An overhaul of a rail viaduct on the Manchester and Liverpool line that opened in 1830 has started with high-tech mapping.

Network Rail has commissioned survey work from LiDAR specialists Commendium, with support from heritage consultants Wardell Armstrong, as part of a US$4.6 million project to overhaul and preserve the Sankey Viaduct in Newton-le-Willows in north west England.

The LiDAR data was handed to Network Rail’s design team and used to make a detailed 3D model that engineers can use in repair and monitoring work.

Rail pioneer George Stephenson designed the viaduct to take the railway over a 160m valley. As an historic structure, it has been protected Grade I listed status since 1966. Today it carries two tracks used by up to five freight and passenger services an hour.

Network Rail has also worked with council planners from St Helens and Warrington.