Currently 20% (610 m) of the excavation towards the north is completed. This is the face that ultimately will breakthrough into the existing Skullerud water treatment plant. The project is now in the phase where systematic injections are being executed to protect the tunnel from taking in polluted water from an old garbage disposal site. This work is expected to continue for at least another 800 meters.

The 520 meter long excavation towards the south is 90% completed. Due to unforeseen geological circumstances in the southern pre-cut. The tunnel works here will have to be stopped in June until the pre-cut can be executed.


At the end of 2019 it was discovered that the portal the client had planned in Enebakkveien did not have enough rock overburden to be safely excavated. New ground investigations were carried out and the the client chose to redesign the water pipe in the portal area. The design team from Marti, is currently finishing the new design for the pre-cut which will be executed at the end of summer 2020.


The main tunnel will break through into an existing facility. The works on the pre-cut are expected to take place directly after the southern pre-cut is completed. This will include very careful blasting since we are working in close proximity to the existing water treatment plant.

Marti Tunnel AG
Seedorffeldstrasse 21
CH-3302 Moosseedorf
+41 31 388 75 10