Engineers working on behalf of National Highways have widened the roundabout at the M25’s Junction 10 in Surrey, introduced a fourth lane on part of the A3 and built a green bridge across the A3.
The widening of the roundabout at J10 is designed to increase its capacity for traffic coming on and off the M25, and the fourth lane on the A3 is between J10 and adjacent junctions at Painshill and Ockham Park.
The bridge was described as “the UK’s first heathland green bridge” by National Highways, known as Cockrow Green Bridge, and connects Ockham and Wisley Commons, which are on either side of the A3, and is hoped to provide “a safe and natural corridor for wildlife”.
National Highways said the improvements were part of “a flagship project to reduce congestion, improve safety, and boost economic growth”, and said “Holidaymakers, day-trippers and sports fans” would benefit given the improved connectivity with ports, airports and sports venues.
NCE reported in October 2024 that Balfour Beatty was working on the upgrades at J10, valued at £317M.
J10 is between Heathrow and Gatwick airports, making it a “crucial strategic route” for people going on holiday and conducting business. Thousands of drivers travel to and from the airports every day, according to the highways body.
Both sections of road were restored to 70mph in 2025.
The A3 “regularly serving thousands of spectators at Sandown Park and Epsom Downs racecourses as well as the Great Britain Sail Grand Prix in Portsmouth,” National Highways said.
“Junction 10 and the wider M25 is a crucial artery that helps connect London and the South East to the rest of the UK and Europe, enabling the vital flow of goods and services.”
National Highways chief delivery officer Nicola Bell said: “The M25 is the heartbeat of the UK economy and offers a gateway to connect millions to airports, domestic holiday destinations and world-class entertainment this summer.
“Our Junction 10 upgrade has been a unique feat of engineering and involved us successfully managing a series of unprecedented full weekend closures of the M25.
“These improvements have helped support thousands of new homes and local jobs and allow us to provide safer, smoother journeys for all on these crucial routes.”
Heathrow Airport surface access director Sophie Chapman said: “As the world’s most connected hub and the UK’s largest port by value, Heathrow relies on strong, resilient transport links to connect people and UK businesses with markets across Britain and around the world.
“The improvements to Junction 10 are a significant upgrade for one of the airport’s key transport links and one of the UK’s most important road corridors.”
She added: “Projects of this scale inevitably require careful planning, but the result is a more reliable network that supports economic growth and keeps people and freight moving.”
London Gatwick head of surface access strategy Richard Higgins said: “We are pleased to see the successful delivery of this investment in strategic, nationally significant infrastructure.
“The M25 is important to the whole of the South East, including many passengers and staff that travel to and from the airport.
“These improvements provide better journey time reliability and greater certainty for road users, whether that’s passengers catching their flights for business trips and holidays abroad or colleagues working at London Gatwick keeping the airport running smoothly 24/7.”
Road Haulage Association director of external affairs David Boot said: “We welcome road projects that will provide smoother, more efficient journeys across the supply chain. This is a nationally strategic stretch of road which acts as a key route for hauliers and coach operators from Kent ports to much of the rest of the country.
“With over 80% of Britain’s goods moved by road, a safe, resilient and fit-for-purpose network is essential to our industry and to wider economic growth. We look forward to seeing further investment of this kind.”
UK Major Ports Group CEO Geraint Evans said: “Our ports allow British business to thrive and bring in goods we all depend on in our daily lives – but this only works if the whole country is properly connected.
“The M25 is essential to connecting some of the UK’s busiest ports to the rest of the UK, ensuring that supply chains keep moving. We’re therefore delighted to see the improvements at Junction 10 delivered, providing quicker, safer, and more reliable journeys for years to come.”
Logistics UK acting policy director Ben Garratt said: “The smooth completion of the M25 Junction 10 works will enable freight to continue to move effectively across this busy section of the orbital motorway, connecting businesses across the south and west with the rest of the country, and demonstrates what can be achieved with close cooperation between industry and government agencies.”
In August 2025, NCE reported that Balfour Beatty has started construction of the new Clearmount footbridge near M25 J10.
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Facts Only
* Engineers worked on behalf of National Highways.
* The roundabout at M25 Junction 10 was widened.
* A fourth lane was introduced on part of the A3 between J10 and adjacent junctions at Painshill and Ockham Park.
* A green bridge, named Cockrow Green Bridge, was built across the A3.
* The bridge connects Ockham and Wisley Commons.
* The widening increased capacity for traffic on and off the M25 at J10.
* The improvements were part of a project to reduce congestion, improve safety, and boost economic growth.
* Balfour Beatty was working on the upgrades at J10, valued at £317 million.
* Junction 10 is situated between Heathrow and Gatwick airports.
* Both road sections were restored to 70mph in 2025.
* The A3 regularly serves spectators for events like Sandown Park and Epsom Downs racecourses and the Great Britain Sail Grand Prix.
Executive Summary
Full Take
The narrative centers on infrastructure development framed through economic and connectivity lenses. The project is presented as a 'flagship' endeavor, linking physical engineering with abstract goals of growth, safety, and mobility for diverse user groups—from business travelers to sports fans. This framing serves to legitimize significant public expenditure by connecting tangible construction work (widening, bridge building) directly to broad national economic benefit. The contrast between the immediate local impact (J10 traffic management) and the wider strategic significance (M25 as an artery for goods, airport connectivity) reveals a tension between localized needs and macro-level imperatives. The voices quoted emphasize how this infrastructure supports systems—logistics, transport, and economic flow—suggesting that physical works are accepted if they demonstrably facilitate these large-scale operations. The implication is that modern infrastructural solutions are necessary conduits for capital and movement, but the cost distribution and specific impacts on local communities (beyond the named corridors) remain unexamined in this public framing.
What assumptions about the primacy of economic growth over localized environmental or social impact drive the justification for such massive infrastructure projects? How do the diverse stakeholder appeals—airport directors, logistics bodies, and general road users—collectively attempt to establish a unified definition of 'improvement' when the metrics (journey time reliability versus wildlife corridors) are inherently different? What alternative metrics should be prioritized when balancing national economic goals against the stated environmental benefits associated with the new green bridge?
Sentinel — Human
The article reads like a standard, fact-based infrastructure report that effectively synthesizes official statements regarding a specific engineering project and its broad economic impact.