The contractor will electrify 74km of the Shotts line railway from Holytown Junction to Midcalder Junction between Edinburgh and Glasgow.

The work will involve installation of the electrification infrastructure including vegetation clearance, site and geological investigation, design, piling and mast installation, wire runs, safe supply of power, integration into the wider electrified rail network, energisation and all aspects of compliance with industry standards and regulation.

In addition, 17 structures on the line will be removed or replaced, with an increase in the heights of parapets (side walls) at a further 10 bridges. New station footbridges will be built at Addiewell and West Calder, while platform extensions will be carried out at three intermediate stations (Carfin, Shotts and West Calder). Livingston South station will also be redeveloped.

Following completion of the work in 2019, electric services will be introduced on Edinburgh-Glasgow Central via Shotts.

Martin C Smith, managing director Carillon Powerlines, said “We are delighted to have been awarded this contract to electrify the Shotts line across central Scotland and we look forward to working with the project team to enhance the railway network.”

Transport minister Humza Yousaf said: “This contract award is a major step forward in the delivery of the electrification programme and rail passengers across North Lanarkshire and West Lothian will feel the benefits for many years to come with an improved service on the line.”

Iain McFarlane, head of programme management for Network Rail, added: “This contract is a significant milestone for the delivery of the Shotts electrification project and further underlines our commitment to investing in and enhancing our infrastructure as part of our UK-wide railway upgrade plan.”