Sotra tunnel achieves breakthrough

After two years, around 1,000 blasts and nearly 250,000 working hours, breakthrough has finally been achieved in the Drotningsvik Tunnel. The project is now approaching full breakthrough in all four road tunnels.

Bergen’s Mayor, Christine B. Meyer, had the honor of firing the breakthrough blast in the Drotningsvik Tunnel. At a safe distance, she pressed the button together with rock blasting supervisor Andreas Hagen Hella at 12 noon yesterday.

Project manager for the Sotra Connection, Lene Sælen Rivenes, reports that the project is now nearing full breakthrough in all four road tunnels. She is highly satisfied with ticking off breakthrough in yet another road tunnel in the PPP project.

“The breakthrough in the Drotningsvik Tunnel is extra special, since it’s the longest tunnel we’re building. After two years of demanding work through complex terrain and close to the current national road, we now have breakthrough in both tubes. This is the result of solid effort from everyone involved,” says Rivenes.

Hidden under rock pile

The actual breakthrough cannot be seen for a few more days, but the project manager assures that there is a hole through even though you can’t see it with the naked eye – yet.

“We have breakthrough, even though right now it looks like a rock pile. Here we’re so close to the viaduct out to the Sotra Bridge and the towers that the blasts are small, and the breakthrough is hidden under the rock pile to protect the tunnel outlet. In a few days when the blasted rock has been removed, we can finally see light at both ends in both tubes of the tunnel,” says Rivenes.

The most complex road tunnel

The Drotningsvik Tunnel is the longest and most complex road tunnel in the project. The tunnel runs from Storavatnet in Bergen and emerges in Drotningsvik where the national road continues out onto the New Sotra Bridge. The first blast was fired on November 2, 2023. The tunnel has two ramps for exit and entry to and from Drotningsvik. The ramps total approximately 1.2 kilometers.

Project director at Sotra Link Construction Pedro Rodriguez thanks both neighbors and road users for their patience and cooperation.

“We are proud of the efforts of the tunnel team at Sotra Link Construction, who have shown great ability to find solutions in the face of challenging ground conditions. At the same time, we want to extend great thanks to neighbors, road users and businesses in the area for their patience and good cooperation along the way,” says Rodriguez.

Extensive work remains

Now the work of fitting out the tunnel begins. Among other things, electricity, water pipes and stormwater systems must be installed, and eventually prefabricated concrete elements will be mounted along the tunnel walls. The final part of the job is installing lighting, ventilation fans, firefighting equipment and safety systems in the tunnel.

When the tunnel opens, it will be possible to set up two-way traffic in one of the tubes if an incident occurs in the other. This flexibility will contribute to better traffic flow and reduced risk of stoppage on National Road 555, which is heavily trafficked.