Crown Bridges

The Crown Bridges (Finnish: Kruunusillat) is the name given to three planned bridges in the Finnish city of Helsinki, creating a new tram link and cycle path to the island of Laajasalo.

Crown Bridges Kruunusillat
Carries	Two lines of the Helsinki tram network
Locale	Helsinki, Finland
Characteristics
Design	Cable-stayed bridge
Total length	10 kilometres (6 mi)
Width	0 metres (0.0 ft)
Height	140 metres (459 ft)
Longest span	0 metres (0 ft)
Clearance below	0 metres (0 ft)
History
Construction start	2021
Construction end	2026

Background

The city council of Helsinki decided on 31 August 2016 to build a tramway to the island of Laajasalo,[1] located to the east of Helsinki city centre. The route will include three new bridges, the longest of which will be the longest in Finland at 1.2 kilometres (0.75 mi), and its pylons one of the tallest structures in Helsinki. The bridges will have bicycle and pedestrian lanes in addition to the tramway, but no lanes for private cars. The total length of new double track, including tramways on Laajasalo itself, is about 10 kilometres (6.2 mi).[2]

There are several new areas of housing under construction on the island as of 2016. The site of a former oil shipping terminal at Kruunuvuorenranta is expected to house 12,500 new residents when construction is completed by 2025, and densification of other areas on Laajasalo is expected to add another 10,000.[2] The tramway connection over a series of bridges was originally chosen as the basis for development by Helsinki city council on 12 November 2008.[3][4][5] The discarded alternatives were an extension of the Helsinki Metro in a tunnel or over a bridge.[6][7] The completed tramway plan and its funding were finally approved by the council only in August 2016, almost eight years later.[1]

Planned tram lines following the completion of the Crown Bridges project

The island will be linked to the Helsinki city centre by a tram connection built on bridges from Merihaka via Sompasaari and Korkeasaari across the Kruunuvuorenselkä sea area and into Kruunuvuorenranta. Instead of three lines in earlier versions,[3] the approved plan includes two lines in the first stage:[2]

• Central Railway Station – Hakaniemi – Kruunuvuorenranta – Yliskylä (45-meter bidirectional tram units), and
• Kolmikulma – Central Railway Station – Hakaniemi – Kruunuvuorenranta – Haakoninlahti (existing-type rolling stock, 30-meter unidirectional units)

In the plan dated in May 2016, the bridge and tramway structures are projected to cost 259 million euros. Additionally, the required investments in a depot and rolling stock are projected at 20–25 and 75–80 million euros, respectively.[2] The stated aim is to have the tramway fully operational at the end of 2025. The total length of new double track is about 10 kilometres (6.2 mi).[2]

In 2008, the city council approved a motion that in the further planning of the Laajasalo area tram, expanding the tram network to the Herttoniemi metro station should be investigated.[5] Additionally, in case that the military base in Santahamina will be freed for residential construction in the future, provisions will be made for converting the tram lines into a light rail system that would extend into Santahamina in the south and travel in a tunnel from Korkeasaari to Katajanokka, linking with the planned north–south line of the Helsinki Metro.[3]

References

1. "Helsingin kaupunginvaltuusto päätti: Kruunuvuorenrantaan rakennetaan Suomen pisin siltayhteys" (in Finnish). Helsingin Sanomat. Retrieved 2016-08-31.
2. "Kruunusillat, hankesuunnitelma" (PDF) (in Finnish). City of Helsinki. Archived from the original (PDF) on 2016-09-11. Retrieved 2016-08-31.
3. Helsingin kaupunki: Kaupunkisuunnitteluvirasto
4. Joukkoliikennelautakunta
5. Helsingin kaupunginvaltuusto
6. Finnish Tramway Society
7. Antero Alku