The Severn Tunnel’s overhead conductor system has deteriorated after being installed as part of an £10M upgrade less than two years ago.
Transport minister Jo Johnson revealed that the overhead conductor system, which was installed in 2016, is showing “early signs of deterioration”, which must be fixed before further electrification work can take place.
“The overhead conductor system is showing early signs of deterioration because of the wet and corrosive environment in the Severn Tunnel,” Johnson said in a written parliamentary response to Nick Smith MP.
“Network Rail has identified this early on and are addressing this matter prior to energisation of the electrification system.”
Smith, the Labour MP for Blaenau Gwent, said the situation was “hopeless”.
“Anyone needing to get from South Wales to London has to put up with longer journeys and major disruption all because Network Rail failed to keep their kit in proper condition from the get-go,” he said.
“The new equipment has got to be safe to use from the start, so it beggars belief these problems weren’t picked up on sooner.”
Network Rail said maintaining the equipment involves cleaning the conductor beam system. This will now now form part of its annual tunnel maintenance programme.
A Network Rail spokesperson said: “The Severn Tunnel and Patchway tunnels in Bristol are closed for three weeks so engineers can deliver essential modernisation and electrification work on the Mainline in Bristol and South Wales.
“The work in the Patchway tunnels involves lowering the track to accommodate the overhead line equipment needed to power trains running on electricity.
“In order for engineers to safely carry out this work, the Severn Tunnel must also be closed to trains. We are taking this opportunity to build on the modernisation work delivered in the tunnel during autumn 2016, including maintaining the new equipment and drainage system and removing redundant cables and telecoms equipment.”
The tunnel, which connects England and Wales, has been closed two weeks for electrification works, and is due to re-open on Saturday.
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