Video | National Highways Lower 25t Gantry From Prince of Wales Bridge

Key Takeaways

• 25‑ton gantry removed 40 m onto barge for recycling
• First gantry removal from bridge since its 1996 construction
• Replacement needed after 27‑year service, beyond typical 20‑35 year lifespan
• National Highways partnered with Amey and Denholm for complex lift
• New gantry design slated for installation within current financial year

Pulse Analysis

The Prince of Wales Bridge carries the M4, the main east‑west artery between England and Wales, over the River Severn. Built in 1996, the structure now faces the same ageing challenges that affect much of the UK’s motorway network, where many assets were erected in the post‑war boom and are approaching the end of their design life. One of the most visible maintenance tools is the overhead gantry, used for lane closures, signage and inspection equipment. After roughly 27 years of service, the gantry had exceeded the typical 20‑35‑year lifespan, prompting a full replacement rather than costly repairs.

The removal operation required a specialist team from National Highways, Amey and Denholm Industrial Services. Engineers lowered the 25‑tonne steel framework in two sections, guiding it 40 metres onto a waiting barge while a few workers remained attached for safety. The reverse of the original 1996 installation, the lift demanded precise load calculations, weather monitoring and coordination with river traffic. Once on the barge, the gantry was taken to a recycling facility, turning a massive steel structure into reusable material and reducing landfill impact.

Replacing the gantry signals a broader commitment to keep the M4 fit for purpose as traffic volumes rise and climate‑related stresses intensify. The new design, currently in the engineering phase, aims to incorporate lighter materials and modular components that can be installed more quickly and maintained with minimal disruption. For the construction sector, the project showcases how legacy infrastructure can be modernised through collaborative planning and sustainable disposal practices, setting a benchmark for similar upgrades across Britain’s aging highway system.