M25 Junction 10/A3 Wisley interchange improvement scheme
Surrey, UK · 2022–2026 (estimated completion) · £317 million
The judgement call
Account-gated at launchFocus on heathland restoration and environmental improvements alongside road upgrades. - Early completion of key elements like the RHS Wisley bridge to facilitate access. - Collaboration with local students for design elements (Cockcrow Bridge). - Use of temporary road layout changes to manage traffic flow during construction.
Key engineering challenges
Managing traffic flow on one of the busiest sections of the M25 (300,000+ vehicles daily) during construction. - Constructing complex new structures and widening existing roads within a constrained and environmentally sensitive area (heathland). - Integrating new infrastructure with existing road networks while minimizing disruption. - Ensuring safety for workers and road users throughout the construction period.
Project facts
- Client / owner
- National Highways
- Lead contractor
- Balfour Beatty
- Lead designers
- AtkinsRéalis (formerly Atkins) (involved in bridge design/trial)
- Project type
- upgrade
- Scale
- Widening of A3 to 4 lanes in both directions; larger roundabout with extra lanes; new slip roads; new dedicated bridge into RHS Garden Wisley.
- Disciplines
- civil; structural; geotechnical; environmental; intelligent transport systems
- Standards & frameworks
- DMRB; NEC4; CDM Regulations
Sources: National Highways (https://nationalhighways.co.uk/our-roads/south-east/m25-junction-10/) - Balfour Beatty (https://www.balfourbeatty.com/what-we-do/projects/m25-junction-10-a3-wisley-interchange-improvement-scheme/) - BBC News (https://www.bbc.com/news/articles/cq5q9vgq6q5o)