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

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