Network Rail has announced that it has finished work to stabilise a Chalk embankment that failed and caused a train to derail and collide with another train in September 2016.
An investigation of the incident by the Rail Accident Investigation Branch led to Network Rail being urged to fast track its drainage asset mapping.
No one was injured and it took just one weekend to clear the trains but it has taken a further 14 months to remediate the slopes to prevent future failures.
The £4M repairs involved removing all vegetation from the site so that 1km of rock netting and soil matting could be secured using more than 500 rock anchors.
“Passengers will have more reliable journeys through the Watford area thanks to this investment,” said Network Rail scheme project manager Gavin Evans. “The challenge was to work safely around the operational railway without impacting on journeys. A large proportion of the work took overnight and at weekends and the work we have done will protect the cutting for more than 60 years.”