26 October 2026, near Chelmsley Wood, UK — HS2 Ltd and its construction partner Balfour Beatty VINCI completed installation of the second M6 viaduct west deck above the north and southbound carriageways at junction 4/4a of the M6. HS2 Ltd said the final section of the 4,750-tonne structure was launched using giant hydraulic jacks while traffic remained open beneath, completing both parallel M6 South viaducts. The east deck was completed in 2025; the west deck was moved into place on Saturday, 24 October 2026. Both viaducts are 320 metres long, constructed from weathering steel, set on concrete piers and sit 100 millimetres apart.
According to the report, the west deck launch took nine hours, moved 76 metres at an average speed of 12 metres per hour, and was executed in four incremental launches using strand jacks. The east deck was launched in three stages. The M6 remained open throughout; the M42–M6 link road was closed to provide a safety exclusion zone and reopened at 21:00 on 24 October 2026, 25 hours ahead of schedule. HS2 Ltd said parapet works at Water Orton above the M42 were postponed due to strong winds and rescheduled for 30 October–2 November 2026. HS2 said motorway works in 2027 will focus on the Coleshill triple box, with scheduling coordination involving National Highways.
Lead
26 October 2026, Chelmsley Wood, UK — HS2 Ltd reported completion of the installation of the west deck of the M6 South viaducts above the M6 motorway at junction 4/4a. The work was carried out by HS2’s construction partner Balfour Beatty VINCI and completed while traffic continued to flow beneath the structure.
Verified facts
HS2 Ltd said the final section of the 4,750-tonne structure was launched above the north and southbound carriageway (junction 4/4a) of the M6 using giant hydraulic jacks. The west deck was moved into place on Saturday, 24 October 2026. The east deck, which will carry high-speed trains towards Old Oak Common and Euston, was completed in 2025; the west deck will carry trains towards Curzon Street Station and destinations in the north, including Manchester, Liverpool and Glasgow. HS2 Ltd revealed that the two parallel structures are 320 metres long each, constructed from weathering steel, stand 100 millimetres apart and are supported by a series of concrete piers. Raised embankments will be formed either side of the viaducts.
The report stated that the west deck was launched in four incremental stages and the east deck in three. For each launch, additional steel sections are added to the rear of the structure and the whole deck is propelled forward using strand jacks; by the final launch the steel deck is fully supported on concrete piers, enabling the last push to be executed while traffic flows continue. The west deck launch took nine hours, during which the steel deck moved forward 76 metres at an average speed of 12 metres per hour. The M6 remained open throughout the weekend. The M42–M6 link road was closed to provide a safety exclusion zone and reopened at 21:00 on Saturday, 24 October 2026, 25 hours ahead of schedule.
HS2 Ltd also reported that Water Orton viaduct parapet installation works above the M42 were postponed due to strong winds and rescheduled to the following weekend. The report sets closure dates for that programme as J6 to 9 northbound and J9 to 7 southbound from 21:00 on Friday, 30 October to 05:00 on Monday, 2 November 2026. Looking ahead, HS2 said the motorway construction programme in 2027 will centre on the triple box carrying four HS2 tracks over the M42 near Coleshill and that HS2 is working closely with National Highways to agree the schedule of works.
Organizations and responsibilities
HS2 Ltd: reported as the project owner or programme lead that provided details of the structure, dates, weights, materials, operation method and future schedule; HS2 Ltd issued the statements contained in the report. Balfour Beatty VINCI: identified in the report as HS2’s construction partner and as the delivery organisation executing the launches; the report attributed specific delivery activity and timing to Balfour Beatty VINCI, including that engineers working for Balfour Beatty VINCI completed the final launch in nine hours. National Highways: identified by HS2 Ltd as a coordination partner for agreeing the 2027 motorway works schedule. Other participants, suppliers, contract values and ownership details: Not publicly disclosed.
Operational and commercial context
According to the report, the engineering approach used incremental launches with strand and hydraulic jacking to complete the viaduct decks while maintaining traffic flow on the M6. HS2 Ltd said this method minimised disruption for motorists and allowed the final push to be made once the steel deck was supported by concrete piers. The report indicates the completion of both M6 South viaducts removes a major programme risk above a busy motorway corridor and that subsequent motorway work will include parapet installation at Water Orton and the 2027 triple-box works at Coleshill, subject to schedule agreement with National Highways. The report attributes statements about programme progress, community impact and safety considerations to HS2 Ltd and to Balfour Beatty VINCI personnel. Any implications for contract values, project ownership beyond HS2 Ltd and Balfour Beatty VINCI, long-term delivery timelines beyond the firm dates disclosed, or commercial impacts on third parties: Not publicly disclosed.
Sources
https://news.railbusinessdaily.com/hs2-completes-installation-of-second-m6-viaduct/ — Rail Business Daily (source organisation as published)
Disclosure
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