Norway engineers pioneer world's first underwater floating tunnel

The proposed floating tunnel would be a world's first. Photo / Youtube

Norwegian engineers have proposed a truly innovative solution to a travel difficulty faced by the picturesque country.

As a part of huge infrastructure project in Norway, engineers have proposed to build a world first floating underwater tunnel in a fjord - a long, narrow, deep inlet of the sea between high cliffs.

A major highway that connects the city of Kristiansand in the south to Trondheim in the north cuts through a number of fjords. The highway takes drivers on a 1100km journey but given the unique landscape of the nordic country it involves seven ferry trips to complete the drive.

The project would cut the fjord crossing time from 21 hours to 11 hours. Photo / Youtube

But the incredible proposal would cut the commute from 21 hours down to just 11 hours and also mean certain residents wouldn't necessarily need to rely on taking a helicopter to hospital.

Norway's public roads administration is currently preparing a feasibility study for one of the largest fjords on the route - Bjørnafjord. The structure will consist of two curved, 1200m-long concrete tubes hanging 20 to 30m below the surface. The tubes would be connected to floating pontoons on the surface.

The tunnel tubes would be connected to floating pontoons on the surface. Photo / Youtube

The structure is officially called a submerged floating tube-bridge but is also known as a Archimedes Bridge. The Archimedes principle is named after the Ancient Greek mathematician who came up with the buoyancy calculation, supposedly while sitting in the bathtub.

The principle denotes that the upward buoyant force that is exerted on a body immersed in a fluid, whether fully or partially submerged, is equal to the weight of the fluid that the body displaced.

Senior engineer for the country's public roads administration, Arianna Minoretti, told Wired that working on the project has been hugely exciting.

"For an engineer working on this structure, it's like being on the Discovery Channel every day," she said.