HS2 contractors switch on conveyor to remove spoil from tunnel

As part of its work as HS2’s main works contractor, the joint venture between Balfour Beatty and Vinci (BBV) has begun using conveyor in a bid reduce the number of HGV movements too and from the site.

The machine moves material excavated from the Long Itchington Wood Tunnel to be reused on other HS2 sites.

In total, conveyor will transport the over 750,000t of spoil over the Grand Union Canal, removing around 30,000 lorry journeys from local roads.

The conveyor will operate until early 2023, before it is dismantled and rebuilt at Water Orton as part of a 1,200m long conveyor which will remove hundreds more lorries from the roads every day.

BBV senior plant and equipment manager Ed Morgan said: “As we build Britain’s new railway, we have big ambitions to reduce the impact on local communities wherever possible and to reduce carbon across the project. Our new conveyor does both. We can now move material from our tunnel boring activity and reuse it at other locations along the route. This will reduce construction traffic and ultimately, help us to contribute to HS2’s carbon targets.

“We’ll continue to embrace innovation and adapt our construction methods to leave a lasting positive legacy on the areas we operate in.”

HS2 Ltd senior project manager Alan Payne added: “We’re working closely with our supply chain to reduce carbon right across the project and find construction solutions to minimise disruption around our work sites. It’s initiatives like this that will help us achieve our ambitious target of being net zero carbon as a project from 2035, helping to put HS2 at the centre of Britain’s sustainable transport network.”

Concerns around the number of HGV movements to and from HS2 sites have been a bone of contention. Most recently, HS2 came under fire after it emerged that plans to remove spoil from its Euston site had been changed, resulting in an increase in HGV movements. The change in HS2’s spoil-removal plan at Euston was a consequence of changes to the station’s design, with the terminus now due to be built in a single stage rather than in two stages as previously planned.

Excavation of the twin bore Long Itchington Wood Tunnel will produce around 500,000t of mudstone and soil, which is processed at an on-site slurry treatment plant and separated out before being transported by the conveyer to be used to build embankments along the route of HS2. An additional 250,000t of material will come from excavations for a railway cutting, which will also be transported by the conveyor.

In December 2021, Tunnel Boring Machine ‘Dorothy’ begun 1.6km journey underneath the Warwickshire countryside. The tunnel passes beneath the Long Itchington Wood, which is classified as a Site of Special Scientific Interest (SSSI).

Dorothy is expected to complete her first bore later in the summer, and this will be the first tunnel breakthrough on the HS2 project.

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