The visionaries aiming to make underwater living a reality

“The sea,” wrote Jules Verne, “is everything. It covers seven-tenths of the terrestrial globe. Its breath is pure and healthy. It is an immense desert, where man is never lonely, for he feels life stirring on all sides. The sea is only the embodiment of a supernatural and wonderful existence. It is nothing but love and emotion; it is the Living Infinite.”

One of the enduring images from my childhood was an illustration from Verne’s Twenty Thousand Leagues Under The Sea (1870) showing Captain Nemo’s library on his submarine, the Nautilus. The meticulous engraving of this eccentric Victorian interior was in contrast to other, more sci-fi images I was bombarded with.

It was a childhood soaked in underwater fantasy. There was the trippy surrealism of Yellow Submarine; the curious, slightly sinister puppetry of Stingray with its undersea city, Titanica; the 1971 television movie City Beneath the Sea; and my own favourite, Voyage to the Bottom of the Sea. Then there was the TV series The Undersea World of Jacques Cousteau, and a string of Bond villains with their shark tanks and submersibles. All coincided within a brief window from about 1967 until 1976 when Jaws came crashing through the screen to kill off any lingering desire to live below the waves.

It seemed an intriguing confluence of fears and desires, this ideal of living below the sea, a moment which occurred during a period of nascent environmentalism, the cold war, the first moon landings and hippy ideas about the new Atlantis. The period left its own legacy of underwater ruins, glass-bubble “habitats” such as Cousteau’s Conshelf series (Continental shelf stations), which still sit at the bottom of the sea, the barnacle-clad equivalent of international space stations.

Now, 50 years after Cousteau’s first Conshelf was built off the coast near Marseille, the idea, if not quite the practice, of underwater living is coming back into fashion.

There is the breathtaking undersea restaurant at the Conrad hotel on Rangali Island in the Maldives and the futuristic designs by Polish group Deep Ocean Technology for the Water Discus hotel, planned for Dubai. But the project that has generated the most publicity is an ambitious and exotic vision for Katafinga Island in Fiji called the Poseidon Undersea Resort. The images circulating on the internet of rooms surrounded by shoals of exotic fish and colourful corals suggest you can already stay there but the project’s long delays attest to the particular problems of building under the sea.

“It has been difficult. But it’s not so much the technology,” says L Bruce Jones, president of US Submarines Inc, the designer behind the Poseidon Resort. “We also had a coup in Fiji and a financial crisis. Building a structure fixed to the sea floor isn’t that hard – there are far more problems in building submarines which have to be able to move.”

Living area in H2Ome

The research and testing carried out for the Poseidon resort have also prompted Jones to begin marketing what he sees as the next phase of undersea construction, an underwater house, or the “H2Ome”. Based on the technologies designed for the Poseidon resort, the H2Ome is billed on the company’s website as “the most technologically advanced undersea residence ever designed”, although, to be fair, the competition is not that strong. The plans show a disk-like structure lifted off the seabed on steel legs with a tube umbilically connecting it to the surface. “It’s circular in plan and 65ft in diameter, but the most important thing is that the interior is at one atmosphere – the same pressure as on land,” says Jones.

It is an important point. The biggest obstacle to underwater living so far has been the difference in pressure. “There have been about 70 underwater habitats built over the past 50 years,” says Jones, “but all of them have been at ambient pressure.” Under water the pressure is much greater, causing gases in the bloodstream to dissolve. This can result in the feared condition known as the bends, which can cause intense pain, and even death if divers return to the surface without decompression. The longer the period spent under water, the longer the decompression period needs to be, so that a couple of weeks under water may necessitate days of recovery. So the H2Ome, with its one atmosphere pressure, is a real advance.

Like space, being underwater is an alien and potentially deadly environment for humans, and just as with space stations (some underwater habitats were originally used to prepare astronauts for space), undersea structures can be tricky to build. “We manufacture in a dry dock,” says Jones, “and then the structures are floated out and sunk using a semi-submersible. We then build legs so that the structure stands above the sea floor for ecological reasons. It takes about 48 hours to fix the structure in place and hook it up to an umbilical central column [which supplies the services, power, oxygen etc.].” And what does one of these homes cost? “Well, that depends where it is.” For a site off the coast of Florida, for example, Jones says the bill would come to about $10m to build and transport the materials and another $500,000 to $1m to install the structure. With the extraordinary price of yachts though, it does seem extraordinary that no one has yet built an underwater house.

Michael Schütte, a naval architect and industrial designer, is founder of Brilliant Boats but previously worked on the H2Ome project with US Submarines. “Sure it’s expensive,” he says, “but compared with prime waterfront real estate or the cost of a tropical island villa, the $10m or so is actually pretty cheap. I mean, the H2Ome is 300 sq metres, three beds, three baths – it’s absolutely stunning. It’s not a lot of money for a house with a view on to a reef.”

Of course, the structures have to be extraordinarily robust and built to withstand not only the water pressure but also storms and hurricanes. Would there be any particular problems with maintenance underwater? “We worked on a 25-year lifespan, but remember underwater structures won’t decay as fast as if they were on the surface because there’s less oxygen,” says Schütte. “You might want to haul it out every ten years to repaint it – and then you’d need the heavy lifting gear back again, but perhaps you wouldn’t want to keep it clean. You might want to encourage marine life to grow around it, which also protects the structure. You could even do gardening down there, with clams and coral and marine critters.”

Jones also points out the capacity for fish feeding. “We can build beautiful reefs and you can just press a button to feed the fish. We can even turn on light for a limited time so you can enjoy the view at night too.”

The Water Discus hotel, planned for Dubai

Apart from fish-feeding, what other kinds of entertainment might there be? “It’s a submerged villa,” says Schütte, “so anything you can have on land you can have here too. You might need somewhere to land your helicopter and park your jet ski above water and perhaps a swimming area at the surface surrounded by a net so the kids don’t get eaten by sharks.” The home would be connected to the surface via a cylindrical structure which contains a spiral stair and, suggests Schütte, “a James Bond glass elevator”, and is sealed with watertight doors. You might arrive by dinghy, but more likely is that the home would form part of a group and be accessed simply via a jetty.

The surface above the pod, in fact, becomes almost as important as the underwater environment. “Think of where all your oxygen is coming from. You might want all your services, heating, ventilation, air conditioning, desalination and so on at the surface too so they’re not throbbing away by your head as you sleep,” says Schütte. “And ideally you want to be no more than 15 metres down because about 97 per cent of all life in the ocean is in the top 10 metres. You could go as deep as 200 metres but you’d need extremely heavy-duty viewing ports and it would be completely dark.”

Those viewing ports are the raison d’être of the underwater home. The ideal material, it turns out is polymethyl methacrylate – usually better known by the trade name Plexiglas. It performs extraordinarily well under the pressure of water, better, in fact, than steel, while the curves give the material extra rigidity. US Submarines, which plans to open its own specialist manufacturing facility, has developed technology that reduces the joints between sections to less than a millimetre, maintaining the impression of a clear, uninterrupted vista.

If there has not yet been a single house completed underwater, it might seem fanciful to begin thinking about undersea colonies of the types found in watery sci-fi. After all, what would they live on? What would they produce? But recent research into the hot streams of water spewed from undersea vents has found a rich mineral mix emerging from beneath the seabed which could be collected and “mined”, accessing minerals far more easily than traditional mining methods. In addition, aquaculture and the study of the processes and chemical transformations in undersea organisms could provide a rich seam of research for everything from medicine to fuel.

Studies using algae are already producing extraordinary results. The algae is grown in special floating bags at the surface (so it is able to photosynthesise) and helps to filter the excesses of carbon dioxide produced in an underwater space, it also then provides a source of both biofuel and, potentially, food. Power might be generated from wave energy converters on the surface, those sea-floor heat vents or by harnessing the flow of huge currents like the Gulf Stream.

Colonies like these, though, seem to suggest some kind of dry-land disaster, the kind of scenario which prompts corporations in movies to establish “off-world” colonies and we are not quite there, yet. So the seabed looks like being left instead to the high-end market.

Sure there are hurdles and huge technical challenges, but, apart from the views of reefs and exotic sea creatures, there is one other very attractive feature. If you venture far enough beyond territorial waters, the seabed does not belong to anyone. Verne’s “living infinite” is free. Perhaps the last great pioneering land rush is yet to come.

All pictures of projects are computer-generated images

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