The major challenge of the electrification work between Manchester and Bolton in 2015 will be the Farnworth Tunnels.
The two tunnels date from 1838 and 1880. In preparation for electrification, the smaller tunnel will be reinforced with concrete and signalling will be installed to allow bi-directional working on the single line. This work will take place at weekends commencing mid-February and will necessitate weekend line closures. Once this is complete, a limited service will be able to operate in both directions through the one tunnel. This will allow the larger tunnel to be widened to eventually take two tracks and overhead line equipment.
The main works will commence on 2 May and run until 4 October, 2015.
There will be a limited Monday – Friday train service, from 06:00 – 22:00hrs with 4 paths an hour for trains in each direction through the operational Farnworth tunnel. Northern Rail plans to operate 6 car services where possible to enhance capacity. Beyond these times and on Saturdays and Sundays, replacement bus services will operate.
Northern Rail plans to operate 1 tph Preston – Hazel Grove, 1 tph Blackpool North – Victoria and 1 tph Clitheroe – Victoria. These will be supplemented at peak times by First TransPennine Express services using 3 and 6 car Class 185 units. Southport – Airport services will be diverted via Atherton line and Kirkby – Manchester services will be diverted to terminate at Bolton with an additional stop at Westhoughton.
The work also involves re-sighting one of the Farnworth platforms, lowering a section of track, removing a pedestrian crossing at Kearsley and replacing it with a footbridge and installing new track around Moses Gate. Once completed, an upgraded track speed of 100mph will allow faster journey times between Bolton and Manchester.
Farnworth, Moses Gate, Kearsley and Clifton stations will be closed throughout the works and a rail replacement bus service will be in operation.