Norway's plans for a $56 billion 'floating tunnel'

Norway's proposed floating tunnel. Photo / Norwegian Public Roads Administration

This is one extreme answer to the problem of the commuting and slashing travel times — but will it work?

The downside of living in a country with spectacular snow-capped mountains, fjords and glaciers is it's very difficult to get around.

The dramatic terrain in Norway, especially along the west coast, makes travelling difficult for the 5.3 million people who live in that part of the country.

Travelling the 1100km between the west coast cities of Kristiansand in the south and Trondheim in the north, for example, takes 21 hours and includes no less than seven ferries.

A rendering of the project. Photo / Norwegian Public Roads Administration

Beautiful as the land may be, that's a big nope from us.

But the Norwegian government has come up with an ambitious plan, set to cost a whopping $56 billion, to solve the problem.

And it includes underwater "floating" tunnels 30m under the surface of the water.

CNN reports the infrastructure includes bridges and the world's deepest and longest rock tunnel that will be drilled into the seabed. It will be 392m deep and 27km long.

There will also be three suspension bridges and five floating bridges supported by pontoons.

The project will link up with motorways on land so cars will be able to drive along it, eliminating the need for those slow, fjord-crossing ferries along west coast.

While the concrete tunnels are described as "floating", in reality they're held in a fixed position by cables that are anchored to the seabed or tethered to pontoons, CNN explained.

It's not a radically new concept: an idea for a floating bridge was proposed along the English Channel back in 1882, although it was vetoed.

The other advantages of the underwater transport system is it can withstand waves, makes no noise, and has minimal impact on the landscape.

It would make travelling along Norway's west coast a lot easier. Photo / Norwegian Public Roads Administration

"That would be an advantage … (for) people living in the area," said Arianna Minoretti, the chief engineer of the Norwegian Public Roads Administration overseeing the project.

The biggest risks are explosions, fire and overloading, although the infrastructure will be subjected to rigorous testing, she said.

Research by the administration, along with the Norwegian University of Science and Technology's Center for Advanced Structural Analysis, suggests explosions — say, of a truck carrying dangerous goods inside the tunnel — would be relatively contained due to water pressure around the tunnels.

The underwater system would have minimal impact on the landscape. Photo / Norwegian Public Roads Administration

The government is also working with the navy to look into risks of submarines crashing into the tunnel.

Norway hopes to complete the project by 2050. If successful, it will have beaten China, South Korea and Italy, which are also looking into similar infrastructure projects.