Crown Bridges

Crown Bridges
Kruunusillat
Kronbroarna
The longest of the three bridges, Kruunuvuori Bridge (Kruunuvuorensilta), under construction in September 2024.
CarriesTwo lines of the Helsinki tram network, pedestrians, bikes, emergency vehicles
LocaleHelsinki, Finland
Characteristics
DesignCable-stayed bridge
Total length1,921 metres (6,302 ft)
Height140 metres (459 ft)
Longest span1,228 metres (4,029 ft)
Clearance below3.1–20 metres (10–66 ft)
History
Construction start2021
Construction end2026

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

Background

[edit]

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 bay and into Kruunuvuorenranta. Instead of three lines in earlier versions,[3] the approved plan includes only two lines:[2]

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

However, in 2021 the approved plan was split into two different stages: the tram connection will not reach the Central Station at first but Hakaniemi market square instead.[8][9] The temporary terminus serves as a hub for many public transport connections, including trams, buses and Hakaniemi metro station. The stated aim is to have the tramway operational between Yliskylä and Hakaniemi in 2027.[10] Construction of the second phase of the project will start in 2026[9] and is estimated to be completed in 2028.[11]

In the plan dated in May 2016, the bridge and tramway structures are projected to cost 259 million euros, although in 2021 the maximum price was increased to 326 million euros.[8] Additionally, the required investments in a depot and rolling stock are projected at 20–25 and 75–80 million euros, respectively.[2] The total length of new double track would be about 10 kilometres (6.2 mi).[2] In 2021 the Helsinki City Transport (HKL) ordered 23 ForCity Smart Artic X54 trams to operate on the Crown Bridges. The very same model, also known as Artic XL, is to operate on Helsinki light rail line 15 as well.

Construction

[edit]
The Kruunuvuori Bridge construction site in summer 2022. It will become the longest bridge in Finland.
Merihaansilta under construction in September 2023.

Construction of the bridges started in October 2021.[12] The first tracks were laid on Laajasalo island on 31 May 2022.[13]

Technical data

[edit]
Crown Bridges (Kruunusillat)[14][15]
Name Link Length Clearance below Construction time
Merihaka Bridge (Merihaansilta) MerihakaNihti 422 metres (1,385 ft)[16] 3.1 metres (10 ft) 2022-2026
Finke Bridge (Finkensilta) Nihti–Korkeasaari 293 metres (961 ft) 7 metres (23 ft) 2021-2025
Kruunuvuori Bridge (Kruunuvuorensilta) Korkeasaari–Kruunuvuorenranta 1,228 metres (4,029 ft) 20 metres (66 ft) 2021-2025

Further plans

[edit]

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

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  1. ^ a b "Helsingin kaupunginvaltuusto päätti: Kruunuvuorenrantaan rakennetaan Suomen pisin siltayhteys" (in Finnish). Helsingin Sanomat. Retrieved 2016-08-31.
  2. ^ a b c d e "Kruunusillat, hankesuunnitelma" (PDF) (in Finnish). City of Helsinki. Archived from the original (PDF) on 2016-09-11. Retrieved 2016-08-31.
  3. ^ a b c "Laajasalon raidevaihtoehtojen järjestelmätarkastelu 2008" (PDF) (in Finnish). Helsingin kaupunkisuunnitteluvirasto. 2008-10-02. Retrieved 2008-10-04.
  4. ^ "Päätöstiedote" (in Finnish). Joukkoliikennelautakunta. 2008-06-17. Archived from the original (DOC) on 2011-06-11. Retrieved 2008-06-30.
  5. ^ a b "Päätöstiedote nr 20" (in Finnish). Helsingin kaupunginvaltuusto. 12 November 2008. Archived from the original on 20 May 2009. Retrieved 13 November 2008.
  6. ^ "Helsinki: Current plans on developing the tram network" (in Finnish and English). Archived from the original on 2008-06-07. Retrieved 2008-06-24.
  7. ^ Alku, Antero (2008-06-27). "Helsinki: Laajasalon raitiotie". www.kaupunkiliikenne.net (in Finnish). Retrieved 2008-06-30.
  8. ^ a b "Public transport Helsinki City Council approved the price increase for Crown Bridges". pledgetimes.com. 2021-08-25. Retrieved 2021-08-27.
  9. ^ a b "The city council decided on the phasing and costs of the construction of the Crown Bridges tramway line". kruunusillat.fi. 2021-08-25. Retrieved 2021-10-31.
  10. ^ "Hanketietoa". kruunusillat.fi (in Finnish). Retrieved 2021-08-27.
  11. ^ "Suomen pisin silta ja miljoonahanke Kruunusillat etenee kustannuskiistoista huolimatta – sen raitiotie valmistuu useammassa osassa". Yle Uutiset (in Finnish). 2021-08-25. Retrieved 2021-08-27.
  12. ^ "Rakentaminen alkaa näkyä merellä". kruunusillat.fi (in Finnish). 2021-10-12. Retrieved 2021-10-16.
  13. ^ "Kruunusillat-raitiotien ensimmäiset kiskot laskettiin maahan 31.5". www.sttinfo.fi (in Finnish). STT. 2022-06-01. Retrieved 2022-06-02.
  14. ^ "Raitiotieyhteys Laajasaloon / Yleissuunnitelma" (PDF) (in Finnish, Swedish, and English). Helsinki city. 2016. Retrieved 2022-10-27.
  15. ^ "Kruunuvuori Bridge, the new icon of Helsinki" (in Finnish and English). Kruunusillat. 2021. Retrieved 2023-03-09.
  16. ^ "Merihaansilta" (in Finnish). Kruunusillat. Retrieved 2023-03-09.