The gist of the idea is to suspend an underwater tunnel from floating pontoons. By the time you finished reading that sentence, you probably already had a list of things in your head that seem to make this a terrible idea. After all, it does seem to combine the worst aspects of both underwater tunnels and bridges. But, the idea may actually be a good one, and it’s already being seriously considered in Norway.
You see, Norwegians have a fairly serious obstacle to long distance travel: fjords. The tradition way to cross a fjord is by ferry. One simply can’t ford a fjord – they’re just too deep. The deepest fjord in Norway, the Sogn, is almost a mile deep. That’s the same reason that a traditional underwater tunnel is impractical; putting a tunnel that deep underwater is inadvisable for a number of reasons, such as construction challenges, pressures at those depths, and unknowns about the seafloor itself.
A regular ol’ bridge could work, but presents difficulties of its own. The harsh weather would make travel across such a bridge dangerous, and you’d still have the age-old problem of getting ships under it. For those reasons, Norwegians usually stick to ferries for crossing their fjords – of which there are more than a thousand in Norway alone. But, an untested idea for a submerged floating tunnel may be just the solution they need.
It’s no secret that humans have an innate distrust of bridges, and that fear is dramatically amplified by the idea of being stuck under the surface of the frigid Norwegian Sea. But, if we can get past our fears, the proposed idea has a number of benefits. The tunnel being underwater protects it from the poor weather above, and ships would have no trouble passing above. As an added bonus, it maintains the picturesque beauty of the Norwegian countryside. However, it’s all for naught if no one will drive through it. Would you?