Giant tunnel boring machine Mary Ann smashed through at Washwood Heath today, marking the end of a 652-day drive beneath the M6, River Tame, and critical National Grid infrastructure – all completed without disruption.

The 125m-long TBM was launched in July 2023 by Balfour Beatty Vinci.

Its crew of 450 specialist tunnellers worked around the clock to steer the 1,600-tonne machine through complex ground conditions at depths of up to 40m.

At peak, Mary Ann advanced 30m per day, installing nearly 3,000 concrete rings made up of segments cast at BBV’s Avonmouth factory.

BBV tunnelling director Jules Arlaud said: “It’s been a challenging drive beneath critical live infrastructure. I’m incredibly proud of our entire team, whose dedication made this possible.”

Around one million tonnes of spoil has been reused on HS2’s Delta Junction viaduct complex, helping cut lorry movements via dedicated haul roads.

HS2 CEO Mark Wild stands in front of the TBM Mary Ann at breakthrough in Birmingham

HS2 chief executive Mark Wild said: “Today’s breakthrough is a significant milestone for the project. Washwood Heath is set to become one of the most important sites on the entire HS2 network.”

The site will house HS2’s train depot and Network Integrated Control Centre. It’s also at the heart of a wider £10bn wave of regeneration and investment across the West Midlands.

More than 10,000 people in the region are now working on HS2, including 710 apprentices and 1,870 previously unemployed recruits. Over 400 local businesses are supplying the project.

Second TBM Elizabeth is now advancing through the parallel bore, due to complete later this year.

Tunnelling team at work

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Steve Rocke on his final tunnelling mission before retirement

Tunnelling apprentice Jevon Lynch from Birmingham

Gavin ‘Big Gav’ Davis at the wheel of the electric delivery vehicle inside the tunnel

Gary Jones, Ringbuilder

Family tunnellers: Father and son Greg and Dylan Kehoe

Josh Knight pictured inside the decompression chamber

Jules Arlaud, BBV’s Tunnelling Director

Pilot Harsh, skilfully navigates the tunnel boring machine under the River Tame

Glenn Race, PLC Technician, works alongside the pilot to keep the TBM running