THE West Coast main line will close for 16 days in March as Network Rail engineers deliver a 'vital' programme of work to upgrade Carstairs Junction.

The closure of the line, between March 4 and March 19, is the first phase of a three-month programme of work which will also see trains diverted and journey-times extended between March and June for all services between Glasgow/Edinburgh and Carlisle.

The work is part of a £164million Scottish Government investment to modernise the key junction for passenger and freight services.

Engineers will simplify and upgrade the track-layout to clear an existing bottleneck on the network, making it more reliable and able to better cope with passenger and freight demands.

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Work on the route will be 'complex' and Network Rail will complete it in three phases 'designed to manage the effect on services in the least disruptive way'.

During the first phase of the project – between Saturday March 4 and Sunday March 19, there will be no direct services to Glasgow Central and Edinburgh on the West Coast main line through Carstairs.

During the later phases of the project, there will be no direct services between Glasgow Central or Edinburgh and Carlisle on the West Coast main line each weekend.

The closure of the junction will affect cross-border operators including, Avanti West Coast and TransPennine Express.

Liam Sumpter, route director, Network Rail Scotland, said: “Carstairs Junction is coming to the end of its life cycle and with the volume of freight and passenger trains passing through each week it’s important that we modernise this part of the network.

“By completing this crucial upgrade work we will improve the capabilities and reliability of this strategically important junction, providing better future journeys for passengers and more capacity for freight.

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“There’s never a good time to close such an important line but this is a huge and extremely complex piece of work that will safeguard the future of the route for years to come."

Carstairs junction sits 26 miles to the south-east of Glasgow on the West Coast main line.

Currently the junction requires regular maintenance work, as much of the infrastructure through the area is reaching the end of its operational lifespan.

The layout of the junction is no longer suited to today’s pattern and volumes of service with 200+ services passing through the junction on an average midweek day.

Passengers are advised to check with their train operator for the alternative travel plans for their route.