Rantaväylä tunnel removes a bottleneck
The construction of the Rantaväylä tunnel in Tampere, Finland, improves the flow and safety of traffic and contributes to the development of Tampere city centre. It frees up plots by lake Näsijärvi, enabling the construction of the Ranta-Tampella residential area for approximately 3,600 residents.
In the project the Rantaväylä section between Santalahti and Naistenlahti has been removed into a 2.3-kilometre road tunnel, the longest in Finland, that also goes under the Tammerkoski rapids. In addition to the tunnel, the project involves two graded interchanges and related road arrangements in the area. The project improves a 4.2-kilometre section of Highway 12.
In an alliance, cooperation is power
The Rantaväylä tunnel project has been carried out through an alliance formed by Lemminkäinen, the City of Tampere, the Finnish Transport Agency, the engineering office Saanio & Riekkola Oy, and A-Insinöörit Suunnittelu Oy. The alliance is a pioneering implementation model in Finland. In it the customer and the service providers design and implement the project together, as a joint organisation. Everyone wins when benefits and risks are being shared.
Through jointly created innovations, we were able to reduce the disruption caused by the construction site, create cost savings and accelerate the progress of the project. One of the innovations of the alliance was to change the planned location of the access tunnel.
“We built an access tunnel in the middle of the site using the existing access tunnel of the Näsinkallio sports facility. Starting from the middle, we are excavating two road tunnels east and two road tunnels west. Without this innovation, we would have needed to start excavation in the middle of the existing Rantaväylä road and to build a detour for current traffic close to the shore of lake Näsijärvi,” says Lemminkäinen's Esko Mulari, Project Manager of the Rantaväylä tunnel Alliance.
The Rantaväylä tunnel project was divided into two separate phases. The project’s development phase took place in 2012–2013 and the implementation phase began in October 2013. The tunnel was opened to traffic in November 2016, six months ahead of its schedule and keeping it's budget.