8th Apr 2024

Colne Valley Viaduct crosses Grand Union Canal

The construction of the Colne Valley Viaduct for HS2 reaches another milestone as the UK’s longest railway bridge crosses the country’s longest canal.

Twenty first and eighteenth centuries meet as HS2 traverses Grand Union Canal

New images and video show the most recently-completed section of HS2’s Colne Valley Viaduct after deck segments were laid to span the Grand Union Canal near Denham.

They juxtapose the new 140-mile high speed London-Birmingham railway against the eighteenth century’s solution to connecting Britain’s two largest cities.

Both were built under powers granted by Act of Parliament; arrive in the Birmingham district of Digbeth; and with similar lengths – HS2, 140miles; the canal, 137 miles – were two of the largest civil engineering endeavours of their time.

The two differ dramatically in other respects. Compared to the sedate progress of canal boats high speed trains will travel across the 2.1mile viaduct at speeds of up to 200mph, completing the journey between the capital and Britain's second city in just 49mins.

Uniquely shaped and weighing as much as 140 tonnes, 755 of the viaduct's 1,000 deck segments have been installed creating 39 spans over land and water for 1.5 miles. News comes after construction of all the viaduct's 56 supporting piers was completed in advance of the deck being installed above.

Once complete, HS2 will provide faster and far more reliable journeys between London and Birmingham, with trains running on conventional lines further north. It will also double rail capacity between the UK’s two biggest cities – relieving the most congested southern part of the West Coast Main Line, creating more capacity for local and freight services.

HS2 Ltd senior project manager Billy Ahluwalia, said: “I pay tribute to the tremendous dedication and professionalism of the whole team who’ve maintained high standards of safety and quality, working over land and water, come rain or shine to deliver the viaduct’s 56 piers along a 2.1-mile stretch of HS2’s route. Their remarkable achievement will be for all to see across this century and well into the next.

“Our work to install the viaduct’s remaining deck segments continues at pace, followed by the installation of the deck edge parapets and noise barriers, before we hand over to Rail Systems for the next major phase of the build programme.”

Viaduct construction is led by HS2’s main works contractor Align JV – that includes Bouygues Travaux Publics, Sir Robert McAlpine and Volker Fitzpatrick.

HS2’s longest viaduct crosses 18th century Grand Union Canal

  • Building an Infrastructure Legacy

    From the pioneering railways and viaducts of the Victorian era constructed by our founder, we continue to build on our legacy of infrastructure projects with the delivery of today’s essential highway and rail networks.

    Find out more

Latest Infrastructure news

  1. Unique HS2 tunnel portal completed

    25 Apr 2025

    Our Align JV builds tunnel extensions for HS2 to stop sonic booms from 200mph trains entering the 10-mile Chiltern Tunnel.

    Read more about
  2. A19 Tees Viaduct project scoops Bridges award

    31 Mar 2025

    The A19 project team wins the Ethos award for excellence in wellbeing, training, and community engagement.

    Read more about
  3. Stamp it Out briefing

    24 Mar 2025

    The Stamp it Out briefing, chaired by our Managing Director of Transport, Vip Gandhi, along with Safer Highways CEO, Kevin Robinson, received a ministerial seal of approval at a special Summit held in London

    Read more about

Latest news

  1. Unique HS2 tunnel portal completed

    25 Apr 2025

    Our Align JV builds tunnel extensions for HS2 to stop sonic booms from 200mph trains entering the 10-mile Chiltern Tunnel.

    Read more about
  2. Annual Report and Accounts 2024

    24 Apr 2025

    Download the Annual Report and Accounts that accompany our financial results 2023-24.

    Read more about
  3. SRMCV and Buccleuch acquire 101 Centre Street, Glasgow

    16 Apr 2025

    Sir Robert McAlpine Capital Ventures and Buccleuch Property acquire 101 Centre Street, securing income and unlocking major redevelopment potential in Glasgow's southbank.

    Read more about
View all news