The £7.3M project to repair and refurbish the grade I listed, 199-year-old Union Chain Bridge on the English-Scottish border is expected to get the go ahead today as ministers meet to approve the plans.
The bridge spans the River Tweed near Paxton and built by Captain Samuel Brown. It is the oldest iron suspension bridge still in use by vehicles in the UK and is included in the Historic England Heritage at Risk Register because it is in poor condition.
Northumberland County Council and Scottish Borders Council are each contributing £1M to the work and are jointly pushing for further cash from the Heritage Lottery Fund. It is hoped work on site will start early next year, if the funding application is successful.
A Northumberland County Council report says the structure requires repair and repainting, and must be brought up to modern bridge standards if it is to remain open to vehicles.
The masonry pylons and chain anchorages are fixed elements, between which seven other elements of the bridge move together as a machine when loads including wind, temperature and vehicles are applied.
As part of the work, the seven “mechanical” elements require removal, cleaning, inspection, repair or replacement. Work also includes the removal of the two wire ropes, their hangers and anchorages, replacement of the wrought iron hangers, repairs to the cast-iron hanger caps and replacement of the bottom chord steel angle supports.
Work also involves replacing the deck, support timbers, and deck boards. The carriageway width will also be altered, kerbs and walkway widths will also be modified and the chains, links, and pins will be repaired.
Under the plans the railings will be set back from the chain system and continued across the middle section of the bridge, this differs from their current position where they finish short of the centre allowing an uninterrupted view of the chains.
It said the changes were needed because the way the chains engaged with the railings caused structural stresses within the bridge and also there was a need to ensure the safety of pedestrians crossing the middle section.
The work will safeguard the bridge for a further 120 years, if it goes ahead.
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