Disruption between Balham and Clapham Junction expected until 21:00 

Route(s) affected

between Balham and Clapham Junction

Description

A fault with the signalling system between Balham and Clapham Junction means some lines are blocked. Trains running through these stations may be delayed by up to 20 minutes or revised.

Disruption is expected until 21:00.

Customer advice:

Due to a signalling failure in the Balham area, fewer lines are available for trains to run on. This means you may experience some delays or last minute alterations. Please allow at least an extra 20 minutes to complete your journey.

Please note this is also causing some delays to Thameslink services.

Service Alternations:

Gatwick Express and Southern still expect the following changes to services;

• Gatwick Express services are suspended until 21:30. You can use alternative Southern and Thameslink services between Brighton and London

• Southern services between Watford and East Croydon are suspended. You can use London buses between these stations instead to reach your destination. Alternatively, you can use LNWR services between Watford Junction and London Euston. You can use London Underground services from London Euston for connections to other London Stations

• Southern services between East Grinstead and London Victoria may be diverted or terminate early

• Southern services between Bognor Regis and London Victoria may be diverted or terminate early

• Southern services between Horsham and London Victoria may be diverted or terminate early

  
  

  For the latest information continue to check station screens, listen to station announcements and use online journey planners to reach your destination.

Ticket Acceptance:

You may continue to use your existing ticket at no extra cost on the following services:

• Alternative Southern routes

• Thameslink services between Gatwick Airport and London Bridge / London Victoria

• London Northwestern Railway between Watford Junction and London Euston

• South Western Railway between Portsmouth and London via Wimbledon

• London Overground between Clapham Junction and Shepherds Bush

• London Underground services between London Terminals

• London Trams between East Croydon and Wimbledon

• London Buses between East Croydon and London Victoria / London Victoria to London Bridge

Planning your journey:

You can see live departure boards, a live map of the network and an alternative route guide.

If you're travelling in the London area, you can plan journeys on alternative routes by using the TfL Journey Planner.

The Gatwick Express / Southern apps will also help you plan your journey.

Can you tell me more about the incident?

An axle counter failure is affecting trains travelling in both directions on the route between Balham and Clapham Junction. This is also affecting the points in this area.

This part of the network uses axle counters to detect whether trains are in the area. These are electrical systems which check the passage of train wheels and 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 an axle counter 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.

Axle counter faults can be caused by a number of different issues, including electronic faults and debris coming into contact with them. Network Rail manage the signalling system, including axle counters, and their staff will be investigating as quickly as possible.

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.