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Transport / Mass transit

Norway is looking into building underwater bridges

Cool summer breezes drifting over the clear-blue water; snow-covered picture-perfect scenes in winter. It’s hard to imagine how life amongst Norway’s fjords could be anything other than perfect.

But, being us, we’re going to find something to complain about, and it’s probably going to be do to with transport.

The central artery of Norway’s western region, connecting the towns of Kristiansand in the south and Trondheim in the north, is Highway E39. It’s 1,100km long, which is about twice the length of the A1, but it takes a phenomenal 21 hours on average to slog along its full length.

That’s because it crosses seven major fjords, some as big as 5km wide and 1km deep, as well as several other smaller fjords, channels, or inlets. These can only be crossed by ferries, if the seas are kind, or helicopter, if they’re not. When you think about such vast obstructions, 21 hours suddenly doesn’t seem quite so incomprehensible.

You see the problem? 

The solution? “Underwater bridges”, sitting under 30 to 100 feet of water, with vertical tethers attached to the seabed, or to floating pontoons on the water surface. They’re technically known as submerged floating tunnels (SFT), and if employed along the E39 route they could cut travel times from 21 hours to 11 hours. For a route along which one-third of Norwegians live, that’s not to be belittled.

It sounds a deranged, futuristic idea, but it’s not really new at all. In 1865, an MP by the name of Sir Edward James Reed suggested the idea in Parliament as a means of crossing the English Channel. He was a naval architect and author alongside being an MP, and served as Chief Constructor of the Royal Navy from 1863 to 1870.

As a sign of the times, the idea failed to curry much favour in the Commons: MPs were worried it could be used as a method of invasion from the Continent, and his idea of a cross-channel submerged floating tunnel never got much further than fantasy.

The concept has since cropped up in various other guises, none of which is yet to get beyond the blueprint stage. In the 1980s, it was suggested as an option for a crossing of the Messina Strait between mainland Italy and Sicily, and it’s cropped up in Norway as a suggestion for projects including Vallavik, Høgsfjord, and Storfjorden.

The difference is that this time it might actually happen.

A cutaway of how the SFT would look. Image: Norwegian Public Road Administration (NPRA).

Arianna Minoretti, from the Norwegian Public Road Administration (NPRA) who are managing the project, says that each fjord has unique “characteristics”, and each will need its own solution. But she particularly likes the SFT option – or “hidden” bridge, as she calls it – and says it is particularly attractive as the technology and resources to construct such a tunnel have only just become feasible.

The SFTs also have the advantage of being, as the name implies, submerged, thereby not impacting on the beautiful landscape of the fjords in the same way as a regular bridge inevitably would.


For a lucky few who spend their time nipping across the fjords of Norway’s west, relief may be in sight. But what about the rest of us who don’t have the good fortune to live in such idyllic, if geographically drastic, climes?

A paper published in 2007 by a Norwegian academic and a group of engineering consultants looked into the possibility that such tunnels could be “extended perhaps by a factor of 100 or more” into imaginatively named “Very Long Tunnels” (VLT).

The primary purpose of such Very Long Tunnels? “To serve the developments in long distance travel in MAGLEV”, the super-fast train system by which trains float above the tracks using magnetic levitation (hence, Maglev).

The vision is that eventually such VLTs could be the conduit of a Trans-Ocean Tunnel (TOT) connecting either side of the Atlantic Ocean. One of the most obvious routes would be between London (or the British Isles more generally) and the eastern seaboard of the United States to New York.

One small step for Norway, then, and one giant leap for the future of intercontinental transport.

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