The west deck of the M6 South viaduct, which will carry high speed trains towards Birmingham, is being assembled in four sections. The first 107 metre section will be slid over the M6 junction 4 southbound slip road on 11th April 2026.
The engineering team from Balfour Beatty VINCI, HS2’s contractor in the West Midlands, forecast that it will take just two days to safely manoeuvre the 1250-tonne weathering steel structure into place. Using the tried and tested slide technique, a giant hydraulic jack will pull the viaduct over the concrete piers, 102 metres away, where it will then be locked into position.
The slip road will close at 5am on Saturday, 11th April for the slide to begin. The viaduct is expected to be in position by Sunday evening and the 45-strong crew leading the operation will conduct final safety checks ahead of the slip road’s planned reopening at 10pm on 12th April.
The 320-metre-long West deck will be positioned parallel to the East deck, which was safely installed over the M6 in three stages in 2025. The final stage of the East deck installation was a UK-first in civil engineering, with the main carriageway remaining open and traffic flowing below as the viaduct was slid into place.
Having successfully achieved this engineering feat, HS2 has once again worked collaboratively with its partner, National Highways, to undertake further stages of the West deck viaduct slide without closing the carriageway underneath.
Ian Clarke, HS2 Ltd’s project manager for the M6 works, said:
“After safely completing the first viaduct on time, our engineers have wasted no time in forging ahead with the second installation.
“Thanks to the world-class engineering techniques we’re adopting on HS2, we’ve once again been able to reduce the number of temporary closures on the motorway while we carry out these essential works.”
The viaduct’s West deck has posed additional construction challenges for BBV’s civil engineers. The East deck was constructed and installed in three stages, but the West deck requires an extra stage. Space constraints, coupled with the staggered nature of the abutments (which the viaduct rests on) and the curve of the loop road, mean the team has a shorter launching platform, so the viaduct must be assembled in four smaller sections.
Russell Luckhurst from Solihull is the BBV civil engineer leading the works. At just 28, and with a UK-first already under his belt, he and his team are now undertaking final preparations ready for the second viaduct launch to begin.
The launching nose, which will guide the structure, is now affixed and the team is focused on assembling the propulsion system – the cables and jacks required to move the structure forward.
Russell, said:
“Building on the success of installing the East deck viaduct last year, we’re gearing up for the first launch of the neighbouring West deck in April.
“We’re using the same sliding technique, where a giant hydraulic jack will push the viaduct across the motorway in multiple stages throughout the year. The previous launches provided the team with invaluable experience, which they’re eager to apply to future works on this eye-catching structure spanning the M6.”
The West deck installation marks the start of an intensive programme of work that will take place this year to construct the high-speed railway over the West Midlands motorway network.
While the M6 will remain open to vehicles in June, during the second stage of the West deck installation, BBV engineers will start a complex programme of work on the M6 and M42 during the summer months. HS2 Ltd is working with National Highways to finalise the schedule of works.
Kamaljit Khokhar, National Highways Midlands Head of Planning and Development said:
“The impact of these major construction works on the people who use our roads is always our focus and we will continue to work with HS2 and their partners to ensure both the safety of road users and that disruption is kept to a minimum while this second viaduct is put into place.
“We are very supportive of any initiatives which will reduce disruption for drivers and local communities and welcome the innovation being displayed by HS2 to keep the number of closures required to a minimum.”
While the M6 works demonstrate progress is being made, there is still a vast amount of work to do across the 140-mile route between London and Birmingham. Mark Wild, HS2 Ltd Chief Executive, is leading a comprehensive reset of the project to ensure the remainder of the route is delivered as efficiently as possible and for the lowest reasonable cost.
Image credit: HS2 Ltd
