The west bore of the Dartford Tunnel closed for over two hours after a 50-tonne crane broke down and leaked oil onto the carriageway. Drivers faced severe delays as recovery and cleanup stretched well beyond the initial breakdown.
Recovery takes time with heavy vehicles
A specialist recovery team and National Highways officers worked on site to remove the crane. Moving a vehicle of this scale within an enclosed tunnel demands specific equipment and expertise. Access is controlled, and operations must carefully consider the tunnel’s ventilation and structural safety.
Oil spill creates safety risk
Removing the crane was only half the job. The oil leaking onto the road surface needed treatment before reopening the tunnel. Oil on carriageways reduces tyre grip. This is critical within tunnels where space is limited and drivers have no room to manoeuvre if traction is lost.
Traffic impact extended by spill treatment
National Highways reported delays lasting approximately two hours. Congestion extended back to Junction 3 of the M25, several miles from the tunnel itself. The closure also forced the shutdown of the J1a northbound slip road from Bob Dunn Way. Northbound traffic normally travelling through the west bore was diverted to the east bore, reducing capacity to one tunnel’s width for both directions.
Reopening is more than moving vehicles
Road surfaces contaminated by substances like oil require thorough cleaning before reopening, especially in tunnels. Unlike open roads, tunnels lack verges or multiple lanes to isolate compromised sections. This means safety checks and treatments can add significant time after vehicle recovery.
Delays persist after reopening
The tunnel eventually reopened once the surface was cleared. However, National Highways confirmed long delays remained as traffic backlog cleared. A road reopening does not mean immediate return to normal traffic flow. Clearing queues is a separate process with its own timeline.
