Key milestone for HS2 as half of tunnels completed

HS2, which is at peak construction, supporting more than 31,000 jobs, has now completed excavation of two of its five twin-bore tunnels, with a further two well underway.

The line is being constructed at 350 separate work sites between London and the West Midlands.

In total, high-speed trains will travel through 27.4 miles of twin-bore tunnels – or almost a fifth of the 140-mile route. This means that HS2’s fleet of tunnel boring machines are excavating and building a total of 54.8 miles of tunnel.

New analysis shows that 29 miles – 53 per cent – has been excavated and built so far, eclipsing the length of tunnels bored for the Crossrail line beneath London.

Each TBM operates like an underground factory, excavating the tunnels, lining them with pre-cast concrete tunnel segments, grouting them into place and moving forward at an average speed of between 12 and 16 metres per day.

Once the drives are finished, HS2 moves to the next stage of the tunnelling project when other vital features such as the cross-passages, vent shafts and portals will be completed. This comes before the internal fit-out of railway systems including power, track and signalling which allows high-speed trains to operate.

Rail Minister Huw Merriman said: “Reaching this impressive milestone on a project of HS2’s scale shows just how much momentum is behind construction of the line, which, once complete, will have a transformative impact on rail travel for generations to come.

“It’s a significant achievement for the team helping deliver this railway and I’m delighted the project has now supported record numbers of new jobs, demonstrating the vital role it is playing in creating opportunities up and down the country.”

In the Midlands, ‘Mary Ann’ is 1.3 miles into the 3.5-mile drive of the first bore of the Bromford Tunnel between Water Orton in North Warwickshire and Washwood Heath in Birmingham. ‘Elizabeth’ has just started to build the second bore.

A quarterly analysis shows 31,160 were employed directly or through the supply chain on HS2 in the first three months of 2024, an increase of 2,674 full-time equivalent roles over the previous quarter.

Some 1,533 new apprenticeships have been created and 4,258 formerly unemployed people have now found work on HS2 since 2017.

Jackie Roe, HS2’s civils delivery director, said: “The halfway point for our tunnelling programme is a fantastic milestone, but we’ve still got a lot of work to do on the tunnels, including all cross passages, vent shafts and then fitting them out with the critical rail and power systems that will eventually allow trains to safely operate."