Network Rail is advising passengers of changes to trains as investigations take place into a gap between the rail and ballast.

The gap was discovered in December near Darton. This was backfilled by engineers but trains have to be kept to a speed limit of 20mph.

Equipment has also been installed to monitor the area, but more detailed investigations are now needed to find a long-term solution.

The line will be closed from the 15th February until the 2nd March to allow for the work to be completed.

Northern says that the Leeds – Nottingham service will divert via Moorthorpe, whilst its Leeds – Lincoln service will operate between Sheffield and Lincoln only and its Leeds – Sheffield service will be split to run between Leeds and Wakefield and between Barnsley and Sheffield.

We have worked hard to provide short-term measures and keep train services on the move, but we now need to establish the underlying cause of the loss of ballast seen in December.

“Our investigations so far have not identified a clear cause but given Barnsley’s strong coalmining heritage, it is crucial we explore if there have been any changes in the ground beneath the railway line.

Arran Crawford, Network Rail route engineer