Big day for connecting up tunnels: breakthroughs on four sites

On 7 September, the tunnels between a total of four construction sites will be connected on the west metro’s Matinkylä–Kivenlahti stretch. In the various contracts for the west metro, several tunnels are being excavated simultaneously and will eventually meet at the contract area boundary. The stone wall between the tunnels is 3–6 metres thick on average, and this wall will be removed during the breakthrough.

The last remaining thin rock plug separating the tunnels excavated between Kaitaa and Soukka will be blasted through on Thursday afternoon, and the breakthrough between the Sammalvuori depot and the Espoonlahti construction site will take place in the evening. The breakthrough between Sammalvuori and Espoonlahti will occur in phases: first, a narrower connection will be opened between the tunnels and then the hole will be enlarged. The breakthrough between Soukka and Kaitaa will be accomplished with a one-off blasting operation.

The first breakthrough for the second phase of the west metro was made on 10 August, between Kaitaa and Finnoo. This new breakthrough will open tunnel connections from the Kaitaa construction site to both of the surrounding tunnels.

Excavations on the west metro’s Matinkylä–Kivenlahti stretch are now 90% complete. The excavations will be followed by a construction phase that has already begun for Sammalvuori.

Further information: Länsimetro feedback phone number (Mon–Fri 9:00–15:00): +358 50 377 3700