The tunnel boring machine (TBM) Elizabeth broke through the final Birmingham tunnel – the 3.5-mile Bromford tunnel – on 13 October.
Launched 19 months ago near Water Orton, a village in Warwickshire, it arrived yesterday at Washwood Heath.
This breakthrough marks the completion of major tunnel excavation between Old Oak Common (London) and the West Midlands. The tunnel in question runs underneath the M6.
The 125m TBM, named after Elizabeth Cadbury, a 19th century philanthropist, was launched in March 2024. Its counterpart, which dug the other twin bore, was Mary Ann. It broke through earlier this year.
Together, the two TBMs have excavated more than 1.8 million tonnes of material and fitted 5,804 concrete ring segments for the east and westbound tunnels.
In total, 28 miles of the route between Old Oak Common and Birmingham Curzon Street will be in tunnels. Construction teams will now focus their work on internal walkways, ventilation shafts and cross passages.
The work on the tunnels has been a positive milestone but other aspects of the infrastructure project – which is set to free up space on the existing West Coast Main Line for more local services and freight – are behind.
HS2 Ltd Chief Executive, Mark Wild is trying to action a comprehensive reset of the programme to deliver the railway in the most efficient way possible and for “the lowest reasonable cost” – in the face of countless political obstacles since its inception.
AlanToday’s breakthrough is a major milestone for the tunnelling team here in Birmingham and for the HS2 project. All eight of the TBMs digging our tunnels between Old Oak Common and Curzon Street have now broken through, which means that the focus is now on the internal concrete work, ventilation shafts and cross passages.
I’m immensely proud of the men and women who have worked round the clock to bring our TBMs and their crews home safely, and I look forward to seeing more progress inside the tunnels in the years ahead.
The average speed of the TBMs working on the HS2 project is 10 metres per day. So far, a total of 8 tunnel boring machines have been used. Two more are expected to launch in 2026, to dig the tunnels between Old Oak Common and HS2’s final destination, London Euston.
Now that the breakthrough of Elizabeth is complete, the TBM will now be removed from the tunnel to allow work to proceed on the finishing works, base slabs and emergency and maintenance walkways.
Washwood Heath will be one of three key sites for HS2 in the West Midlands, alongside the two new stations in Birmingham and Solihull. HS2’s Depot and Network Integrated Control Centre will be built next to the tunnel portal. It’s from this site that trains will be serviced and stored and the real-time operation of the line controlled.
