NETWORK Rail engineers have successfully completed the first phase of repair works on the Redbridge Viaduct in the Scottish Borders.
The project involved a portable dam being set up beneath the structure to create a safe dry working area for the team, with 600 square metres of scour mattress and 400 tonnes of permanent rock shield being installed on the bridge.
The rail management firm said the works will protect the red sandstone, five-arch listed structure against future erosion through scour protection and masonry repairs. The scour protection involved the removal of the existing riverbed around the base of the bridge pier to allow for the installation of a scour ‘mattress’ filled with concrete, which will act as a shield to prevent damage from fast flowing water.
Prior to setting up the dam, the project team worked with the River Tweed Commission to relocate fish to another part of the river before the water was drained to form the dry working area – this process is to be repeated at each subsequent pier as work progresses.
Christina Thomson, Network Rail’s project manager for the work, said, “The team has delivered the first of three phases of work to Redbridge Viaduct; essential maintenance that protects the piers of the viaduct from scour erosion and in turn, helps maintain the railway infrastructure. We’ve worked collaboratively with Scottish Borders Council throughout and with the River Tweed Commission and our environmental and marine engineering specialists to ensure our activity has minimal impact to the river’s existing habitat – and will continue to do so throughout the rest of the project.
“The viaduct is an historic Victorian structure that continues to play an important role in carrying passenger trains on the Borders Railway route. When work is complete in October, we won’t need to undertake repairs on this scale for many years to come.”