Network Rail is investing £2.3m as part of the Great North Rail Project to build a new railway bridge high enough for 25,000-volt overhead cables to pass underneath.
The bridge rebuild is needed so a £78m electrification scheme along 13 miles of railway can take place.
The major investment will ensure that older diesel trains can be replaced by cleaner and longer electric rolling stock.
By 2025, the electric trains will provide passengers with greener, more comfortable, and more reliable journeys.
To make way for the overhead lines, seventeen structures – like Chew Bridge in Westhoughton – need to be overhauled.
It will be removed on Sunday, January 22, and a new steel bridge will be built in its place on Sunday, February 19.
William Brandon, scheme project manager at Network Rail, said: “This vital work on the bridge is one of the first pieces of the jigsaw needed to deliver the Wigan-Bolton electrification project. It makes room for new cables needed for the introduction of greener, cleaner and more reliable electric trains planned between Wigan North Western and Bolton in the future.
“The project does mean the railway will have to close over the two Sundays. I thank passengers and local people in advance for their patience while we carry out this vital work.”
Plans to build the new bridge in Westhoughton were approved by Bolton Council in May 2021.
The new deck will be made up of steel beams to better withstand heavy farm machinery and road vehicles.
The bridge will also be finished with materials of a similar colour to the existing bridge in keeping with what was there before.
Anyone planning to travel is urged to check www.nationalrail.co.uk in advance to see how their journey is affected.