A new 2.2km tunnel beneath the River Thames between Kent and Essex has been completed 49 days ahead of schedule.
The work is part of The Great Grid Upgrade project to install new high-voltage electricity cables, running from Gravesend to Tilbury.
The Caroline Bore Machine (CMB) has completed a 2.2km tunnel 49 days ahead of schedule. Picture: National Grid
The new tunnel will replace the Thames Cable Tunnel, which dates back to the 1960s and is nearing the end of its operational life.
Project director Mark Farmer described the breakthrough by the tunnel-boring machine (TBM), named Caroline, as a “fantastic achievement”.
He said: “Everyone involved has worked together to deliver an exceptional performance safely and efficiently, helping us reach this important milestone sooner than anticipated.”
The project is expected to play an important role in supporting Britain’s future electricity needs as demand for cleaner power continues to grow.
More than 10,000 concrete tunnel segments have been installed to create the tunnel lining, while more than 16,000 tunnel rings were constructed during the drive.
In addition, more than 40,000 cubic metres of chalk has been excavated, with most of the material now set to be reused at the Port of Tilbury.
The project will now move on to its next stage.
Work will include removing the giant tunnel-boring machine, completing construction inside the shafts and headhouses, and preparing for the installation of the new high-voltage cables.
Mr Farmer said the scheme would help strengthen the network “as demand for cleaner electricity continues to grow”.
The Grain to Tilbury project is replacing the existing Thames Cable Tunnel. Picture: National GridThe Grain to Tilbury project hopes to improve the electricity and power network in Kent and Essex. Picture: National Grid
School children were offered the chance to name the tunnel-boring machinery.
Taking inspiration from influential women in engineering, the TBM was named after Dame Caroline Haslett, who was president of the Women’s Engineering Society.