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Norway's Deepest Tunnel: An Engineering Marvel Under the Sea
2 Dec
Summary
- Norway is building the world's longest and deepest undersea road tunnel.
- The Rogfast tunnel will reduce travel time by 40 minutes between key cities.
- Construction faces challenges with saltwater leaks and precise engineering.

Norway is pushing the boundaries of engineering with the construction of the Rogfast tunnel, set to become the world's longest and deepest undersea road tunnel. This 27-kilometer (17-mile) project, planned for completion by 2033 at an estimated cost of 25 billion Norwegian kroner ($2.4 billion), will dramatically enhance travel along the nation's western coast. It is a key component of the E39 highway revamp, aiming to create a ferry-free route.
The Rogfast tunnel will reach a staggering 392 meters (1,286 feet) below sea level, presenting significant technological hurdles. Challenges include managing saltwater leaks and achieving a construction precision of just 5 centimeters (1.97 inches) as two teams meet in the middle. Advanced laser scanning technology is employed to create a digital twin for accuracy, crucial for saving time, resources, and reducing waste.
Beyond its depth and length, Rogfast introduces innovative features like a deep-sea roundabout connecting to the island of Kvitsøy. The tunnel will also incorporate a high-tech longitudinal ventilation system and real-time incident alerts to ensure motorist safety. The project is expected to boost regional development, improve access to services, and positively impact local economies.



