recovers, trains running between these stations may still be delayed by up to 15 minutes.
Disruption is expected until 13:15.
Customer Advice
Thameslink services will be delayed in the Farringdon area. This is affecting services heading south towards Sutton, Three Bridges and Brighton.
You can continue to travel using your intended route, however, it is recommend that you allow at least 10 minutes extra travel to reach your destination.
Late-running trains may be revised. This means they may not stop at all of the usual stations, or they may terminate part of the way along their usual routes.
As a result, you may need to change trains to get to your destination.
Thameslink know this may mean your journey takes longer. However, it does allow them to get trains and crews back to the right places for the rest of the day's timetable.
Departure boards and station announcements will be kept up to date, so please keep an eye on the latest information when you're travelling.
You can use your ticket at no extra cost on alternative Thameslink 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. For alternative route maps, please check here.
You can also use the app to find up-to-date information.
Can you tell me more about the incident?
A track circuit failure is disrupting trains which travel from Farringdon towards London Blackfriars.
This part of the network uses track circuits to detect the position of trains. These are electrical systems which monitor whether a train is on a section of track. They operate as part of the signalling system, which is designed to be "fail safe".
When a track circuit fails, the signalling system will interpret this as a train remaining in place, even though there may not be a train present at all, or the previous service may have long since left the area.
As a result, further trains cannot be automatically allowed onto the relevant section of track. Train drivers will be stopped by red signals on approach. They will then get verbal permission from the signaller so that they can proceed, and will run at a heavily-reduced speed as far as the next signal. This is so that the drivers will stop safely if they see anything ahead of them.
In some areas, the sections between signals can be several miles long, so this can result in delays building up. Even with shorter sections of track affected, there would still be a delay of at least a few minutes to each journey.
Track circuit faults can be caused by a number of different issues, including electronic faults or obstructions on the track. Network Rail manage the signalling system, including track circuits, and their staff will be investigating as quickly as possible. We're closely monitoring progress updates, and we'd like to thank you for your patience.
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.