A key portion of the M25 will be closed for a number of weekends as important upgrade work begins, with drivers braced for potentially huge delays to their journeys.
National Highways will have to stop motorists using the M25 junction 28 clockwise exit slip road for seven weekends so work can begin on a gantry base.
The stretch between the M25 and A12 near Brentwood, Essex will be off-limits so the upgrade can be carried out safely.
The next closure will be on Friday at 11pm until 5am next Monday Monday. A signed-posted diversion will be in place via the M25 J29 and returning on the anticlockwise carriageway.
The junction will then be closed the following weekend weekend, from 11pm on September 13 until September 16 at 5am. It’s not yet been confirmed when the other five closures will take place.
To get to the M25 J28 interchange from the M25 clockwise during the closure, drivers will have to continue on the M25 clockwise before exiting at junction 29, and returning to junction 28 by the M25 anticlockwise.
The works are intended to increase capacity and reduce congestion at the junction, improve safety by changing the current roundabout levels, and smooth the flow of traffic, thereby minimising local air and noise pollution.
In its explainer about the works on its website, National Highways said the approach they were taking to the closure was the best of the options available.
It said: “We’re moving to the next phase of our works – building the new gantry base. We’ve chosen weekend closures as the least disruptive option for road users.
“Other options, like putting continuous traffic management in place for several weeks, would cause more inconvenience to people at peak times.
“J28 plays a huge role in connecting the A12 and the M25 and provides 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,” the explainer reads.
“Our research shows that traffic is expected to increase in the area by around 30 per cent by 2037, which means that over 9,000 vehicles could be passing through it by this date.”
The scheduled improvements include:
- the construction of a new two-lane loop road for traffic travelling from the M25 anti-clockwise onto the A12 eastbound towards Brentwood
- changing the position of A12 eastbound exit slip road and M25 anti-clockwise entry slip road to allow space for the new loop road
- widening the M25 anti-clockwise carriageway to give more space for traffic leaving for the A12 eastbound
The project is estimated to cost between £120 million and £170 million, as per the Evening Standard.