M8 Glasgow: Viaducts Face Demolition or Repair

Two elevated bridges carrying the M8 motorway in Glasgow, Scotland, are critically deteriorating, prompting a review of potential solutions by Transport Scotland. The Woodside Viaducts, completed in 1971 and currently supporting approximately 150,000 vehicles daily, have required extensive temporary propping since 2021, with an expenditure of £152 million. These temporary measures have led to reduced lane capacity and lower speed limits.

Transport Scotland is now evaluating three long-term options for the M8 Woodside Viaducts. The cheapest is to demolish the affected section and reroute traffic to the M74, estimated to cost under £125 million and take one to two years. However, concerns exist about the M74's capacity to handle additional traffic. Repairing the viaducts is projected to cost between £125 million and £200 million over up to three years.

The most expensive option involves replacing the viaducts entirely, with costs ranging from £200 million to £500 million and a completion time of up to four years. Transport Scotland acknowledges that demolishing a section would cause substantial disruption, impacting congestion and travel times across the road network. Public engagement events are being held to gather feedback on these permanent solutions.