Årsta Bridge

Årsta Bridge marks an historic moment in the expansion and modernisation of Sweden's rail network. The elegant bridge sweeps across the lush Årstaviken Bay, its rhythmic contours interacting with the existing 1929 bridge. The discreet design of the bridge does not attempt to challenge the original bridge; rather it is intended to work in harmony with it, and complement it. The organic wave form is a sensitive response to the surrounding landscape and the vibrant red pigment of the concrete resonates with the 'Falu-red' timber used in Stockholm's traditional buildings. At 833 m long, the bridge supplements the existing bridge, dramatically increasing capacity with minimal impact on the surrounding landscape. It symbolises Sweden's respect for the environment in its commitment to rail transportation - an environmentally friendly way to travel & and the sensitive insertion of new infrastructure within the beautiful waterside setting.

Following an international competition in 1994, Foster and Partners, together with Ove Arup, were selected to design the new Årsta Bridge, which incorporates two new train tracks, a pedestrian and cycle way, and a maintenance access road. On plan, the bridge incorporates a curve, and the rounded soffit responds to the sequence of bending forces as the bridge deck sweeps over the ten pier supports, which are elliptical in section. This calming geometry is a response to the tranquillity of the Årstaviken bay, and the bridge appears to recede into the setting.

Referencing traditional building methods, the formwork used to create the rounded soffit was made of solid timber planks. The result is a natural patina on the surface of the concrete, giving the bridge a textural quality, which further enhances its subtle integration with the context. The railway tracks are set down into the top of the deck section, which helps to minimise airborne train noise, as the 'trough' walls are mounted with sound absorbent steel cartridges. In addition, the rails run on cushioning to minimise vibration. The new Årsta Bridge arrives as regeneration takes place on much of the adjacent brownfield sites overlooking Årstaviken, including a new residential and commercial scheme.