The construction works, due to start in January 2021, include an upgrade of the intersection of the M25 and A10 at Cheshunt to increase traffic capacity.
The project involves widening the 25 roundabout to four lanes, widening the M25 eastbound diverge and providing a segregated left turn for A10 northbound traffic, widening the westbound M25 diverge and widening the A10 southbound entry to the roundabout.
Up to 6,300 vehicles per hour usually travel through the junction 25 roundabout at peak times, causing congestion and regular delays. The A10 southbound approach into the junction is also a congestion hotspot in Broxbourne, Hertfordshire.
Graham was initially selected by Highways England back in 2018 for a place on its new regional delivery partnership for schemes below £100m
The Graham team, including consulting engineers Sweco and Fairhurst, was handed three junction improvement projects in the southeast: junctions 25 and 28 of the M25 and junction 5 of the M2.
The value of the M25 J25 contract has not yet been disclosed but the project page on Highways England’s website puts the overall cost at anything between £25m and £50m.
Graham highways director Dave Brown said: “This is another significant scheme for the southeast of England and we’re delighted to have been awarded the package by Highways England under the route to market regional delivery partnership.
“This scheme will reduce congestion and delays at junction 25 between the M25 and the A10 while also increasing capacity by widening both the roundabout and the A10 southbound approach.”