A fault with the signalling system between Clapham Junction and London Victoria means that trains have to run at reduced speed on the line towards London Victoria.
As a result, trains running between these stations may be delayed by up to 10 minutes.
This is expected until 22:00.
Customer advice:
Some Southern services will be delayed when travelling from Clapham Junction towards London Victoria.
This will mainly affect "Metro" services which call at Battersea Park, as the signalling fault is on the line used by stopping services through this station.
You can still use your normal route, but your journey could take around 10 minutes longer than usual.
Please leave some extra time, especially if you need to make onward connections beyond London Victoria tonight.
Planning your journey:
Live departure boards can be found here.
You can view a live map of the network here.
Can you tell me more about the incident?
Trains may be delayed due to a fault with a signal in this area. In this case, the signal is unable to show the normal coloured light indications to drivers, which means that your train will need to travel at reduced speed on this part of the network.
Railway signals are designed to warn drivers that they have to stop because the system can't yet confirm that the route ahead is clear. In most places, the signalling system will show a green light, or aspect, 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.
Signalling runs on "fail safe" principles, so if the signals can't step through the usual colours, they will instead show a more restrictive colour - for example, red instead of green. This means drivers will be expecting to come to a stop, but in fact, the route ahead may still be clear. This leads to delays whilst trains proceed more slowly than usual.
The signalling system is maintained by Network Rail, and Southern are working closely with them to diagnose the fault and make sure it is fixed as quickly as possible. Until this is done, the train service will be closely monitored to try and keep to the timetable.
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.