The final deck segment for HS2’s Delta Junction viaduct system has been manufactured, marking a major milestone in building one of the railway’s most complex structures near Birmingham.

More than 2,700 precast deck segments have been produced for the triangular network of viaducts at Delta Junction.

Each unit weighs up to 85 tonnes and was made at a temporary facility beside the M42 near Kingsbury, Warwickshire. After production, the segments are transported by road to nearby sites where they are lifted into place to form the viaduct spans.

Delta Junction is one of the most technically demanding parts of the high-speed rail project, carrying the railway across a dense network of motorways, roads, railways, rivers and floodplains. Two major viaduct systems, at Coleshill and Water Orton over the River Thame, are being assembled using these segments.

Around three-quarters of the 2,742 segments produced so far have already been installed. Teams have completed deck assembly for the Coleshill viaducts and finished key spans of the Water Orton 1 and Water Orton 2 viaducts crossing the A446.

With deck segment production complete, the Kingsbury factory will now switch to manufacturing other precast components, including deck slabs for the Curzon Approach viaducts leading into Birmingham city centre.

“Casting these enormous segments on site, close to the viaducts, helps us deliver a quality product and reduce disruption for road users. It’s great to see the final segments complete and I’d like to thank everyone involved in the manufacturing process.

“With this part of the work finished, the team can begin to focus on the deck slabs for the approach viaducts which will carry the railway into central Birmingham.”

Caroline Warrington, HS2 Ltd’s Head of Delivery.

“Watching the final segment roll off the production line at our precast yard in Warwickshire was a huge moment for the team. We’ve successfully delivered 2,742 viaduct segments over three-and-a-half years – an incredible achievement that we can all be proud of.

“This outdoor facility will now be repurposed to produce over 1,200 concrete deck slabs that will help form the Curzon Approach viaducts, using the same highly skilled and experienced team.”

Laura Arrieta, BBV’s team leader for Kingsbury.