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The Tube's unsung heroes

NEWS FEATURE - LUL: Nina Lovelace reports on LUL's hard pressed maintenance teams.

LONDON'S CREAKING underground system will welcome the £16bn worth of funding over the next 15 years from the government's Public-Private Partnership (PPP) scheme. Until now cash has been scarce, and London Underground (LUL) has been reduced to running a system on a hand-to-mouth basis.

LUL has kept running for the past decade because of its experience in knowing what it has - and how far it can be pushed - explains LUL chief engineer Keith Beattie.

'The system is like a piece of elastic. It's all about knowing how much you can stretch it, ' he say, as he sits in his office at LUL's St James Park headquarters.'

And years of inadequate funding have seen the elastic stretched to it limits. General system reliability has been falling because LUL has been forced to patch and mend the system as best it can, rather than solve recurring system failures by renewal and upgrade. This has been particularly true of the oldest lines, the Circle, District and Metropolitan.

LUL engineers have become emergency asset management experts by, as Beattie says, 'sweating the assets'. This means making the trains, tracks, signals, bridges and embankments work harder by extending their design lives. As a result some of the equipment is well over 100 years old.

'We've got some stuff out there that should be museum pieces, ' says Beattie.

LUL's patch and mend system is the result of the way the Tube has historically been funded with an annual goverment grant.

Faced with other spending priorities such as health and education, the Tube often fell by the wayside, says Beattie, with promised funding often withdrawn at the last minute. LUL therefore got used to scrapping its renewal work plans.

Successive governments also had difficulty deciding what was the future of transport and the investment needed. In the late 1980s and early 1990s, the answer was 'not much', with Tube journeys expected to fall rather than rise because of the trend for home working. 'But society has not worked like that, ' says Beattie.

By 1997 it became obvious that transport was a priority and longer term investment was needed. The Labour government replaced annual spending reviews with a rolling three-year funding regime, but even this was far from generous, says Beattie, as it assumed that the PPP would arrive by 2000. When it didn't, LUL was plunged back into yearly financial insecurity.

That the Tube has kept running is solely down to what Beattie describes as LUL's 'unsung heroes' - its maintenance teams.

LUL currently has three full-time emergency response maintenance units, working from strategic locations like Baker Street and Aldgate. 'They can fix just about anything, ' says Beattie, not without pride.

Much of the work they need to do is more obviously reliability based - such as signal and train failures - but as Beattie explains, reliability problems can swiftly turn into safety issues, as trains become stuck and delayed and overcrowded trains slowly overheat in tunnels.

Some of the most regular problems are with signal wiring.

'We've got copper wiring that was put in the 1950s, with a 25 to 30 year design life, ' he says. As a result some has been slowly oxidising, creating what is known as a 'green spot', causing the shortcircuiting and signal failure all too familiar to many Tube passengers.

Plastic sheathing of the wires fixes the immediate problem.

Another common call on maintenance staff is to inspect track ballast. Water ingress into the Tube tunnels causes fines in the track ballast to wash away, leaving areas of track incorrectly supported and potentially unstable. The answer is often speed restrictions, says Beattie, when really new extensive track and track and ballast replacement are needed.

Then there are always the routine inspections for broken rails, he adds: 'We do have the potential for gauge-corner cracking, ' he says, but adds that lower train weights and speeds on the Underground makes it less of an issue than for the national railways.

Rolling stock also causes problems, says Beattie, with the oldest trains on the Metropolitan and Circle line suffering from degrading suspension.

But, ironically, new trains can also cause major delays. Many, such as those phased in after the recent Central Line upgrade, have automatic self-diagnostic equipment which calls for them to be withdrawn from service when work needs to be done.

Trains went into the workshop when they needed only minor repairs and could still have run, explains Beattie.

Escalators are another major maintenance hotspot, simply because of the massive amount of wear and tear they suffer on a daily basis, says Beattie. They can cause serious overcrowding in stations when they are out of action and can also be a safety hazard if they come to a sudden halt. 'Escalators can undergo vast material stress changes throughout their 20 hour working day.'

But for every repair that is carried out, LUL receives several more letters of complaint, says Beattie. 'The public don't see the vast army of technicians out there at night, making the system right, and making sure it is safe to run the following morning.'

The three emergency teams were formed when LUL was split into three maintenance companies and one operating company, as part of 'shadow running' in preparation for the PPP, explains Beattie. The nine teams responsibile for a line each were amalgamated, which has helped the teams focus on groups of lines with similar problems.

Additional support comes from inspection staff contracted in from outside to ensure that the regimes are rigorously upheld. Some maintenance has also been handed over to the private sector. Alstom, for example, has a contract for the ongoing maintenance of the rolling stock on the Northern Line.

Beattie admits that for all of its improved management of existing assets, LUL's management of new build projects such as the Jubilee Line Extension has not been as successful. The Jubilee Line Extension ran 60% over budget and programme, and has experienced numerous problems with new signal technology.

This was far from surprising in hindsight, argues Beattie:

'Before the Jubilee Line Extension, LUL had no experience of running large new build projects. We're not like Bechtel, doing it every day.'

In the future Beattie hopes that the PPP will bring together the best of both worlds, by combining the experience, maintenance skills and system knowledge of LUL's maintenance staff with the new-build experience of the private sector.

If PPP does get the go ahead the three LUL maintenance companies will be transferred to the private companies, leaving the operating arm of LUL to merge with Transport for London.

So, says Beattie, the same man who is out there maintaining the Tube for LUL today will be the same man maintaining it for a private firm under the PPP. He will be part of the same team which has been nursing the Tube every day for the past decade, and which is desperate finally to see it get the attention it deserves.

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