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Why an Underwater Habitat?
Underwater habitats are useful because they provide a permanent working area for aquanauts
(divers) who have a lot of work to do at depth. The principle behind an underwater habitat is a
concept known as saturation diving – when divers remain below sea level, their bodies acclimate to
the pressure by accruing concentrations of inert gases in the bloodstream. This is why when
returning to the surface they are at risk for decompression sickness, or the bends. With saturation
diving, they remain submerged until their blood is saturated with these gases; they only surface
once, so less time is wasted reacclimatizing to the surface pressure. The research that is done in
these facilities benefits a wide variety of fields, in particular space science (Hellwarth). Divers
remaining deep underwater are in a similar situation to astronauts who stay in space for extended
periods of time – in both scenarios, they are away from what they are familiar with, and are placed
into unfamiliar and hostile environments far from their natural habitat.
What are the different types of Underwater Habitat and how do they differ?
There are three main types of underwater habitat that are distinguished from one
another by how they deal with water and air pressure. The first type, open
pressure, has an air pressure inside that is equal to the water pressure outside.
Decompression is required for divers returning to the surface from this type of
facility, but they are able to go in and out of the laboratory on diving missions with
relative ease, due to the fact that they don’t need to acclimate to differing
pressures from the water and within the facility. These facilities use air locks and
moon pools to separate the inner habitat from the cold outer ocean. The closed
pressure habitat has an air pressure equal to atmospheric air pressure at the
surface, meaning that a diver can go from the surface to the lab without having to
acclimatize to a change in pressure. A closed pressure system also allows for
delivery of supplies via submersibles that are at the same pressure. Like open
pressure habitats, closed pressure habitats also use air locks to regulate access to
and from the facility a combination of these two systems is the third type of habitat,
one that has both an open and closed pressure system as part of the same habitat.
Divers are thus able to go from the lab to the outside using the open pressure part
of the habitat, and from the lab to the surface using the closed pressure area of the
habitat (Orbital Vector).
What is the History of Underwater Habitats?
The idea of saturation diving to eliminate the costs, monetary and health-wise, associated with the
time-consuming process of acclimatization from deep dives, was the ingenuity of a Navy doctor,
Captain George F. Bond, in 1957. By keeping the diver at the same pressure until the mission was
completed, physiological damage from decompression sickness would be reduced
(HowItWorks.com). Jacques Cousteau from France and Edwin A. Link from the United States
developed projects based on the idea. Two divers lived for a week 36 feet beneath the surface in
Cousteau’s first habitat, Conshelf I. Conshelf II, in 1963, held five men for a month and had a port
for a submersible called a diving saucer, so-called for its resemblance to the flying saucers of
science fiction (Cousteau Society). Conshelf III was the first underwater habitat with its own
compression system in 1969. Link’s original project, called Man-In-The-Sea, was a capsule with a
diver inside that submerged to 200 feet below the surface for 24 hours. The U.S. Navy took his
idea and ran with it to create the SEALAB program which, alongside NASA’s space program, took
man to new extremes. In 1964, four divers lived for eleven days 192 feet below the surface off the
coast of Bermuda in SEALAB I, an open pressure laboratory. SEALAB II, in 1965, in La Jolla
Canyon off the coast of California, three teams of divers were submerged to 62 meters for 15
days. One diver and astronaut, Scott Carpenter, set a record by being underwater for 30 days.
Unlike SEALAB I, SEALAB II had hot showers and refrigeration. 186 m deep off the coast of San
Clemente, California, SEALAB III was not very successful. Plans for divers to spend 45 days
underwater never happened as SEALAB had its first casualty, a diver succumbing to carbon
monoxide poisoning while attempting to repair the leaking laboratory. His name was Barry L.
Cannon (U.S. Navy Museum). The SEALAB program became the Tektite program, with the
Tektite habitat built by General Electric being used by the U.S. Navy. Divers with that program set
the record by being underwater for 60 days (Dmitrityeva). After Tektite came the Hydrolab, in use
from 1970 to 1985 for 150 missions off the coast of the U.S. Virgin Islands and the Bahamas,
primarily studying the effects on human physiology of remaining at depths for extended periods of
time. After that came Aquarius, a habitat still in operation (One World One Ocean). It is in the
water of the Florida Keys and hosts an array of high tech computers, allowing dives lasting for up
to 9 hours that study the beautiful coral reefs of the Keys. MarineLab has also been submerged in
the Keys since 1985, 27 feet below the surface, playing host to many marine biologists who study
the lagoon it resides in and the wrecks and artifacts strewn across the ocean floor. Next door to it
is the Jules’ Undersea Lodge, the world’s first underwater hotel with full amenities. Over 10,000
people have stayed there, including movie stars, athletes and politicians, as well as scientists from
the laboratory next door (Jules Undersea Lodge). The Scott Carpenter Space Analog Station was
also submerged in the Keys for its missions. The use of underwater habitats simulating space
environments shows how broadly the research from these underwater laboratories can be applied.
An artist’s conception of Sealab III
What is the Technology used in Underwater Habitats?
To access an underwater lab, divers sometimes swim or take submersibles
which then dock with the facility. Shallow habitats may even be accessed by
climbing a ladder or taking an elevator. Deep-sea labs have been taken by crane
from a boat and placed in the sea. In those labs deep underwater, it becomes
dangerous to breathe in the same air as on the surface because the nitrogen
that makes up 78% of the air we breathe has harmful effects in the bloodstream
at those pressures. Instead, a mixture of helium and oxygen is breathed;
however, breathing helium disperses body heat more rapidly and causes a
modulation in frequency when speaking, which can then create a communication
barrier. To combat the heat problem, underwater habitats are built with thick,
heavy insulation to keep them warm and comfortable for the divers who will stay
in them. The water around the facility can be as chilly as 32 degrees Fahrenheit;
fortunately, even deep below the sea it is possible to take a hot shower using
water pumped in from the surface. Underwater habitats have been built using
strong metals, most often reinforced steel (Orbital Vector). Their designs are
rounded or spherical in order to equalize pressure from the inside. Submarines’
characteristic oval shape comes from the same logic; a rounded form disperses
pressure more efficiently than does an angular form. Up to this point, underwater
habitats have used “umbilical cords” to maintain contact with the surface. These
cords provide hot water, electricity, communication, air and even television from
the surface. A diver named Lloyd Godson recently made waves by building his
own underwater habitat, and using a green algae, Chlorella, to produce his own
air. With a device called a Biocoil, he harnessed the power of photosynthesis to
replenish his air supply and recycle the carbon dioxide he exhaled (Scheffler).
He also used a stationary bicycle to generate some of his electricity, though he
used an umbilical cord to make sure that he would survive. In the future, it is also
possible that power will be generated using the power of the waves on the
surface, or from geothermal vents at the bottom of the sea.
The air we breathe at the surface contains 78% nitrogen, but the gas mixtures
breathed by divers substitute helium or a mixture of helium-hydrogen in place of
the nitrogen to prevent harmful bubbles in divers’ bloodstreams
What is the future of Underwater Habitats?
As technology evolves, more underwater habitats can be expected. Artificial
gill technology will allow respirators to harvest breathable air from the water
outside of the habitat. Power may be taken from sources in the environment
the habitat is placed in, eliminating the need for umbilical cords to the surface
(Scheffler). Dennis Chamberland, a marine researcher, is busy at work on the
Atlantica expedition, a permanent undersea habitat populated by a ‘family’ of
researchers (“Futurist”). It is reminiscent of fiction, such as the book Sphere or
the videogame Bioshock in its hope and ambition. Underwater hotels in Dubai
and Fiji are already under construction, with Dubai’s Hydropolis estimated to
cost $550 million to complete (HotelClub.com). Compared to outer space
missions, however, underwater habitats are rather cost-effective. For
instance, the entire SEALAB program cost $20 million versus the $20 billion it
cost for NASA to put man on the moon. NASA’s missions this century, which
have been discontinued due to budget constraints, have been estimated to
cost $450 million each, according to some estimates, whereas Aquarius’s
operation costs $3 million per year (Hellwarth). Both space and underwater
research are important and should continue to be funded going into the 21st
century. The knowledge gained from these missions beyond our normal way
of life provides wonder to the world and its discoveries and technology have
countless applications. It is vitally important that we not give up on these
science programs and continue funding them into the future.
The picture above shows the conceptual design of the Atlantica vessel, an
undersea laboratory sponsored by Dennis Chamberland.
Literature Cited
Bergman, Jennifer. "Temperature of Ocean Water."Windows to the Universe. Windows to the Universe,
16 2011. Web. 9 Dec 2012. <http://www.windows2universe.org/earth/Water/temp.html>.
Bilton, Peter. "Jacques Yves Cousteau: the Man Who Taught the World About the Mysteries of the
Deep." Knoji: History. Knoji, 20 2010. Web. Web. 9 Dec. 2012. <http://history.knoji.com/jacques-yves-
cousteau-the-man-who-taught-the-world-about-the-mysteries-of-the-deep/>.
Dmitrityeva, Tanya. "Tektite Habitat." Prezi. N.p., 24 2012. Web. 9 Dec 2012. <http://prezi.com/clqjkek-
h2hg/tektite-habitat/>.
"The Futurist Interviews Dennis Chamberland, director of the nonprofit League of the New
Worlds.."Futurist. 42.5 (2008): n. page. Web. 10 Dec. 2012.
Hellwarth, Ben. "The Other Final Frontier." New York Times. 21 2012: n. page. Web. 9 Dec. 2012.
. "Jules Undersea Lodge: Overnight." Jules Undersea Lodge. Jules Undersea Lodge. Web. 10 Dec
2012. <http://www.jul.com/overnight.html>.
"People Under the Sea." Blow the Ballast!. Office of Naval Research. Web. 9 Dec 2012.
<http://www.onr.navy.mil/focus/blowballast/people/default.htm>.
Scheffler, John. "Underwater Habitats." Illumin: A Review of Engineering in Everyday Life. IX.IV (2007):
n. page. Web. 9 Dec. 2012. <http://illumin.usc.edu/163/underwater-habitats/>.
"Top Five Underwater Hotels." HotelClub Travel Blog. HotelClub.com, 20 2007. Web. Web. 9 Dec.
2012. <http://www.hotelclub.com/blog/top-five-underwater-hotels/>.
"Underwater Habitat" 29 October 2008. HowStuffWorks.com.
<http://science.howstuffworks.com/environmental/conservation/issues/underwater-habitat-info.htm> 09
December 2012.
"Underwater Habitats." Orbital Vector: Speculative Technology Database. Orbital Vector, 16 2010.
Web. 9 Dec 2012. <http://orbitalvector.com/Aquatic/Underwater Habitats/UNDERWATER
HABITATS.htm>.
"Undersea Labs: 50 Years of Living Underwater." One World One Ocean: Inspiring People to Protect
the Oceans. One World One Ocean, 12 2012. Web. 9 Dec 2012.
<http://www.oneworldoneocean.com/blog/entry/undersea-labs-50-years-of-living-underwater>.
United States. U.S. Navy Museum. Aquanauts and Sealab. Web.
<http://www.history.navy.mil/branches/teach/ends/aquanauts.htm>.
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Abstract
Underwater habitats are useful study environments for researchers including marine biologists,
psychologists studying the effects of prolonged periods of isolation in extreme environments,
and physiologists studying how life adapts to different pressures. The technologies used and
data gleaned from these studies have applications in space research, and in the future
underwater habitats can be used for industrial activity such as mining the deep sea, and
expansion of these technologies extends humanity’s reach across earth’s biosphere into its
oceans. Although implementation is relatively costly, it is worth it because of the important and
useful data that can be taken and the testing that is possible on subjects as varied as biology,
physiology, psychology and new technology.
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The picture above shows a diver outside of the Aquarius facility located in the
Florida Keys.