The machine, named Verena, after pioneering British mechanical engineer Verena Holmes, has started work on the Grain to Tilbury electricity upgrade project, a critical part of National Grid’s The Great Grid Upgrade, designed to future-proof the UK’s electricity transmission network.
The project will replace the existing 1960s Thames Cable Tunnel between Tilbury and Gravesend, which has reached the end of its useful life.
The VSM 15000, which has a 15m internal diameter, is being used to sink the launching shaft for tunnelling under the River Thames. It will first excavate the 48m-deep shaft in Tilbury, and then be transferred to Gravesend to construct the target shaft.
Ferrovial BEMO JV will use a Herrenknecht mix shield TBM to build the 2.2km-long high-voltage (400kV) cable tunnel.
The VSM is operated remotely from the surface and removes the need for operatives to enter the shaft during construction. Unlike traditional shaft construction methods, the VSM operates in a slurry environment, balancing slurry levels with groundwater to prevent water inflow and ensure safe, efficient progress through challenging geology. Ferrovial says this approach delivers enhanced safety, speed, and environmental performance, and sets a new benchmark for UK shaft construction.
Ferrovial BEMO JV project director Borja Trashorras said launching Europe’s largest diameter VSM at Tilbury was a milestone achievement for the team and for UK infrastructure.
“This technology allows us to deliver the Grain to Tilbury project with enhanced safety, efficiency, and environmental performance. We’re proud to be working in partnership with National Grid and Herrenknecht to bring this pioneering solution to life, helping to future-proof the electricity network for generations to come.”
National Grid project director Mark Farmer said the Grain to Tilbury project was helping to future-proof the UK’s electricity network.
“The launch of the vertical shaft sinking machine marks a major milestone for the project. Through collaboration and innovation, this technology is helping to deliver resilient infrastructure under the Thames, securing reliable electricity for the decades ahead,” he said.
