Disruption between Alexandra Palace and Welwyn Garden City expected until 10:00

A fault with the signalling system between Alexandra Palace and Welwyn Garden City is causing disruption to journeys running through these stations.

As a result, trains may be delayed by up to 15 minutes or revised.

This is expected until 10:00.

Customer advice:

Great Northern / Thameslink

Services travelling from Alexandra Palace towards Welwyn Garden City are disrupted.

To see if your route has been affected, please view the live journey planner here.

Please leave 15 minutes extra to complete your journey if you are travelling this morning, due to the disruption some services may be cancelled or revised at short notice. You may need to use more than one train to complete your journey.

Can you tell me more about the incident?

Staff have been advised of a potential fault to the signalling system at New Barnet. Technicians are on now on site. In order to investigate safely they will need to take blockages of the lines. This means your train may be held or there may be a delay whilst the train you are on is routed onto another line to continue it's journey.

You will be updated once more information is known.

In this particular situation the fault has been confirmed as a 'Track Circuit Failure'. This means the signalling system is unable to automatically verify if the next section of track past the affected signal is clear.

The rail network is designed so that if a signal stops working, trains will stop before they reach it. Whilst this issue is ongoing, train crew will stop at the affected signal and contact the signalling centre to confirm their location. At this point the signaller will verbally authorise the driver to continue towards the next signal. This process adds time to every train’s journey, which means services can experience short delays.

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.