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A masterplan for movement around central London’s busiest station
London Bridge station is about to undergo a six-year redevelopment as part of the £6.5bn Thameslink programme to increase north-south rail capacity across London. But how will the works change the local transport network? Andrew Forster met Network Rail’s Alex Machin and Parsons Brinckerhoff’s Graham James to find out
I have a soft spot for London Bridge. The station, that is. I first set foot on it early one Friday morning in the summer of 1983 – a bleary-eyed 12-year old, having travelled with my dad on the overnight train from Edinburgh for a weekend’s trainspotting in the capital. I watched agog as train after train pulled in, disgorging thousands of commuters on their way to work in the City. I’d never seen anything like it.
This spectacle of human life continues today. During the weekday morning peak, trains in/out of London Bridge carry 140,000 passengers – more than any other central London station – though many continue on to Charing Cross or Cannon Street. In recent months commuters have witnessed the Shard – a mixed use tower and Europe’s tallest building – rise above the station. But soon they should be witnessing the redevelopment of the station itself, one of the biggest parts of Network Rail’s £6.5bn Thameslink programme to increase north-south train capacity across London.
To find out more about the project – and particularly its transport planning aspects – I’ve come to meet Network Rail’s Alex Machin, who managed the station planning application, and Graham James, a principal transport planner at consultant Parsons Brinckerhoff, who led the transport assessment work that supported the planning application (The architect for the station is Grimshaw and the lead design consultant is WSP).
London Bridge station is split into two halves: on the south side nine terminating platforms are used by Southern services running to destinations such as Brighton, Uckfield, Horsham, West Croydon, and Victoria. On the north, six through platforms are served by South Eastern services between Charing Cross or Cannon Street and destinations such as Dartford, Gravesend, Tunbridge Wells, Dover, Hayes and Orpington. These platforms are also used by First Capital Connect’s Thameslink services connecting Brighton, Sevenoaks and Sutton in the south, with Luton and Bedford in the north, via Farringdon and St Pancras International.
Such is the frequency of trains using the through platforms at London Bridge that, according to Network Rail, platform 6 is the busiest platform in Europe. Capacity, however, is already constrained – so much so that only one Thameslink train an hour can be pathed through the station during peak hours.
The track, signalling and station works will enable up to 18 Thameslink trains an hour to run in each direction through London Bridge. The number of through platforms will be increased from six to nine and the number of terminating platforms cut from nine to six. Perhaps the most eye-catching aspect of the plans is a new ground level concourse beneath the platforms.
Construction work is due to begin next year and take six years to complete. Trains will have to keep running throughout the period, though some Cannon Street and Charing Cross services will pass through without stopping during 2015 and 2016.
There’s still some uncertainty about the works because local community group the Bermondsey Village Action Group (BVAG) has launched an application for a Judicial Review of the planning permission, focusing on how the heritage impacts were considered (see page 5). The High Court will hear the application next month; were BVAG to ultimately win its case, Network Rail would have to start the planning process all over again.
Machin explains that the planning application approved by the London Borough of Southwark in March was actually the second application for the station redevelopment. Southwark originally granted planning permission in 2003 for a Railtrack-inspired redevelopment featuring an office complex above the station. Network Rail didn’t want the office block and so prepared a new application.
The new plans are ‘future proofed’ to 2076, according to Network Rail, which says they will deliver a 66% increase in passenger capacity. The big change for passengers will be the new ground level concourse underneath the platforms. Network Rail is promising it won’t be a dark and dingy place, with natural light flooding in through canopies covering the platforms.
Currently, passengers enter and exit London Bridge station at the west end, either via a concourse in front of the terminating platforms or via escalators at the entrance to the London Underground station.
“The new station will be completely different because we’re bringing the concourse down to ground level, so people at street level will come straight into the station concourse [from Tooley Street on the north side and St Thomas Street on the south side], which is going to be beneath the platforms,” explains Machin. (The concourse in front of the terminating platforms will also be retained).
As well as enhancing the environment for rail travellers, the new concourse will help improve north-south pedestrian movement between the offices and shops that front the River Thames to the north with local communities and Guy’s Hospital to the south.
Pedestrians can currently walk through one of two road tunnels under the station – Stainer Street and Weston Street – but neither offer attractive routes. “Southwark was very keen to open up the station so that the public don’t have to walk through these dark, narrow tunnels,” says Machin. The Weston Street tunnel will be permanently closed to vehicular traffic to make room for the concourse. Stainer Street, immediately adjacent to the concourse, will be converted into an attractive pedestrianised thoroughfare, providing a north-south route even when the station is closed at night.
Parsons Brinckerhoff undertook pedestrian simulation modelling using Legion software. Unusually, says Machin, the modelling extended beyond the station boundary. “We normally develop a pedestrian model for a station and it stops where the station finishes,” he explains. “But on this project the local authority were very keen to understand where people were going to go.”
Currently, thousands of commuters exit the station and walk across London Bridge into the City of London. But, by building the new concourse further east, many are expected to walk through the More London pedestrian area towards City Hall and cross Tower Bridge.
A new public space will be created outside the concourse on Tooley Street (see image). “There was a very strong public realm goal to have this as a nice open area and have a straight pedestrian desire line route across there [to More London], which, wearing my pedestrian-friendly hat, is absolutely right,” says James. “Wearing the ‘try and shoehorn the traffic engineering into the site’ hat makes it a little bit difficult because you’re trying to provide a pedestrian crossing just upstream from a junction. At one stage we thought the way to make it work would be to move the pedestrian crossing further east and then the architect said, ‘Look, we really, really want that lovely straight pedestrian crossing, can you please see what you can do to accommodate it?’ And we managed it.”
The redeveloped station isn’t expected to create problems for the London Underground, says Machin. “Transport for London was concerned about passenger flows to the Northern Line but all our figures proved it would work,” he says, adding that the increased Thameslink capacity could actually relieve the demand on the Tube line.
Where will all the traffic go?
The planning application required both a temporary traffic management plan, to cover the six-year construction period, and a permanent version. During the construction phase, part of St Thomas Street, a Red Route on the south side of the station, will be closed and used as a works site. The two one-way roads under the station – Stainer Street and Weston Street – are to be permanently closed. Weston Street serves a local traffic function but Stainer Street is more significant, being part of the Transport for London Road Network.
Parsons Brinckerhoff modelled the effects of the closures and traffic management plans using TRL’s Transyt and JCT’s LinSig software, plus Transport for London’s Central London Highway Assignment Model (CLoHAM). CLoHAM is one of five sub-regional models that TfL has developed covering all of London (LTT 25 Mar 11).
“The reason we started getting into CLoHAM was we realised there would need to be all these diversions a bit further out and you don’t do a Transyt model for a huge area,” James explains. “In the pre-CLoHAM days that would have required a really big investment – a big five-figure sum in developing a model.”
James says CLoHAM is capable of doing “80% of the job for 20% of the public money”. Network Rail had to pay TfL £10,000 for a user licence, plus some modelling time for Parsons Brinckerhoff.
“I’m glad in the end we did use CLoHAM because it gave TfL, Southwark and us a lot of reassurance,” says James. The model did have some limitations that a bespoke model would not have, he says. “With these models you’re dependent on the zoning structure and if we were building one from scratch for our area we’d have used quite tight zones representing individual streets. With CLoHAM the zones are coarser. We had an odd result in one of the scenarios [for temporary traffic arrangements] that suggested that traffic on that part of Bermondsey Street to the south of St Thomas Street would go up by about 200%.
“We looked at it and thought, ‘no that can’t be right’. We looked at the coding in CLoHAM and there was a coding error that we hadn’t spotted the first time, so we ran it again and it still showed a big increase in traffic that we thought couldn’t be right. Eventually we decided it must be down to the zoning structure – that there was a particularly coarse zone that was sending traffic up Bermondsey Street because that was the only way to get there in the model, it was just not there in reality.”
This put the consultants in a difficult situation. “We had this dilemma,” says James. “Our modelling was telling us a quite frightening figure we didn’t quite believe. Do we report it or do we say, ‘no it can’t be true, let’s apply an adjustment’? In the end I suggested to Alex, ‘Look, we’ve got to be transparent, we’ll report this and say we don’t quite believe it.’ So we put this in the report, that the model shows this increase, we don’t think it’s right.”
An objector seized on the figure when the planning application went before Southwark’s planning committee but James is satisfied he did the right thing. “I’m still glad we did it like that because no one can accuse us of fiddling the figures.”
Finding temporary arrangements for westbound traffic was fairly straightforward because there is an easily identifiable alternative route but James says managing eastbound traffic was a tougher nut to crack. One option was to sign traffic down a largely residential A road (Long Lane) to the south of the station but the London Borough of Southwark was unhappy with that idea. The final agreed solution was a longer diversion route via the Bricklayers’ Arms junction further south.
“Of course, the worry is that drivers will say, ‘Ha! I’m not bothering with that malarkey, I’ll just go the way I want to go, straight down Long Lane’,” says James. “What we eventually agreed with Southwark and TfL was that we would put in a monitoring regime and that went in the Section 106 agreement. If there was significant extra traffic on Long Lane then Network Rail would pay for remedial measures – probably some sort of traffic calming.”
It’s good to talk
James and Machin agree that the planning process was helped by Southwark’s enthusiasm for the principle of a modernised station. Machin nonetheless emphasises that there were naturally some difficult negotiations with officers. “They would want more than Network Rail wanted to give.”
James emphasises the collaborative way in which the traffic management arrangements were developed. “Network Rail was very good, they gave me the ability to talk at a technical level with [Southwark/TfL] officers, which saved an enormous amount of time and effort.” This isn’t typical, he says. “Sometimes everything has to go through the client person and you’re almost aching to get some feedback from the [council] officers.”
It was through this joint working that the puzzle of finding a permanent solution for eastbound traffic was solved. In a nutshell, the arrangements involve reversing the one-way operation of two streets to the east of the station that cross Tower Bridge Road.
“We were all scratching our heads about it,” says James. “It’s a great example of collaborative working: in the end we sat down with Southwark and TfL officers and we had a few ideas that we batted around. The idea that was eventually adopted came from Tim Gould [group manager, development control and strategic projects] at Southwark.”
Although it features in the planning application, the permanent traffic scheme may actually never be implemented. That’s because there are hopes the temporary arrangements will work so well that St Thomas Street on the south side of the station doesn’t have to be re-opened as a main road when the construction work is completed.
“The hope is that, towards the end of the construction period, looking at the traffic figures and so on, with St Thomas Street closed, traffic diverting elsewhere, there are no ill effects,” says James. “If there’s no ill effects then we may be able to say: ‘Ok, let’s not make St Thomas Street this through route, let’s re-open it as a much more local community-faced street’.
“Everyone was pretty much agreed that St Thomas Street, although it’s a Red Route, is a road that would be nice if it wasn’t,” he adds.
James believes this open-ended arrangement for the final traffic arrangements is fairly novel. “I can’t think of another example where it’s been left open-ended with a plan like that. There must be some but I haven’t found any. This is an important approach as it provides all parties with the flexibility to implement what is actually required at the time, in the light of experience and circumstances. Hopefully no one is thinking that that [the currently planned permanent scheme] is what will definitely happen. But we know we’ve got a plan that can work.”
Machin says Network Rail will contribute the same amount of funding to turn St Thomas Street into a community-focused street as it will to implement the currently proposed permanent scheme.
With the planning application approved, Parsons Brinckerhoff’s involvement in the project is over. Contractor Costain has its own traffic and transport advisers, a Hyder/WSP joint venture.
“There is a lot still to do,” says James. “Once you’ve got through your planning permission that is really demonstrating that it can be done feasibly and without too much disruption. You then get into the nitty-gritty of a construction management plan for each stage and this being a six-year project it has several stages of construction.”