Chipping Warden tunnel being built off-site in Derbyshire

Construction has begun on the first of five HS2 tunnels designed to blend into their rural settings.

The Chipping Warden tunnel in Northamptonshire, which will stretch 2.5km when finished, is being built offsite at a facility in Derbyshire to speed up construction.


Source: HS2

Tunnel segments are being pre-cast offsite and installed by EKFB

On Friday the first of its 5,000 giant concrete segments was installed by main works contractor EKFB, which is comprised of Eiffage, Kier, Ferrovial Construction and Bam Nuttall.

When complete, these so-called ‘green tunnels’ will be covered with earth and host trees and shrubs, with the intention of reducing disruption for local communities.

Jeremie Martin, EKFB’s project manager, said the installation of the first set of pre-cast units on Chipping Warden project was a “milestone that the whole team is very proud of”.

“This three-year construction programme will benefit from off-site manufacturing making the green tunnel build more efficient than the traditional on-site building method,” he said.

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“The HS2 green tunnels are a first of its kind in the UK. We have designed them as a twin arch ‘M’ shape which is more efficient than the standard box structure, reducing the amount of concrete required, which is a great example of how innovative engineering design can reduce carbon impact.”

The news comes after the beginning of installation of another major HS2 project built offsite, the Colne Valley Viaduct.

HS2-VL-34322-Greatworth green tunnel portal view 2

Source: HS2

The ‘green tunnel’ is designed to blend in with its countryside setting

At the end of May, Align JV launched a 700-tonne bridge building machine to put in place the 1,000 pre-cast units which will eventually comprise the UK’s longest railway bridge.

HS2 will connect London to Birmingham, the East Midlands and North West England with high-speed services.

But the project has been successively scaled down, with a planned branch to Leeds cancelled last year.

Last week, it was announced that the £3bn Goldborne link – which would have improved connectivity with Scotland – would be removed from the HS2 Phase 2b bill.

The scheme has also been blighted by protests by environmentalists, which have so far cost the project more than £120m.

HS2 Ltd is currently engaged in a High Court battle for an route-wide injunction against protestors, while the Home Office last week announced an amendment to the Public Order Bill to outlaw the digging of make-shift tunnels as a protest tactic.

Protestors who engage in such tactics could face a maximum sentence of three years in prison and an unlimited fine.