Farringdon Tunnel – Emergency Response Call-out

THE CUSTOMER

Pro Rail Services Ltd. is a Railway civil engineering contractor who execute maintenance contracts on Network Rail infrastructure. These call-out works took place on the Thameslink Route.

THE CHALLENGE

This was an emergency call out from Lanes Group Plc, who were working for Thames Water after a Thames Water 16 inch water main burst on Friday 23rd January. Network Rail teams initially attempted to resolve the flooding in Farringdon Tunnel over the weekend of 24th26th January, but were unable to find a workable solution.

Thames Water offered assistance to Network Rail on Tuesday 27th January via Lanes Group Plc, who engaged Pro Rail Services’ specialist response Rail Solutions team to create site access to allow: • Access to an operational railway location • Survey the location of existing track drainage layout and catchpits • Obtain Drainage Asset Plans from TfL • Set up and maintain an over pumping system to de-water the flooded tunnel • Provide constant stakeholder management to conclusion of call out

THE SOLUTION

The Pro Rail Services Ltd. response team met on site with both the Themes Water Network Engineer and the Network Rail Permanent Way Engineer to discuss the scope, access and to agree on achievable objectives for the next 48 hours.

Within 90 minutes of arriving on site we obtained the track drainage layout plan from TfL as none were available on site.

In parallel and working closely with both the Network Rail Permanent Way Team and the Signaller, access was obtained to facilitate the laying of hoses and the placing of pumps in the catchpits, with the outfall point identified from the TfL plans.

Teams were set up on 12 hours shifts with monitoring systems implemented so that tunnel flooding reduction could be assessed by the Pro Rail Services Ltd. Engineer, who, in turn, communicated progress to both stakeholders.

THE IMPLEMENTATION

The pumping solution – using pumps, hoses, generators, Jet-Vac tankers and CCTV equipment – took 4×12 hour shifts to de-water the flooded tunnel.

The team consisted of a competent drainage engineer, COSS, lookouts, and four skilled drainage operatives fully trained for rapid response scenarios.

It was estimated that circa 500,000 litres of water had been removed from the tunnel in this period.

THE RESULTS

Circa 500,000 litres of water removed from the flooded tunnel

Teams worked round the clock on 12 hour shifts to safely achieve the objectives

High profile event closely managed to advise all stakeholders on emergency response progress

§ “Lost” outfall and trash screen located and cleaned to allow the free flow of water

§ Potential risk to passenger services from track flooding greatly reduced by removing long term blockages and identifying where the outfall was