Environmental construction emphasises biodiversity
How is the Crown Bridges project progressing in Helsinki? Will the construction work cause any vibration? Is it a must to start working very early in the morning? How can I drive to Southern Helsinki? The Crown Bridges project raises questions and those questions are answered here as best as possible.
During the online event of the Crown Bridges project in December 2020, residents had the opportunity to ask questions about the project. This is a summary of the most interesting questions and answers.
1. How does decision-making related to the Crown Bridges project progress in practice? What ‘official’ decisions does the City still need to make regarding the implementation of the project? I understand that the alliance is now in the so-called development stage, which will be followed by the implementation stage. When will the decision be taken to move to the implementation stage?
The Crown Bridges project is carried out as a combination of two contracting models: The two bridges between Kalasatama and Kruunuvuorenranta as well as the construction in the land areas in Korkeasaari will be realised as an overall contract. The rest of the construction of the connection will be carried out by an alliance. The Crown Bridges alliance is now in the development stage. During the development stage, tramway plans that are more detailed than the 2016 project plan are prepared and the construction schedule and costs are defined. As a result of the development stage of the alliance, the so-called target cost is defined. Target cost means the total cost of the project, within which all parties of the alliance commit to when implementing the project. The price of the offer that won the tender for the bridge contract will be known in spring 2021. At the same time, the alliance target cost for tramway construction will be ready. It is only then that a clear idea of the cost estimate of the whole project can be obtained. If the target cost of the alliance, the bridge contract offer and other costs of the client exceed the cost estimate of the project approved by the City Council, the decision on the implementation or scope of the project will be resubmitted to the Council. If this happens, the Council’s decision will be announced in autumn 2021. Before that, the alliance will not build anything on the Crown Bridges tramway, but the alliance will start the so-called related projects (projects that the City would, in any case, be implementing along the tram route).
2. Is the financing of the Crown Bridges tram project secured (even though we are living in these so-called hard times)?
At least for now, it looks like it is secured.
3. How many people will the whole project employ until 2026 in total?
Unfortunately, we are not yet able to answer this while construction resourcing is in progress. Currently, the alliance employs about 200 people in different roles.
4. Could you tell more about the schedule of the Crown Bridges project?
In the spring 2021, we will begin the light rail project with external works in Hakaniemi and Kruunuvuorenranta at the western end of Koirasaarentie. In the autumn, we aim to begin dredging work around Korkeasaari island and preparations for the construction of the Finke Bridge and Crown Bridges.
In 2022, construction in Kruunuvuorenranta will expand to Haakoninlahti and, elsewhere in Laajasalo, to the eastern end of Koirasaarentie and to Laajasalontie. (However, before the Crown Bridges site, Laajasalontie will get another construction site.)
Construction of the new Hakaniemi Bridge will begin in Hakaniemi.In 2023, construction will also begin at the ends of the line, i.e. around the Railway Station and on Reposalmentie, Ilomäentie and Ollinraitio in Laajasalo. Construction of the Merihaka Bridge will begin in 2023–2024.
In 2024, construction will start in Nihti. In 2025, construction will start on Siltasaarenkatu.The goal is to have the connection completed at the end of 2026, and to have passenger traffic operating on the tramway in 2027.
This is the current schedule, which has been compiled to the best of our knowledge. Changes are possible.
5. How will you fill the new shoreline? Is the transport done by trucks or barges?
Both trucks and barges, depending on the landmasses available. As much work as possible is done with barges.
6. How many piles are needed and are they all impact piles?
We do not yet know the exact number of piles. At the moment, however, there are plans to use bored piles in addition to impact piles.
7. Will nearby houses vibrate due to piling?
Vibration will certainly be felt during working hours in buildings as well. However, if the construction of the buildings has been done properly, the vibration will cause no discomfort or effects other than minimal vibrations. The Crown Bridges alliance commissions surveys of buildings before, during and after piling.
8. Will there be noisy construction work in the evenings? Is it obligatory to start work early in the morning? How about at weekends?
The scheduling of noisy work is determined by the noise permit. We have not yet applied for a noise permit for the project, and these times will be specified in the permit. Usually, work that causes noise is done on weekdays between 6 a.m. and 10 p.m. We avoid doing such work at weekends. Our working hours are regulated by, for example, the Working Hours Act, noise permits and other provisions. Unfortunately, when it comes to working hours, the ideal situation for everyone is never reached.
9. When driving from the north towards Southern Helsinki, is the traffic directed to Mannerheimintie and from there to Ullanlinna, for example?
During the works, Sörnäisten rantatie will have two lanes in both directions, so the current routes are mainly available. According to the traffic forecast describing the working time arrangements, some of the traffic will also shift to the mentioned route and approach the city centre via Mannerheimintie.
10. Why is Helsinki being built on fill land just as it has been done in the past?
Helsinki local master plan 2016 aims at complementary construction, especially at rail hubs. In addition to the complementary construction of the area, the fillings will also make it possible to develop the area's public spaces, parks and beach areas to be more comfortable.
Read all the questions and answers of the online event Rakentamisen vaikutukset liikkumiseen Hakaniemessä ja Siltavuorenrannassa 2021 (in Finnish).
Pictures: Crown Bridges