London’s Green Park Station has undergone a major transformation in time for next year’s Olympic Games. Declan Lynch sees a station where improved access has been incorporating into its new design.
At the north eastern corner of Green Park sits a brand new, modest, but distinctive landmark. The upgraded Green Park station entrance has a unique street level design, sitting above a station upgrade which allows step-free access down to the platform.
The biggest change is the attractive new ramped entrance on the south side from the park into the ticket hall which is beneath Piccadilly. The park slopes uphill towards the station and engineers have run a footpath through a newly created, landscaped cutting into the station. On the south side of Piccadilly is a new canopy roof and lift entrance, allowing step free entrance from the northern entrance as part of £48M revamp.
“It’s a fantastic design,” says Tube Lines chief executive Jon Lamonte. Main contractor and project manager Tube Lines together with lead designer Capita Symonds are leading the £48M upgrade. “We’ve considered the local area, which has resulted in us using Portland stone on the entrance building.”
Below street level, Green Park station has been extended on its eastern edge to provide step-free access from the ticket hall level to the platforms. A new lift has been constructed that takes passengers from station level down 15m to the Victoria Line, and then another 10m to the Piccadilly Line. Passengers can then use an existing lift to access the Jubilee Line - the deepest level.
The remodelled station will have three new lifts and an attractive ramped entrance, together with a striking canopy roof. Work is on track for completion in December.
Converting the station to enable step free access from street level to platform was a key Olympic requirement. The station is a vital interchange for visitors to the London 2012 Games, as it connects Heathrow via the Piccadilly line to the Olympic park via the Jubilee line.
“Opening up Green Park enables so many journey opportunities,” adds Transport for London (TfL) senior planner David Leboff.
TfL’s takeover of Tube Lines last year did not affect the project according Lamonte.
“It brought us closer together with our client,” he says.
Creating step-free access in central London’s Underground stations is challenging given the space constraints. But Tubelines was able to utilise the space in neighbouring Green Park, a Royal Park for site office, tools and equipment used on the job. Through consultation with Westminster City Council, the Park authorities and local communities the team was allowed to use limited park space says TfL senior planner David Leboff.
The station upgrade began in April 2009 with Tube Lines mobilising in Green Park itself, adjacent to the station.
First task was to divert services, principally a BT telephone exchange which serves most of Westminster. By December, the team had installed an acoustic wall between the work site and the existing station to enable 24 hour working.
Using an 8t excavator, engineers then sank a 10m by 6m shaft 28m deep into the London Clay to create a lift shaft.
Congestion underground meant the engineers had to locate the lift shaft between the Victoria Line escalator barrel and the northbound running tunnel. To check that there were no adverse effects on existing structures, hydraulic jacks were placed underneath the Victoria Line escalator barrel and measurements taken every 30 minutes.
“As it turned out there was less than 5mm movement so [the jacks] weren’t needed in the end,” adds Leboff.
This 28m shaft serves the Victoria and Piccadilly lines. Once that was completed, engineers constructed a small tunnel to connect it with the platforms for both lines. Travellers requiring the deeper level Jubilee Line can reach it via an existing lift which serves the Piccadilly Line.
At street level, most visitors to the station will notice the canopy roof and redesigned pathway on Piccadilly lane.”It was very congested prior to the upgrade,” adds Leboff.
Before the upgrade, a large ventilation shaft jutted into the footpath on Piccadilly.
Engineers have remodelled the ventilation shaft into two smaller structures and created a brand new lift entrance which supports the green canopy.
The canopy’s light green colour was chosen by artist John Maine who was commissioned to help with the design. It matches the roof top of the neighbouring Ritz hotel.
Client: TfL/London Underground
Project Manager: Tube Lines
Excavation subcontractor: Joseph Gallagher Group
Lead Designer: Capita Symonds
Architect: Feilden & Mawson