Suomenlinna sea fortress is visited by more than 930,000 people a year and the district is also home to about 800 year-round residents. The subsea tunnel connects Suomenlinna to Helsinki’s municipal services, providing residents with district heating, plumbing, water, electricity and data communication connections. Emergency vehicles can also use the tunnel.
Somenlinna’s governing body signed a contract with YIT and Pöyry, forming an alliance that will be responsible for planning and implementing the tunnel renovation project. The budget for the project is €7m.
The alliance model that is being adopted will involve the client, users, designers and contractors from the very beginning, with all parties sharing the risks and benefits related to the project.
"It is challenging to implement this project with the alliance model, especially due to its small scale,” said Ari Bergström, vice president of rock construction at YIT. “So far, the model has been primarily applied to large and complex projects, but with Suomenlinna, we get to test what we have learned in a project of an entirely different size. In addition, the unique environment also poses challenges for the implementation of the project. We are very grateful for this opportunity of both implementing the Suomenlinna tunnel project and developing our project models."
The development stage of the project, which is estimated to last until the end of this year, with renovation of the tunnel beginning in the spring of 2017.