Trains are not expected to run between Airdrie and Bathgate until Monday 29 April, as engineers assess damage and make the railway safe after discovering a sinkhole.
Track engineers found the sinkhole on Sunday 21 April, and are now carrying out investigations to establish the need for potentially complex repairs.
The engineers – who work for Network Rail and its contractors – are measuring the size and depth of the sinkhole, and investigating whether an underground spring is the cause.
Once they have the answers, they will make a repair plan, and will be able to give a clearer indication of when the line will reopen.
A sinkhole is depression or a hole in the ground, which may be created by dissolution, erosion or collapse of the surface layer.
Sinkholes have caused disruption to the railway in recent years in Ayrshire and, most recently, in Cumbria.
While the investigation and repair work continues, ScotRail services between Helensburgh Central and Edinburgh Waverley will terminate at Airdrie.
Buses will replace trains between Airdrie and Bathgate, calling at all stations in between, and a shuttle train service will run between Bathgate and Edinburgh Waverley.
The train service between Airdrie and Balloch is not affected.
Up-to-date information about train services is available on the National Rail and ScotRail websites.
“Sinkholes like this are very unusual on the railway, and our specialist geotechnical engineers are working tirelessly to identify the cause, as well as planning the repairs, so we can reopen the railway.
“We understand the inconvenience this incident will cause for passengers, and I'd like to thank those who travel on this route for their patience and understanding while work continues.”
Ross Moran, Interim Route Director for Network Rail Scotland
“We are doing everything we can to keep our customers moving while this issue is resolved, with replacement buses between Airdrie and Bathgate.
“Customers should plan their journey in advance and allow some extra time, as the bus service will take longer.”
Phil Campbell, ScotRail Customer Operations Director
It could well be due to Network Rail failing to keep drainage systems properly maintained. Then, when they get these issues, they conveniently blame “climate change”.
Years ago, railway companies used to employ “Linesmen” whose job it was, each day, to walk their allocated section of line looking for issues so they could be repaired before causing any serious damage. All gone under the current Network Rail structure, so they now are far more reactive – only acting when an issue is serious enough to close a line.
Not long after the sinkhole at Grange on the Barrow line, that caused a derailment of a passenger train. Is this a wider problem?
Yes