The M25 Junction 10/A3 Wisley Interchange improvement scheme is a critical infrastructure upgrade designed to enhance traffic flow and improve safety at one of the UK’s busiest and most accident-prone motorway junctions. Led by Balfour Beatty, with design and engineering support from AtkinsRéalis, this major project involves widening the motorway, adding lanes to the A3, and constructing multiple new bridges—including the UK’s first heathland green bridge, Cockcrow Green Bridge.
As a key subcontractor on the project, Shay Murtagh was entrusted with the design, manufacture, and delivery of precast bridge beams for three major structures: Cockrow, Wisley, and Stratford Brook. Our scope included:
- Precision Engineering & Fabrication: Producing lifting and fabrication designs tailored for the project’s structural needs.
- Expertise in Precast Concrete Bridge Beam Manufacturing: Delivering high-quality precast concrete bridge beams to meet the project’s specifications.
- Efficient Delivery & Installation Support: Supplying on-site equipment, including shunters, jacks, and trestles, to facilitate seamless installation.
Our longstanding partnership with Balfour Beatty and proven track record in precast concrete bridge beam manufacturing were key factors in securing our involvement in this landmark project.
Among the structures delivered, Cockcrow Green Bridge stands out as the most significant. This 66-metre-long, 30-metre-wide bridge was installed over a single weekend closure, involving a 60-strong workforce operating in shifts around the clock. The structure comprises 22 precast W-type beams, each weighing 90 tonnes, designed to support a heathland corridor connecting Wisley and Ockham Commons.
This bridge forms a crucial link in a new 5km non-motorised user route, providing safer passage for pedestrians, cyclists, and equestrians. The innovative use of precast elements enabled a safer and more efficient construction process, reducing on-site work time and minimising disruption to one of the UK’s busiest road networks. Photos from the team at National Highways.



With decades of experience in precast concrete bridge beam manufacturing, Shay Murtagh delivers precision-engineered solutions for complex infrastructure projects. Whether you need high-performance bridge beams or a trusted partner for large-scale construction, our expert team is ready to assist. Contact us today to discuss your project requirements and discover how our innovative precast solutions can support your next development.