Going underground Martin Pawley looks at the significance and history of London's underground, while Roland Paoletti, the client for the Jubilee Line, describes how the newest crop of stations came in
Westminster station lies below Michael Hopkins and Partners' new parliamentary building, Portcullis House, and links the existing District and Circle Line with the jle. The project involved the re-building of the station around existing services; it includes new District and Circle Line platforms as well as the new ticket hall. The massive underground structure had to be designed to restrain the forces of the earth around the large open station spaces and provide foundations for Portcullis House, above. New jle tunnels are stacked vertically where they pass the station box, to reduce settlement effects on Big Ben and Westminster Bridge. The structure is in concrete with a reflective, sand-blasted finish. Escalators are clad in highly finished perforated panels to improve acoustics. Access at ground level is via new and refurbished subways.
Described by Jonathan Glancey as 'handsome arrangements of grand passageways and undercrofts', Waterloo and London Bridge were both undertaken by the jle's own team (working jointly with Weston Williamson at London Bridge). At Waterloo, the new jle station ticket hall is sited to the north-east of the mainline station in the Colonnades, which was previously the site of the bus stand. The station itself is designed to cope with 15,400 passengers in the peak morning rush hour, the majority of whom will interchange from the overground commuter trains. The Jubilee Line is linked to the other lines by travelator.
Southwark is a legible space, designed by MacCormac Jamieson Prichard as an enjoyable place to begin or end a journey. The principle behind the spatially diverse areas is to respect and respond to the civil-engineering envelope developed in collaboration with the engineers. The progress of the passenger from surface to platform in an easy and clear fashion is paramount and the spaces through which the public move are enhanced by carefully selected materials and finishes. The naturally lit intermediate concourse is dominated by a 'cone' wall designed with the artist Alexander Beleschenko and yrm Anthony Hunt. It is 40m long and 16m high, consisting of 630 triangular panes of blue enamel glass held on stainless-steel spiders designed to withstand the wind forces generated by the trains in the tunnels.
London Bridge, designed by the jle and Weston Williamson, is constructed beneath the existing bus station at the front of the mainline station, and is used by an estimated 17,000 passengers in the peak morning rush hour. A major part of the work was not directly connected with the jle but saw the Northern Line station completely upgraded to create a new platform tunnel and concourse in line with the recommendations of the King's Cross fire inquiry. This work included a new ticket hall at Borough High Street.
Weston Williamson's brief was to expose the civil engineering wherever practical in order to reveal the station's workings to the public. The simplicity of the architecture eliminates the need for elaborate graphics and sophisticated signage. Tunnels have a purpose-designed cast-iron cladding system which offers protection from vandalism and dirt, while lighting, telecommunications and safety systems are incorporated in an overhead boom which provides a modern counterpoint to the Victorian vaulted chambers.
Bermondsey station by Ian Ritchie Architects is an engineering hybrid combining the virtues of bored tunnels and a cut-and-cover box to reconcile the depth of the station, surface restrictions and plant requirements. At street level the roof emerges with a gentle curve rising towards Jamaica Road, making a visible link to the invisible structure below. The perimeter of the building is predominantly transparent glazing which, combined with surrounding residences, will provide additional security for passengers. Concrete finishes achieve a balance of economy and elegance: ground granulated blast furnace slag (ggbs) produces a pale warm -grey concrete and the 'blade' walls to the escalator void incorporate sand aggregates designed to enhance the surface finish, lightness of colour and light reflectance. The station design provides for future development above the ticket hall and administrative accommodation on Jamaica Road.
Canada Water, by the jle team and Herron Associates, was the first of the new stations on the line to be constructed inside the London Docklands Development Corporation's enterprise zone. Built as part of the Surrey Quays redevelopment plan, it is expected to be used by 6700 passengers in the peak morning rush hour and service 10,000 local residents and 6000 workers. A connection with the East London Line and a new bus station above link the station with the rest of London's transport system.
Canary Wharf, by Foster and Partners, station has the largest passenger capacity of all the jle stations: it is as long as Canary Wharf Tower is tall. It is entirely underground, built within the drained West India Dock, using cut-and-cover construction. A new park covers the station at ground level where the only visible station elements are the three dramatic curved steel and glass entrance canopies. The volume of anticipated traffic, as Canary Wharf continues to develop, defined the guiding design principles: clarity of circulation, durability of materials and ease of maintenance. Twenty banks of escalators carry passengers to and from platforms; ticket machines etc are ranged along the sides of the ticket hall, maximising the central space. Reinforced-concrete columns stretch from platform level to the roof where elliptical bearings allow the station to move in response to geological pressures. They were cast on site and have a natural finish; the bases of the columns are clad in stainless steel to prevent damage. At platform level, concrete diaphragm walls that were cast into the ground have been left exposed.
Alsop & Lyall's North Greenwich is the station for the Millennium Dome, the largest of all the jle stations and certain to be one of the most heavily trafficked during 2000: around 7000 passengers an hour are expected to use the station. Located at the tip of the Greenwich peninsula, it is virtually invisible from ground level, apart from its entrances and ventilation shafts. It is one of the more spectacular and uplifting of the spectacles on offer to visitors who make the trip to North Greenwich.
At an early stage, John McAslan & Partners suggested modifications to the proposed dlr track alignments to ensure that the new dlr and jle platforms at Canning Town could be symmetrically located one above the other and accessed from a concourse and ticketing area below ground. The station also connects with the North London Line, London Transport buses and London City Airport buses. The in-situ concrete structure of the main entrance hall, subway, ticket hall and concourse is clad with grey aluminium panels set above a precast-concrete kerb. Ticket hall and concourse are daylit by two rooflights constructed of glass sheets suspended from a spine beam with cast stainless-steel outriggers. Two rows of precast concrete Y struts on the jle platform support a post-tensioned dlr platform structure made of precast sections; glued segmental construction allowed the structure to be assembled without the use of cranes. Platform canopies and roof structures have been designed to provide a family of aerofoils which ties the various elements of a complex interchange together.
The new station by van Heyningen & Haward lies between two other new stations, Stratford and Canning Town. It is primarily an interchange station enabling passengers to move between the District Line, the North London Line and the new jle connection. There are five principal parts: a refurbished existing ticket hall, a new ticket hall linked to the old one, the bridge link (spanning four rail lines and a busy main road), refurbishment of the existing North London Line platform and the new JL platform and upper-level concourse. The new ticket hall takes on the role of the public face of the new station, creating a welcome arcaded entrance and addressing a small, formally planted and paved square opposite the shops on Memorial Avenue. The overall composition and choice of bricks as the primary facing material is a response to the residential character of the buildings opposite the station. The overall design is based on a 6mx6m structural and servicing bay matrix which provides a consistent yet flexible design language. The extensive use of glass blocks is particularly important in the perception of the station at night.
Stratford is the eastern terminus to the Jubilee Line Extension. Wilkinson Eyre's rectangular streamlined 'shed' has been placed parallel to the Central Line embankment to the rear and looking out towards another building by the same architect, the Stratford bus station. The North London Line cuts through the new station between the east and west concourses and passes under the underground lines. Despite the complexity of this station, it is easy for passengers to find their way around, thanks to well-organised signage. The curved canopy roof is designed to produce a comfortable environment for waiting passengers, whatever the weather.