Metro extension, Helsinki capital region, Finland

West Metro extension, Helsinki capital region, Finland

Helsinki, Finland

Project facts

Client: Länsimetro Oy

Services: Rock and structural engineering, Architectural design, Geotechnical engineering, HVAC and electrical engineering

Project Period: 2000 - 2020

Pöyry has been involved in the West Metro project since the beginning of 2000s. Pöyry experts have conducted feasibility studies, preliminary designs as well as environmental impact assessments.

The length of the West Metro line will be 21 km in total. It consists of two parallel underground railway tunnels and altogether 13 new stations. In addition to the stations, 23 technical shafts will be built for ventilation, pressure balancing and smoke extraction. These shafts will also serve as emergency exits.

Phase 1 from Ruoholahti to Matinkylä

In the first phase, metro line with 8 new stations were built from Ruoholahti to Matinkylä. Pöyry was responsible for rock engineering at Otaniemi and Niittykumpu underground stations and twin tunnel of 3.5 km, as well as architectural, rock, structural and geotechnical engineering of access tunnels in Otaniemi, Keilaniemi and Niittykumpu. We also took care of HVAC and electrical engineering of the complete 14 km tunnel and all access tunnels.

The construction works began in Ruoholahti on November 2009. The first phase of West Metro was opened in November 2017.

Phase 2 from Matinkylä to Kivenlahti

In the second phase, the West Metro line will continue from Matinkylä to Kivenlahti. The line is approximately 7 km long and comprises five new underground stations and an underground metro depot in Sammalvuori. Pöyry is principal designer for structural, rock and geotechnical engineering for the whole second phase. In addition, we will provide rail engineering and architectural design services for the project. We are also responsible for rock and geotechnical engineering for Kaitaa and Soukka stations, and structural engineering for Espoonlahti and Kivenlahti stations.

Excavation work started in 2015. Construction works in the stations have started in phases during 2018.