Three rail workers had only seconds to react to avoid a London passenger train in a “near miss” in a commuter belt tunnel.
They were walking through Bookham Tunnel, near Leatherhead in Surrey, unaware that trains were still running on the track due to a mistake on the planning of the work.
The error meant they were in an “unsafe” position when the London to Guildford train suddenly appeared behind them travelling at more than 30mph.
They had just seconds to squeeze against the tunnel wall or get into a tunnel refuge.
One worker was only around a metre away from the train as it went past.
“Witness evidence indicates that due to the track curvature and because the train approached the group from behind, the track workers only had seconds to react when they became aware of the train,” said a report by the Rail Accident Investigation Branch (RAIB).
The RAIB inquiry told how the team of three track workers were walking through Bookham Tunnel, on the approach to Bookham station, at around 11.42am on April 29 2025.
They were unaware that the 10.54am South Western Railways service from London Waterloo to Guildford was heading towards them.
It was slowing down for a scheduled stop at Bookham station.
The driver suddenly saw the track workers ahead and sounded the train’s warning horn.
“Upon becoming aware of the approaching train, the track workers moved quickly to avoid it,” the report explained.
“Two of them moved into separate tunnel refuges (small alcoves in the tunnel wall) and the other stood against the tunnel wall as the train passed.”
It was travelling at 33mph as it went through the tunnel.
“Due to the track curvature, the sighting distance for the driver of the approaching train to the tunnel portal was approximately 150 to 200 metres, a distance which the train would have covered in 10 to 14 seconds based on the speed the train was travelling at the time,” the report added.
It explained that the near miss happened due to a mix-up in the work plans over two nearby tunnels, at Bookham and Mickleham.
“The track workers were walking in a different location to that which had been blocked to trains and that neither the track workers, nor the signaller who had granted the line blockage, had realised this,” the RAIB investigators concluded.
“This happened because the safe work pack, which formally detailed the safety arrangements for the task, incorrectly contained line blockage arrangements for the nearby Mickleham Tunnel, and not the tunnel around which the team was working.”
The report stressed that for line speeds below 100mph, a position of safety should be a minimum of 1.25 metres from the nearest running rail.
The distance between the tunnel wall and the nearest running rail of the down line where the track workers were walking was about 1.6 metres.
The “available space between the tunnel wall and the passing train” was between one and 1.15 metres.
Andrew Hall, Chief Inspector of Rail Accidents said: “Bookham Tunnel is one of a number of near misses that serve as a warning.
“Safety theory and bitter experience both tell us that a pattern of near misses will eventually end in tragedy, and that is what happened in Hertfordshire in March this year, where a track worker was struck and sadly lost their life.
“I know that work continues to try and reduce this risk further. Recent events show how urgent and important such work is."
