Copthall Tunnel on HS2 route

completed

The Copthall Tunnel is an 880-metre long green tunnel near West Ruislip in west London, part of the HS2 high-speed railway between London and the West Midlands. It was constructed using approximately 1.2 million cubic metres of material excavated from the nearby Northolt Tunnel, redesigned as a cut-and-cover tunnel to reuse material on site and reduce lorry journeys. The main tunnel structure is complete with earth covering placed above, and landscaping including planting of trees and vegetation will continue over the next two years. The tunnel is designed to withstand aerodynamic forces from trains traveling up to 200 mph and includes five ventilation shafts. The project also involved diversion and reconstruction of Harvil Road with a new bridge over the railway.