Customers on London Underground's (LU's) Central line are getting smoother journeys sooner thanks to the innovative use of a century-old lift-shaft that has been brought out of retirement to speed up track renewal works .
After serving the busy but now defunct Post Office Station between 1900 and the 1930s, the 114 year-old 33-metre deep lift shaft opposite St Paul's Underground station on the Central line has been out of commission apart from a brief period of military service when it housed the Central Electricity Board wartime offices.
But with St Paul's the focal point for large-scale track renewal on 14 miles of nearby Tube tunnels which will give customers smoother and quicker journeys, LU has converted the shaft to serve as a one-stop logistics hub to deliver all the materials needed deep underground.
The shaft now boasts two industrial-size lifts and conveyor belts to turn it into a fast and efficient delivery and extraction system. Two or three days of materials can be stored at the base of the shaft which is part of what were the station platforms. Then as soon as the station is shut to the public, materials are loaded via the station platforms, straight on to track trolleys which run out to work sites and bring waste and rubble back.
Not only does the hub mean fewer lorry deliveries to other central London stations, it also removes the need to load each night's materials into stations before getting down to work. That means LU's Track Delivery Unit can double the amount of improvement works it carries out in the Engineering Hours available to them between 01:00hrs and 05:00hrs each night. The hub has reduced emissions through fewer lorry journeys by more than 10 tonnes, and saved more than £500,000 in its first year - all money which is reinvested in London's transport network to improve services for customers.
LU Project Manager Ray Hallett, who led the rejuvenation of the lift shaft, said "Access for large scale renewal works on the Tube is a perennial problem - both underground and on the surface - and we're always looking for ways to minimise its impact on Londoners. I'd been looking at the shaft for some time, thinking we could put it to good use as it was one of the few that had not been built over. With the start of a big round of upgrade works in 2010 and ten of the sites being located in the St Pauls area, I saw a chance to bring it to life again."
Traditionally, the problem of engineering access to the Tube has been solved by restricting all deliveries, maintenance work and supplies to Engineering Hours - London Underground's "downtime" between 01:00hrs and 05:00hrs when the Underground stops running, stations are shut and the power to the rails is turned off.
During this four-hour break, all over the Tube network, workers carry all their own tools and supplies from trucks parked on the surface, down through stations and along the tracks to the work site. Then, before 05:00hrs when the trains start running, they have to take every single thing that's been carried down plus any waste or rubble, back out again.
It's time-consuming, expensive and frustrating and making it happen in any busy central London location is doubly difficult as the Capital's 21st century night time economy gathers pace.
Ray added: "We always try hard not to do anything that adds to traffic congestion above ground at any time of the day and restricting passenger access to stations - even late at night - is an option of last resort. "The Hub has proved very effective in many ways. One person can move two tons of supplies from the street to the track in 15 minutes whereas before that would take 27 men to do the same job. We can also reduce the average work gang numbers from 18 to 12 without compromising safety and we still expect to move around 10,000 tons in the first year of using this new system."