Last update 19.12.2014

Construction

Construction work on the Ruoholahti–Matinkylä section of the west metro is under way. Work on the Matinkylä–Kivenlahti section started at the end of 2014.

You can find current information on the construction of the metro in your area under Worksites at the top bar.

You can follow the construction of the west metro in the online follow-up service
In the follow-up service of the west metro, you can see the location of the rail line, the progress of the construction, and the locations of the stations and exit shafts.



Frequently asked questions and answers related to the construction

We received a notification that our home will be inspected. What does it mean? Why is an inspection necessary?
During an inspection, an inspector authorised by Länsimetro visit flats together with a representative of a property management company/maintenance company, and the objective is to survey the structure and condition of properties and document any findings. In addition, any sensitive equipment is protected. Among the most common sensitive equipment in home use are desktop computers with hard disks. Portable computers, video projectors or set-top boxes, on the other hand, do not require separate protection. It may not be possible to protect all sensitive equipment during the initial inspection. In this case, either a further visit will be arranged or the inspector will provide the resident or the office staff with special protectors that are easy to install under the equipment. Once the construction project is complete, a final survey will be performed and any damage recorded.

At what time will there be blasts?
Work that causes noise is carried out only on weekdays (Monday–Friday) at the following times:
- Tunnel excavation: Monday–Friday at 7 a.m.–6 p.m. (quiet work also between 6 p.m.–7 a.m.)
- Blasts in the tunnel: Monday–Friday at 7 a.m.–10 p.m. and Saturday at 9 a.m.–6 p.m.

A more detailed schedule will be notified to residents before work starts at each worksite. Information on each area is also available on our website under Worksites.

Does the construction of the metro cause a great deal of noise underneath our house? Will the blasts affect the foundation of our house and could there be cracks or trembling? The tunnel will be located directly underneath our house. Our house is old and built on top of bedrock.

The construction of the metro tunnel does cause some noise. The objective is to schedule the work and scale the work techniques so that there will be no unreasonable inconvenience to residents. Work techniques are selected so that there will be no damage to existing buildings. Before work is started, the condition of buildings will be inventoried. However, if there is any damage to buildings, the builder is responsible for the repairs.

I noticed that a shaft will be built near our home. What does it mean?
In the metro tunnel there is a shaft, reaching up to the surface every 600 metres, for emergency exit, smoke extraction, pressure equalisation and ventilation. There is an emergency exit stairway with fire compartments in the middle of each shaft. There will be a total of 23 vertical shafts along the whole line. The exits of the vertical shafts are in streets or public parks. The shape, structure and facade materials of the shaft buildings will be designed to be appropriate for their surroundings.

Are the clouds of steam and dust that appear at the mouth of the tunnel after blasts harmful to the environment?
Steam from the tunnel is often mistaken for dust or smoke. However, blasts create only a small amount of dust, as blasts are carried out below the groundwater level, and water is used for rinsing the drill holes. Therefore, most of the exit gas is actually water. In connection with a blast, there is an increase in the inner temperature of the tunnel, so water turns to steam when it exits the tunnel. After a blast, the tunnel is ventilated for about an hour for occupational safety reasons, as there are harmful concentrations of nitric oxide and carbon monoxide in the confined tunnel as a result of the burnt explosive materials. The purpose of ventilation is to ensure that the air in the tunnel is safe for working. During ventilation, any harmful concentrations reduce quickly, as they mix with a greater air mass.

Is it possible to hear or feel the metro traffic in operation in a building that is directly on top of the metro tunnel?
The frame noise from rail structures is reduced by attenuation, and the attenuation of steep curves is further enhanced by acoustic structures on the ceiling and the walls. Also, there is very little trembling during operation. The rails are joined together by welding, and they are placed on a bed of macadam, so the metro trains run extremely smoothly.