Transport for London collected this year’s National Rail Awards Major Project of the Year for “the most complex and technically challenging” project ever delivered on the London Underground. Richard Wilcock reports.
Upgrading railway stations can be complex and long processes. This is even more true of a station that sits at the epicentre of one of the busiest rail networks in the world.
But the success of the Bank Station Capacity Upgrade over the course of a decade shows that collaboration, patience and perseverance is alive and well in the industry.
This was one of the reasons why the judges at RAIL’s National Rail Awards 2024 chose Transport for London’s entry as the winner of the Major Project of the Year award.
The team at TfL started this journey in 2013, with the aim of tackling the station’s ‘rabbit warren’ system of partially connected and standalone tunnels.
Passenger flow modelling and data had shown that many passengers were avoiding the station because of the arduous and complicated journeys between lines (Bank station sits at the intersection of the start of the Docklands Light Railway, and London Underground’s Northern, Circle, District, Waterloo and City, and Central lines), with crowded passageways and concourses a regular occurrence. Bank station at that time served just over 450,000 passengers per day.
For TfL, expanding the station to improve capacity was complicated. It soon became apparent that the team was limited to working with the space it had. But, as ever with stations built in a bygone era, doing so was fraught with difficulty and potentially expensive.
To ensure that project costs didn’t balloon, TfL went out to market with requirements and the project business case, rather than a concept design and a request to price against it.
It also asked its tier one contractors to design a scheme that maximised the benefits of upgrading capacity, as well as mitigating any of the risks identified in earlier design stages. It meant that contractors and the wider TfL team were working with what was already there from the outset.
However, this didn’t mean that it couldn’t maximise every inch of potential to improve capacity. The approach resulted in a widened Central Line interchange with moving walkways, triple escalator banks, and a widened concourse at the entry and exits.
Passenger flows and capacity formed a key part of the improvements, but this also meant that the team needed to improve the capacity on the running tunnels. This resulted in nearly 1,000 metres of new tunnels being built, including the new 570-metre southbound tunnel on the Northern Line.
The station’s central London location was also an issue that the team needed to consider. All this construction work was completed while working around the 31 listed buildings either directly above or neighbouring the build site. It added a complexity rarely seen in other projects.
The actual construction process over that period of time was also impressive. On the Arthur Street side of the station, the team introduced a second worksite which at its deepest was 18 metres deep and used more than 35 tonnes of steel.
Utilising a gantry crane, all waste, spoil, plant, materials and equipment were moved in and out of the central shaft. It also doubled up as a key site access point for workers.
The shaft was used to remove more than 200,000 tonnes of material and to bring to site a number of escalator sections. These were then moved with precision to their respective locations and reconstructed.
The shaft proved a pivotal part of the process, enabling the project could be completed earlier while keeping the station fully operational.
Of course, TfL also had to tackle disruption. It is an inevitable part of a project of this scale.
Bank station’s intersectional nature meant that logistically, some lines and some parts of the station were going to be affected for long periods of time, almost all the time.
To minimise this as much as possible, TfL and its main contractor Dragados decided that a 17-week closure of part of the Northern Line was the most viable way to ensure that it could complete the works required.
This closure took two years to plan. It was, after all, one of the largest and most complex closures ever undertaken on the Underground. But the two years of planning ultimately paid off, as it resulted in this part of the project working on time and to budget - in fact, the Northern Line opened one day earlier than planned.
But the real story was that these 17 weeks was the only time the station was closed during the ten-year lifetime of the station upgrade.
Ultimately, any project is measured on how well it corrected or improved on what was there before. For the Bank Station Capacity Upgrade, the NRA judges for this year’s award credited the team with “vastly improving passenger experience”.
From design to build, the passengers remained at the forefront of the planners’ minds. This was evident in the new Northern platform, which has been converted into a spacious concourse with access further improved by a new station entrance, 12 new escalators, and two moving walkways.
It could also be seen in the step-free access which has been improved for the Docklands Light Railway and provided for the first time to the Northern Line.
Understanding how passengers use the station - and how ultimately TfL would like them to use it - meant that some lines needed to be connected.
The team connected the Northern and Central lines as well as connecting the DLR with the Northern Line, ensuring that passengers could easily pass between the two lines.
A walkway and escalators opened in 2022 and has shaved nearly ten minutes off a passenger’s interchange between the two lines. A new ticket hall at the Cannon Street entrance also improved the passenger experience, making it quicker and easier to travel through the station.
One of the final pieces of this complex puzzle was the construction of a new entrance on Walbrook Street, located at the south of the station.
This entrance included two new lifts and quicker access to the Waterloo and City Line.
Overall, the successful delivery of the project has resulted in a 40% capacity increase and a reduction in interchange times by up to nine minutes.
At its peak construction, 550 workers per day worked on the project. And over its lifetime, nearly 40 apprenticeships were completed.
The NRA judges credited the “lengthy planning, stakeholder engagement and collaborative negotiations” with the supply chain for mitigating challenges posed by the Coronavirus pandemic and increased commodity prices and availability.
They added: “This is the first major project that was not impacted by these circumstances due to forward planning. Some of the lessons learned are now implanted in TfL’s ongoing upgrade project at Elephant & Castle.
“All in all, this is an extremely successful major project, in an extremely challenging circumstances at an extremely challenging location.”
The judges said they were impressed by what TfL described as “the most complex and technically challenging” project ever delivered on the London Underground network.
When the station’s final stage was opened in November 2023, London Mayor Sadiq Khan proclaimed the station as “world-class” and “hugely important for the City’s growth”.
Ten years in any lifetime is a long time. But meticulous planning and a shared vision has ensured that this station is fit for another 50 years.
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