The Oxford Canal viaduct on the HS2 route has reached a significant construction milestone, with bricklayers completing the installation of distinctive ironstone cladding that will define the appearance of the structure for generations to come.
Blending traditional building materials with modern engineering, the locally sourced ironstone has been used to clad key elements of the viaduct, creating a visual link between the new high-speed railway and the historic canal environment it crosses near Wormleighton, on the border of Warwickshire and West Northamptonshire.
Known for its durability and warm brown colour, ironstone has featured in local buildings for centuries, including the nearby Church of St Peter in Wormleighton. The stone derives its name from the naturally occurring iron ore found within it and was selected following consultation with local communities.
The viaduct itself consists of three reinforced concrete spans stretching 62.5 metres across the Oxford Canal, its towpath and an adjacent country lane. Designed to sit low within the landscape, the structure has been developed to minimise visual impact while maintaining open views for canal users and visitors.
As construction of the main structure nears completion, attention has focused on the architectural detailing around the piers and abutments facing the canal. During the design process, local residents were invited to choose between a smooth concrete finish and a rough-cut masonry appearance. The majority favoured the ironstone option, reinforcing the project's connection to the canal corridor's heritage.
To minimise disruption to navigation, the cladding sections alongside the canal were assembled by hand before being lifted into position. Installation around the two viaduct piers required specialist craftsmanship, with experienced bricklayers spending four weeks placing approximately 2,000 individual stone blocks around the concrete cores. Many blocks had to be cut and shaped to match the complex geometry of the structure.
HS2 Ltd’s Senior Project Manager, Sam Arrowsmith said:
"More than two hundred years ago, the first canals revolutionised transportation and helped to build the country we live in today so it’s fitting that our contemporary design includes a nod back to those eighteenth-century pioneers."
"Once complete, HS2 will transform journeys across the UK, provide more capacity on the existing rail network and help to boost the economy. But it’s also important that key structures like the Oxford Canal viaduct are sensitive to their location, which is why we’ve opted for the ironstone finish."
Beyond the use of local materials, the viaduct has been designed to enhance the experience of walkers and boaters by creating a light, open structure that preserves views across the surrounding countryside. The approach reflects a broader focus on ensuring major railway infrastructure is integrated sensitively into its environment.
The Oxford Canal viaduct is one of 15 bridges and viaducts being delivered by HS2’s main works contractor EKFB, a consortium comprising Eiffage, Kier, Ferrovial and BAM Nuttall. The project team has worked closely with architects Moxon and design partners ASC, which includes Arcadis, Setec and Cowi.
EKFB Project Director, Alexei Bond, said:
"The installation of the ironstone cladding marks a significant milestone for the Oxford Canal viaduct, giving the structure its distinctive character which reflect the heritage of the canal corridor. As the project progresses, our focus is now on completing the embankments, landscaping and environmental works that will help the viaduct settle naturally into the surrounding landscape."
"The feedback from our local communities has been central to our approach from the outset. As part of our commitment to being a good neighbour, the ironstone cladding used on the viaduct's piers was chosen through community engagement, allowing local people to help influence the structure's final appearance and ensuring it complements the character of the surrounding area."
Throughout construction, HS2 has worked closely with the Canal & River Trust to minimise closures and keep canal users informed. No water was drawn from the canal network during the works, while a temporary construction bridge linking sites on either side of the canal has now been removed.
With completion of the viaduct approaching, project teams are preparing to begin embankment construction, landscaping, drainage installation, fencing works and restoration of the currently diverted towpath. HS2 is also working with the Canal & River Trust to restore a nearby historic bridge carrying a farm track and public footpath across the canal.
Opened between 1774 and 1790, the 75-mile Oxford Canal remains one of Britain’s oldest waterways. Originally built to transport coal from the Coventry coalfields to Oxford and the River Thames, it has since become one of the country's most popular leisure waterways.
Image credits: HS2
