Drivers faced major disruption on the M25 after a crash, and an earlier vehicle fire forced closures and triggered diversion routes across key sections of the motorway.
The incidents led to long queues, heavy congestion, and significant delays during peak travel hours.
Authorities redirected traffic onto alternative routes, causing additional pressure on nearby roads and extending journey times for commuters across the region.
M25 Traffic Update: Road Reopens but Delays Remain
Authorities later confirmed that affected sections of the motorway had reopened. However, residual delays continued as traffic slowly cleared. Officials warned that congestion could take time to ease fully, especially given the earlier diversions and backlog of vehicles.
M25 Traffic: Crash Sparks Rush-Hour Delays
A collision on the M25 clockwise between Junction 12 (London) and Junction 13 (Windsor) caused immediate disruption during the morning rush hour. Lanes were blocked as emergency services attended the scene, leading to long queues and slow-moving traffic.
The incident quickly escalated into a major traffic issue, with congestion building as vehicles were forced to slow down or stop completely.
M25 Traffic: Six Miles of Congestion Reported
Traffic built up to around six miles on the approach to the affected stretch, with delays of up to 30 minutes reported. The scale of congestion highlighted the impact of even a single incident on one of the UK's busiest motorways.
Traffic cameras showed long queues stretching back across multiple junctions as drivers attempted to navigate the disruption.
M25 Traffic Update: Full Diversion Routes
Drivers were advised to follow the hollow triangle diversion symbol on road signs. The official diversion route is:
- Exit the M25 at Junction 20 (Hemel Hempstead)
- At the roundabout, take the 4th exit onto the A41 towards London
- Continue on the A41 towards Watford
- At the A41/A405 Leavesden Green junction, take the exit slip onto the A405
- Follow the A405 towards St Albans
- Rejoin the M25 at Junction 21A
- At the roundabout, take the 3rd exit back onto the M25 clockwise
M25 Traffic Diversion Routes Cause Heavy Local Congestion
The diversion routes quickly became congested as traffic was redirected off the motorway onto smaller roads. Areas around Watford, Leavesden, and St Albans saw a sharp increase in traffic, leading to further delays.
Commuters reported slow-moving traffic and extended journey times as local roads struggled to handle the additional vehicles, particularly during peak hours.
M25 Traffic Update: Emergency Services & Official Advisory
Emergency services responded promptly to the incidents, working to clear the crash and manage traffic flow. Despite their efforts, the scale of disruption meant delays continued for several hours.
A spokesperson for National Highways said, "If this closure impacts your planned route, please allow extra journey time. Plan, you may wish to re-route or even delay your journey."
M25 Traffic: Vehicle Fire Led to Overnight Closure
Earlier, a heavy goods vehicle fire forced the closure of another section of the M25 between Junction 20 (Hemel Hempstead) and Junction 21 (M1). The motorway remained shut for over 10 hours as crews carried out emergency resurfacing work due to damage caused by the fire.
This earlier incident added to the disruption, making conditions more difficult for drivers already dealing with the crash-related delays.