Engineer warns tube tunnel damage may keep lines closed for weeks

It could take as long as eight weeks for the tunnels damaged in last Thursday’s London terrorist attacks to be operational again, disaster recovery experts have warned.

Dr Philip Esper, managing director of disaster specialist EBI Engineering, said that London Underground also needed to carry out an urgent survey of its network of tunnels to assess their structural integrity.

He said: “The first thing that needs to happen once the police and forensics teams have finished in the tunnels is to see what damage has been done.

Esper, who has worked on structural risk assessments in the wake of disasters such as the 1995 Kobe earthquake in Japan, added: “It could take between two and four weeks to properly examine the full extent of the damage.

“Once this has happened it’ll be possible to say how long repairs might take – perhaps two to four weeks again.

The first thing that needs to happen is to see what damage has been done

Philip Esper, managing director, EBI Engineering

“If the main structures of the tunnels aren’t that badly damaged it shouldn’t take that long to get trains up and running again, but after the first three to four days is when we’ll have a better idea,” he added.

When Esper spoke to QS News last Friday he had already been contacted by Trans4M – one of three divisions of the Metronet consortium that is led by Atkins which has a contract to upgrade and maintain six underground lines including the Circle Line which was damaged at Edgeware Road and Aldgate stations.

The areas that Esper said London Underground could improve to tackle future attacks included:

• Installing bomb detectors similar to those in many new buildings at “high risk areas” of central London such as busy interchanges and lines with deep underground tunnels;
• Examining the lines and strengthening some of the older ones where they bear the greatest load – such as where they pass beneath large buildings or are under pressure from water;
• Safe havens in tunnels – in the event of an evacuation from a train which is stuck in a tunnel there should be safe areas where passengers can gather and then be led to the nearest exit as opposed to gathering on the track where there is a risk of electrocution or of tunnel collapse.

Esper said that he knew such measures would add millions to the contracts of the consortia carrying out upgrading work to the London Underground, but added: “Yes these would cost a lot but compared to the cost of people’s lives it has to be worth it. There could be much bigger bombs that would cause a tunnel collapse next time.”