The cut and cover tunnel, 1.5 miles in length, has had the last of its concrete segments put into position
5,020 reinforced concrete segments have been lifted into position for the HS2 pre-cast tunnel near Chipping Warden, Northamptonshire.
The tunnel, a ‘cut and cover’ tunnel, is being built inside of a cutting which will have earth put back on top of it afterwards to blend into the landscape.
Cut and cover tunnels are good for the environment
As well as visually blending with the landscape, cut and cover tunnels also reduce noise disturbances for the environment and nearby residents.
This tunnel is one of five of its kind on the HS2 project, and two of them are nearing completion at Burton Green, Warwickshire, and Copthall, London.
The concrete segments for the tunnel were put into place in the Chipping Warden tunnel, which is in an M-shape, with the separate halves allowing for northbound and southbound trains. The precast wall installation is now finished, and the engineers are now focused on installing waterproofing and internal floor slabs, as well as internal works.
The tunnel was built in two parts, which joined with the final segments being lifted into position near the A361. Excavation, preparatory works, construction, and backfilling were also performed simultaneously where possible to maintain efficiency.
More than two million cubic metres of material was excavated for the tunnel, which is being stored on-site and is ready to be put back and compressed to cover the tunnel.
HS2 reset must get it right this time
The National Audit Office (NAO) released a report in June stating that the HS2 programme only has one chance left to complete its reset.
The cost of cancelling HS2 has rapidly approached the same level as it would cost to complete it. Furthermore, value must be salvaged for the project, with roughly £2bn to be saved by overhauling commercial contracts, and another £500m recommended to be saved in disallowable costs.
Sir Geoffrey Clifton-Brown, the chair of the Committee of Public Accounts, said: “Today’s report confirms that HS2 will arrive years later, cost vastly more – up to £102.7bn – and deliver less than originally planned.
“While governance is improving and HS2’s designation as a mega-project has introduced more streamlined decision-making, more work is needed to complete the reset and restore confidence. The government must prove it has finally gripped this programme and begin to rebuild public trust in a project whose reputation has been severely damaged by a litany of failures, so that it can start delivering long-promised benefits.
He concluded: “The works at Euston present an opportunity to regain reputation, not only by integrating HS2 with a central London terminal, but also by driving regeneration and bringing huge benefits to the local area.”
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