Scheme at a glance

Scheme at a glance

The M25 junction 28 plays a huge role in connecting the A12 and the M25, as well as providing access to Brentwood via the A1023. Up to 7,500 vehicles pass through the junction roundabout at peak times.

As it is operating at capacity, vehicles using the junction face congestion and delays, which effects local air quality. Our research shows that traffic is expected to increase in the area by around 30% by 2037, which means that over 9,000 vehicles could be passing through it by this date.

Our improvement scheme will:

• increase capacity and reduce congestion at the junction and on the approaches and exits
• improve safety by redesigning the existing roundabout layout and reducing traffic levels
• provide better connections between the M25 and A12
• reduce annual collision rates through additional capacity
• improve average journey times and reliability for all passing traffic through the junction
• minimise the impact of air and noise pollution in the local area by smoothing the traffic flow
• reduce traffic queuing back onto the M25
• help economic growth in the area by providing improvements to cater for future traffic demands

Our improvements

During main construction we’ll be:

• building a new two-lane loop road, for traffic travelling from the M25 anti-clockwise onto the A12 eastbound (towards Brentwood). This will include the construction of new bridges to take the loop road over or under the other road links, and the Weald Brook; new signage and changes to the landscape
• changing the position of A12 eastbound exit slip road and M25 anti-clockwise entry slip road to allow for the new loop road
• widening the M25 anti-clockwise carriageway to provide more space for traffic leaving for the A12 eastbound

(Visualisation of our improvements)

Length of the scheme

We expect that the main construction work will last around two and a half years, with the scheme open for traffic in summer 2025. The programme has been developed to minimise disruption to all road users and stakeholders.

Road closures

Most of our construction will take place off the road network, with the new loop road and links being almost fully built before we need to do any major work that will impact drivers.

We’ll still need to have some closures. These will be when we link the new roads to the existing network, and while we’re working on the gantries and signage. Any closures will be planned to minimise impact on drivers, with advance notice will be given through our project website and social media.

(Proposed improvements)