The Kruunuvuorensilta’s tram line, set to be completed by early 2027, will form part of a 10-kilometer system connecting central Helsinki with Laajasalo, which is expected to double in population over the next two decades.

Construction of the $142-million Kruunuvuorensilta, designed by the team of U.K.-based Knight Architects and WSP Finland, was carried out by the joint venture of Finnish construction firms YIT and Kreate Oy. The four-year effort, which included the two-year-long concrete casting of the pylon, was itself a model of sustainability, with the use of low-emission materials and renewable energy sources. The total carbon footprint is approximately 129,000 tonnes of carbon dioxide equivalent, of which 76% originates from construction and 24% from operation and maintenance over a 50-year period. Helsinki is working toward a citywide goal to be net-zero carbon by 2040, and negative-carbon afterward.

"Bridges of this size are rarely built exclusively for public transport, pedestrians and cyclists," Knight Architects stated in a press release. 

Creating a signature bridge with a 200-year design life proved equally challenging, given Helsinki’s demanding landscape and coastal location that results in exposure to a wide range of weather conditions. The structure’s stay cables are designed to remain in constant slight motion in the wind, helping prevent ice formation. Ice accumulation is further reduced by enclosing the cables in textured plastic sheaths that cause ice to break off into fine particles. Other features include a wind warning system, with strong wind alerts displayed on light boards at both ends.

Other features include a generous, clearly organized deck providing wide, legible routes that support intuitive movement for pedestrians and cyclists; a curved alignment allowing users to see their destination ahead, reducing the “vanishing point” often found on straight bridges; and a “family” of three parapets that maintain a high-quality, consistent pedestrian experience, protect against prevailing winds and maintain views. 

The Crown Bridges program, which began construction in 2021, has also included street and utility improvements along the route, including replacement of an existing vehicular crossing in Helsinki’s city center to eliminate ramps and improve accessibility for pedestrians and cyclists.

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