The incident, which occurred next to the Tonbridge-bound track in a ‘remote location’ near Crowhurst, west of Edenbridge, on December 22, was caused by heavy rain.
Network Rail has blamed it on climate change, but Tonbridge Line Commuters [TLC] claims it is a result of failure to invest in what it calls a ‘neglected line’.
The line has been shut in both directions and the infrastructure company said it would need to build a temporary road, tunnel and bridge to address the issue.
It then revealed that the repair works were being hampered because the ground was still moving and was ‘too dangerous to work on’.
It does not expect to reopen the line until March, during which time commuters from Tonbridge are having to use a shuttle train to Edenbridge and then a bus to Redhill.
TLC believes that the alternative arrangements on the Southern line are not frequent enough and reflect the lack of manpower dedicated to rural services.
Network Rail have said the 100-metre length of track, which is now suspended in mid-air, is on an embankment created in the 1830s.
It blamed the problem on ‘every one of the hottest summers since records began’ over the last two decades – and seven of the wettest summers.
John Reynolds, Chair of the Tonbridge Line Commuters [TLC], has said: “We’re not satisfied with the response to this.
“This has been a neglected line for a long time and yet again it seems like the needs of our rural members are being swept under the carpet.
“Southern have shown little interest in this line and seem content to slowly run it into the ground. This incident heaps further misery onto passengers.”
He added: “We accept that nobody can be held to blame for the weather, but we feel that more could be done to provide an alternative service. Yet again it seems like the railway’s convenience trumps passenger service.
“Our principle is that any replacement service should mirror the timetable as far as possible. That means the shuttle train should run half-hourly in the peak and should continue to run at the weekend.
“If the shuttle can’t run to the full timetable, then we call for an express bus that goes directly between Tonbridge and Redhill and vice versa.
“We are making this case to Network Rail and Southern and they have yet to provide a satisfactory answer as to why this cannot be run.
“Passengers on this line have been short-changed enough; let’s not pile on their misery. Network Rail and Southern, you can do better.”
TLC have asked to conduct a site inspection and say they will press for any upgrades to be able to cope with their ‘long-term goal’, a direct service between Tonbridge and Gatwick.