Disruption between Watford Junction / Willesden Junction and Clapham Junction expected until 14:45 

Route(s) affected

London Overground between Stratford (London) and Clapham Junction

Southern between Watford Junction and East Croydon

Description

A fault with the signalling system at Wembley Central means that some lines are blocked. As a result:

• London Overground services between Willesden Junction and Clapham Junction may be cancelled in full, diverted to Richmond or be revised to terminate at Willesden Junction

• Southern services may be delayed by up to 10 minutes or revised to terminate at a different station on their route

Disruption is expected until 14:45.

London Overground customer advice:

You can use your ticket at no extra cost on London Buses via any reasonable route.

Southern customer advice:

If you are travelling on this route, you may need to change trains to reach your destination. Services that are running will be delayed.

How the service is being affected:

Some trains that normally run between Watford Junction and East Croydon may terminate and restart at Shepherds Bush. You may need to change for an alternative London Overground service towards your destination there and allow at least 20 minutes more time to travel.

Some trains that usually run between East Croydon and Watford Junction will be cancelled in full. You may need to use London Buses for stations between Shepherds bush and Clapham Junction.

No Southern services can currently call at the following stations:

• Watford Junction

• Harrow & Wealdstone

• Wembley Central

If you are travelling to a station between Watford Junction and Wembley Central you can take an alternative Thameslink train to London St Pancras International. From there you can connect with London Overground services from London Euston. London Euston is a short distance from London St Pancras International.

Tickets are being accepted at no extra cost on:

• Thameslink services between London St Pancras and East Croydon

• London Underground services between London terminals

• London Overground services between Clapham Junction, Watford Junction and London Euston, however please note that these services are also being affected by disruption

• London Buses between Watford Junction and Clapham Junction

Please speak to staff and check journey planners for the latest travel information.

Can you tell me more about the incident?

A fault with a signal is affecting trains on the route between Watford Junction and Shepherds Bush.

Signals tell train drivers when it’s safe to continue into the next section of track. The signalling system will show a green light when the track is clear for a long distance ahead, and drivers will then be shown one or two yellow lights to warn them when they are approaching a red signal. This means that they can anticipate the amount of braking that's required to stop before they reach another train or any form of problem on the line.

If a signal develops a fault, it may be unable to show the normal sequence of coloured lights. The signalling system is designed to keep trains safe when this happens, so the affected signal will show a more restrictive indication. Drivers may need to stop and get permission from the signaller before continuing, or travel at a reduced speed through the affected area.

These additional safety measures mean journeys through the area take longer and can cause trains to queue behind one another. In severe cases, services may need to be cancelled, revised or diverted to prevent delays from building up across the wider network.

Network Rail signalling specialists are investigating the fault and will work to repair the affected equipment. Once the fault has been fixed and the signalling system is working normally, trains will be able to run as usual and the scheduled service can begin to recover.

Check before you travel:

You can check your journey using the National Rail 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.