Train services from Moorgate to Finsbury Park in London were suspended after augers from piling work above broke through the tunnel lining.
Services were suspended after muddy water was reported to be pouring into the tunnel just north of Old Street Station this morning by the train driver of a Moorgate to Welwyn Garden City service. Two augers fell into the tunnel as a Network Rail mobile operations manager approached to inspect the area in an empty train travelling from Moorgate.
Services have been suspended while the Rail Accident Investigation Branch and British Transport Police carry out enquiries. Network Rail said specialist tunnelling contractors had been sent to the scene to assess the damage.
“Our engineers are on site assessing the damage and we will restore the railway as soon as possible,” said Network Rail route managing director Phil Verster. Repairs are expected to be carried out on the line - which does not operate at the weekend - in a bid to restore services by Monday.
Rail operator First Capital Connect (FCC) has praised the vigilance of the train driver. “This is a serious incident that could have ended very differently had it not been for the vigilance and prompt reporting and actions of our drivers,” said FCC managing director Neal Lawson. “We carry two million people a year on the Northern City Line and whoever is responsible for this must be held to account.”
British Transport Police has not named the piling contractor involved in the incident but FCC has said that the contractor was working on the foundations for a new office development.