Underwater
Habitats[1]
Amanda
Kimberly Tan Hui Ting (amanda.tan.2013@law.smu.edu.sg),
1st Year student, Bachelor of Laws, Singapore Management
University
Executive
Summary
This
paper seeks to understand the need for construction of underwater cities, the
feasibility of such construction and the viability of adoption of this
alternative underwater living method in the future with the aim of looking at
this as a possible emergency evacuation solution to worsening global warming
levels. To explore these three issues, this paper will look at the historical
development of underwater habitats from the time humans began to dive and use
submarines to Aquarius the last standing underwater research base existing.
This paper will also look into current development of underwater habitats in
which the three of the most notable current underwater habitats will be
considered. Lastly, this paper will examine the future considerations of
underwater habitats in three parts. The first will be the feasibility of
building these underwater habitats, the possible socio-economic and
environmental implications that building underwater habitats will result in and
lastly some future projections that have been made about how underwater
habitats will be constructed and used in time to come.
Introduction
The
world today is warming up and global mean temperature is slated to increase of
between 1-3 degrees Celsius. (NASA, 2013) As
such, parts of our world such as Europe are projected to suffer from a higher
susceptibility of flash floods occurring inland, coastal flooding happening at
an increasing rate and an inflated amount of erosion due to storms and a rise
in the sea levels as well as the mountainous area suffering from incidences of glacial
retreat, all of which would make it increasingly untenable to live on land. (NASA, 2013)
This
paper would like to propose the solution of an underwater habitat as a possible
form of alternative habitat that could be used as an emergency alternative
living space or as a long term habitat should global warming continue to worsen.
This is with the assumption that global warming will be causing a rise in sea
levels and flooding that makes it unsuitable to live on land without taking
into consideration any other possible environmental damage that has not yet
surfaced as an effect of global warming.
An underwater habitat is defined as a physical
structure which enables people to work and live underwater. (Amador, 2012) and this
structure will be equipped with the full facilities to accommodate human life. Underwater
habitats need not solely be used as a solution for alternative living in light
of global warming. They can also be used for scientific research such as Aquarius
or as part of a tourist attraction for those who would like to experience
undersea living such as the Poseidon.
1.
Historical perspectives
The historical
perspectives in this section will be examined in two parts. The first would be to
examine the initial developments of underwater exploration. The second part
will be to understand humans’ experiences living underwater, touching on how we
developed from underwater diving to underwater transport in the form of
submarines to constructing underwater habitats which were habitable for short
periods of time.
1.1 Initial development of Underwater
exploration
The first time that humans experienced life
underwater would be arguably when they started diving. Although there have been
some reports of people in ancient Greek mythology using hollow reeds to breathe
underwater, the first time there was formalized diving for a length of time would
be when people began to use diving bells in the 16 century with its lower
portion exposed to the water and its upper part containing air compressed by
water pressure. This would allow them to breathe the air contained in the bell,
leaving it for short periods of time to explore their underwater surroundings. (Marine Bio, 2013)
Diving equipment was refined and another inroad into
underwater habitation which must be mentioned was the invention and development
of the submarine. Although many inventors had some preliminary ideas regarding
submarines before him, Robert Fulton invented one of the first successful
submarines in 1801 which had most notably, with surfaced and submerged
operations using different propulsion systems. It also contained containers of
compressed air which allowed a two-man crew to remain below the water for a
period of 5 hours. (Bellis, 2013)
1.2 Saturation Diving
A major breakthrough in the development of
underwater living was the development of saturation diving. This was explored
in Dr George F. Bond’s project, Project Genesis which aimed to prove that
humans could be able to subvert the difficulties of deep diving and experience prolonged
times at great depth. (Bedolfe, 2012) This
led them to develop a method of diving known as saturation diving. This is
where the pressure of the atmosphere inside the underwater habitat is equal to
the pressure in the water and creating a system of sustained pressurization,
allowing the divers to be able to be able to move in and out of the underwater
habitat without having to decompress between trips. (How Stuff Works, 2013) It was
also found that decompression could be postponed for a long period of time as
long as the diver had a sufficiently well-equipped habitat. The habitat would need
to have air that was constantly being circulated and that was pressurized to
equal the water pressure outside and an entrance hatch in the floor that allows
the aquanauts to enter and exit the habitat. The diver could go deeper with one
long decompression process when they wanted to come to the surface. Currently,
at Aquarius, another underwater habitat, one decompression process lasts for 18
hours. (Hellwarth, 2012)
1.3 Development of Underwater Living
The development of saturation diving led American
inventor Edwin A. Link to create a tethered capsule which he named
Man-in-the-Sea and lowered a diver in it to a depth of 200 feet (61m) for a
period of 24 hours. (How Stuff Works, 2013) Subsequently,
Jacques Cousteau built the Conshelf I (Continental Shelf Station One), which was
located 10m (30ft) beneath the surface near Marseilles, France and had 2 inhabitants
for a period of 7 days. (Bedolfe, 2012)
Subsequently, Conshelf II, constructed in 1963
continued to use the concept of saturation diving. It was structured with main depth
at a similar depth as Conshelf I with 6 inhabitants for a period of one month.
It had a further addition of a deep cabin, where 2 men stayed at a depth of 30m
(100ft) deep, permitting their bodies to undergo complete saturation with
breathing mixture of helium. They also had a hangar, containing a submersible
(the Diving Saucer), pioneering an operation of the submersible from an
underwater base. (Bedolfe, 2012)
Consequently, other habitats were built also
for the purposes of research.
One of the notable habitats built were Sealab
I, II and III under the Sealab Program. Sealab I was built almost 200 feet beneath
the water surface, located 25 miles southeast of Bermuda with 4 Sealab
aquanauts living here for 3 weeks. Sealab II followed soon after off the coast
of La Jolla close to San Diego, which put forward the used of a trained dolphin
to run errands. Sealab II which was located at a depth of 600 feet (183m)
however, was discontinued following the death of a diver. (How Stuff
Works, 2013) (Hellwarth, 2012)
Then there was the Tektite program which was
located off St John island in the U.S. Virgin Islands, had underwater habitats
which were only located at a depth of 45 feet but it involved 12 scientific
teams spending 20 to 60 days underwater which was a longer duration than most
other projects. (Hellwarth, 2012)
There was also a West German Helgoland project
which showed significant progress in underwater habitats as it was able to be
located in a colder climate in the waters of the North Sea. (How Stuff
Works, 2013)
Another such habitat was the Hydrolab owned by
the National Oceanic and Atmospheric Administration (NOAA). This was a 43-foot
tank that housed a laboratory and started as a project of the Florida Atlantic
University. It was later changed and bettered over time to play host to
numerous scientist-aquanauts in their missions that were run in the waters off
Bermuda and St Croix in the U.S. Virgin Islands. (Hellwarth,
2012)
Later, there was Aegir, the mainstay of a Hawaiian
marine research center that was tested by having it placed at the depths of
more than 500 feet. This was constructed with 2 identical chambers in cylinder
shape laid end to end and joined by a 10-foot circular-shaped diving station. The
structure was raised on to a platform and flanked, pontoon-like, by two thinner
cylinders which formed an unique system structure to manage the buoyancy levels
which provided the ability for it to be mobile. Once moved to a specific site,
Aegir could then be submerged and would surface as easily as a submarine would. (Hellwarth, 2012)
Subsequently, La Chalupa consisted of the added
features of system to control the level of buoyancy and a increased ease in mobility.
It was constructed to mimic a barge on the outside measuring 50 feet long and 20
feet wide and containing 2 tank-like chambers which were joined to form living
quarters. It was structured to be able to be able to take crews of five for a
period of a month and could be lowered to depths of a hundred feet. Now, it has
since been converted into Jules’ Undersea Lodge, which currently remains the
world’s only underwater hotel, located in about 30 feet of water in a Key Largo
lagoon in Florida Keys, at a shallow enough depth such that little decompression
is required. (Hellwarth, 2012)
2. Current
situation
There are
currently a number of underwater structures that have been constructed or are
being proposed in the world today but for the purposes of this paper, the three
structures that the author found to be most notable will be discussed.
2.1 Current
underwater structures in the world today
2.1.1
Jules Undersea Lodge
Jules Undersea Lodge, a underwater habitat that was
converted from La Chalupa research laboratory, is located in Key Largo Florida.
It stands at a depth of 30 feet below the water surface and provides about 600
square feet of living space to host 6 inhabitants. Notably, it stands an
estimated 5 feet from the bottom of the lagoon where it is located and contains
compressed air, which prevents water from rising and flooding the rooms. (Jules Undersea Lodge, 2013)
2.1.2
Poseidon Undersea Resort
Poseidon Undersea Resort is located in and
surrounded by a 7.8 square mile lagoon at a depth of 90 feet. It has not
started to take any visitors yet but is set to promote a revolutionary tourist
experience with the ability to accommodate 7,200 people upon opening of its
bookings, a 9 hole golf course and a
chapel to consecrate weddings. Tourism for the wealthy is likely to become one
of the main functions that underwater habitats will be serving should it
continue to develop. (Poseidon Undersea Resorts, 2013)
2.1.3
Aquarius
The last undersea lab still in operation now is
Aquarius located at a depth of 60 feet (National Oceanic and Atmospheric
Administration, 2013) , in Key Largo Florida and houses
scientists who research there on a fortnightly basis from April to November for
as long as the hurricane season allows. (Bedolfe,
2012)
Future
Considerations
In the
discussion of the future considerations, this paper will be considering it in
three parts. Firstly, the feasibility of underwater cities will be examined and
this paper will be looking at it in terms of the various components of the
underwater habitat and the ability to construct it in a manner that is
sustainable to human life before moving onto the other considerations that will
affect its feasibility. Next, the paper will at the implications that living in
underwater habitats will have on society from the social, economic and
environmental perspective and lastly, consider what are some of the future
projections of the structure of underwater habitats moving forward.
3.
Feasibility
3.1
Availability of Food and Water
Food is
likely to be grown using hydroponics as proposed by Phil Pauley in his design
of sub-Biosphere 2 which suggests that an underwater habitat should have a seed
bank to grow hydroponic crops. (Zimmer, 2013)
Alternatively, farming and aquaculture could be used in food production. (Chino, 2011) Cooking of
food underwater is possible but is often avoided because of its smell and that
the fumes seem stronger in static air. (Nuwer, 2013)
This may result in a need to find alternative ways of cooking the food such as
building a vending machine that is able to contain the smell and the fumes in
processing the food.
With
regards to the provision of water, it has been proposed that a viable option
would be to transport freshwater from the surface or create it through
condensation or desalination. This however, may not prove to be a very
sustainable water source and may run out especially in situations of nature
disaster where freshwater from the surface is not readily available. (Nuwer, 2013)
3.2
Availability of a sustainable energy source
There
are currently a number of ways that have been suggested to produce sufficient
energy to be able to power the underwater city sustainably for a long period of
time.
One
such suggestion would be as in the proposed design of the Water-Scraper by
Sarly Andre Bin Sarkum where it creates its own electricity through wind, wave and
solar power and is kept upright using a system of ballasts supported by a set
of squid-like tentacles which produce kinetic energy. (Chino, 2011) The
wave power is likely to be produced by wave energy converters on the surface of
the underwater habitat, through sea-floor heat vents or generated when the flow
of huge currents like the Gulf Stream are harnessed. (Heathcote, 2013)
Another sustainable method of energy production
in undersea habitats would be to use algae that is grown in specifically designed
floating bags at the surface to allow for photosynthesis and then harvested to
produce biofuel which can be used to generate energy as well as form a source
of food. (Heathcote, 2013)
3.3
Availability of the right composition of
gases
When the body is under a certain level of pressure,
it needs different amounts of the various air components and the specific air
composition that is necessary to support any given underwater habitat will be determined
according to the depth of the habitat. Hence,
below a certain depth, more measures may be necessary to maintain a certain
ratio of oxygen to other gases in the air such as that of nitrogen at 500 ft
(150m) and helium at less than 1000 ft (300m). (Nuwer, 2013)
Helium would
be used at greater depths as an oxygen and nitrogen mixture produces harmful
physiological effects but this too has its negative consequences as helium
carries off body heat so quickly that it causes the aquanauts to suffer from
cold and from communication difficulties because their helium distorts their
voices. (How Stuff Works, 2013)
One possible way of maintaining a constant supply
of oxygen could include the abovementioned algae or the growing of plants using
natural or artificial light which can act as a filter of the excesses of carbon
dioxide and produce oxygen through photosynthesis. (Heathcote, 2013)
Underwater
inhabitants would be able to move around the underwater environment by using
hookah lines which are hollow tubes up to 400 feet long which is connected to
their face masks or helmets and their living quarters. This allows both
breathing and communication. Alternatively, scuba tanks can also be used. (Nuwer, 2013)
3.4
Removal of human waste and other waste
products
Human
waste can be treated and released into the environment or cooked down to a fine
ash. The feasibility of such methods of disposing of human waste however, would
be dependent on the size of the colony as a large colony may result in an
inability to manage the substantial amount of waste created. (Nuwer, 2013)
Moreover, if the people staying in the underwater habitats were to produce
waste at America’s current level of waste production, which is estimated at 220
million tons of waste a year (Duke, 2013) ,
this rate of waste production is likely to be unmanageable. It is necessary
therefore to have education and environmental awareness programs such that the
people who live underwater would be aware of the need to reduce, reuse and
recycle and conserve resources, such that waste is not produced at a rate where
it cannot be effectively disposed of and significantly pollutes the surrounding
environment.
3.5
Possible effects on medical health
There
may be a risk of suffering from a condition known as the bends which can cause
pain and even death, should underwater divers return to the surface without
decompression. The time needed for decompression extends in direct proportion
with the amount of time spent underwater. This can be solved by constructing
the structure to have a pressure of 1 atmosphere[2] which is
the same as that on land. (Heathcote, 2013)
Living
underwater also limits the inhabitant’s access to sunlight. Sunlight is
necessary for the human body’s absorption of vitamin D which enables the body in
its absorption of calcium from food and supplements, strengthens the immune
system and prevents the elderly from suffering from osteoporosis. (Office of Dietary Supplements,
National Institutes of Health, 2013)
In
light of the deficiency of sunlight due to living underwater, solar lamps could
be used to provide inhabitants with the sunlight that they need to obtain the
necessary minerals and nutrients.
3.6 Durability
and maintenance of the underwater habitat
The
underwater city is likely to face structural deterioration and decay and would
have to be built to be robust to withstand water pressure, storms and
hurricanes. It is suggested that the best material to be used would be
polymethyl methacrylate or Plexiglass, which is able to withstand the pressure
of water better even than steel. Also, its curves provide the material with
extra rigidity. Currently, one underwater habitat prototype known as H2OME was
constructed to have a 25-year lifespan but it is likely to last longer due to
the reduced amount of oxygen at greater depths of the ocean. Cleaning and
maintenance, however, would pose a challenge due to the need to lift the whole
structure from beneath the ocean using heavy lifting gear. Instead, a more
viable solution would be to not clean the habitat and instead allow marine life
to grow around it, which would protect the structure. (Heathcote, 2013)
3.7
Finding the optimum depth in which to build
the structure
The
best depth to build the structure would be about 15 meters in depth because
about 97 percent of all ocean life is in the top 10 meters. It would be
possible to reach a depth of 200 meters this would require extremely heavy-duty
viewing ports and there would be no light. (Heathcote, 2013)
Moreover,
building these underwater structures at a level building deeper than 1,000 feet (300m) would cause
the structure to experience very high pressure at such depths (Nuwer, 2013)
and would be less feasible as it would need to be enhanced with very thick
walls.
4. Implications
Next,
this paper will examine the implications that having an underwater habitat will
create in terms of the social, economic and environmental implications.
4.1 Socio-Economic Impacts
4.1.1 Increasing the Income Gap
There
is a higher cost associated with living underwater as the underwater structures
are still very expensive to build. A site off the coast of Florida would cost
in the range of $10 million to build and transport the materials as well as
another $500, 000 to $1 million to install the structure at the desired
location. (Heathcote, 2013) As a result,
underwater living may later become the preserve of the rich and the poor would
have no choice but to live above ground and suffer from the increasing levels
of pollution and the threat of the harmful effects of global warming. This
would essentially widen the gap between the rich and poor and would be heavily
socially divisive.
4.1.2 Lack of public support for such programs
When
countries such as India decided to invest in a space program, there was
difficulty in sustaining public support for these programs because the people
were not able to draw the links between the space-based assets and the public
services that they can render to the population, being hampered by a lack of
scientific literacy. (M. Ansdell, 2011) Similarly,
people may not be able to appreciate the severity of the threat of global
warming which may cause them to feel that their governments are investing in an
unnecessary expense and not investing sufficient resources in more pressing
concerns such as trying to alleviate the widening income gap by investing in
distributing resources to the poor. This would cause displeasure and dissent in
the population which may lead to strikes and protests which would affect the
smooth running of the country.
4.2 Environmental
4.2.1 Ability to obtain better environmental
research
Having
an underwater habitat could lead to a significant increase in the amount of
undersea research. According to Tom
Potts, director of the Aquarius Reef Base, divers from the surface have about
an hour-and-a-half per day to do all their work. However, if they were able to
inhabit the bottom of the ocean for 30 to 60 days, it is likely that their
productivity could increase exponentially. (Nuwer, 2013)
Moreover,
there may be significant environmental resources that can be tapped on under
the sea. Recent research produced showed that hot streams of water spewed from
undersea vents produces a rich mineral mix emerging from beneath the seabed
which could be collected and “mined”, accessing minerals much easier than
traditional mining methods. Also, looking into aquaculture and the processes
and chemical transformations in undersea organisms may reveal new resources for
essential human needs such as medicine and fuel. (Heathcote,
2013)
That
said, there have been recent advances in the field of diving technology in
areas such as development of circuit re-breathers, devices that recirculate the
divers breathing gas. These devices are able to sustain the divers for extended
depths prolonged durations in excess of four to six hours which will facilitate
their exploration of the sea floor without the need for an underwater habitat
to provide a base from which one would carry out this research. (Amador, 2012)
This
could negate the need for underwater habitats in research in the future as one
would able to conduct all the necessary research using these devices. However,
there may still be health risks in the usage of these devices and hence it may
be more prudent to continue to have a underwater habitat to form as base which
the divers could return to should any mishap occur with regards to their diving
equipment.
4.2.2 Change in the ecological balance
Although
current experiments with underwater living have not surfaced any distruptions
to the ecological balance, there could also be a severe environmental and
ecological impact especially on the marine life because by introducing a
foreign component to the ecosystem, it may disturb the balance of the ecosystem
and conversely increase the likelihood of natural disasters of the sea and the
ocean. This may however, only surface after an extended period of underwater
habitat as distruptions to the ecological system do not surface the problems
immediately. This is something we need to keep in mind when building such
habitats and should identify any effects we may have on the marine ecological
environment and develop solutions to limit the amount of damage created as much
as possible.
4.3 Others
The
implications analysed in this section do not fall under any particular category
and constitute some of the author’s own thoughts with regards to other possible
implications that could surface which have not been raised in the sources from
which this paper took reference.
4.3.1 Inaccessible to people with special needs such as the elderly and the
disabled
The
elderly and the disabled are unlikely to be able to stay in these underwater
habitats as they would require to scuba dive into the underwater habitats which
they may face limitations due to their lack of mobility.
However,
Sue Austin, a disabled lady, has been able to use an underwater wheelchair to
perform a range of acrobatic maneuvers underwater which looks like underwater
ballet. (Austin, 2013) The underwater wheelchair
supports her body completely. This could be the solution for people with
limited mobility to eventually begin living underwater.
4.3.2 Solving problems of overpopulation
Although there is currently ample
underwater space as this space is still untapped, having a limit to the depth
that can be built for the underwater space would result in the space
constraints that countries experience on land to be translated to the
underwater space. Moreover, as every country would want to capitalize on this
underwater habitat to build an alternative living space in times of disaster,
this will exacerbate the problem and we may be merely moving the overpopulation
problem from above land to below land.
5. Possible future developments
In the
future, we are likely to use rapid deployment portable inflatable habitats to
facilitate our deep decompression dives, which have been projected to be able
to conduct even deeper dives.
Future
habitats could also be equipped with satellites to facilitate clearer and more
efficient communication. Moreover, underwater habitats were really to be
used as future emergency evacuation solution as according to Ian Koblick,
further technological advances may be needed to expand the current
infrastructure to be able to support a larger population as this will be
required to expand the systems for evacuation in emergencies and how air supply
and humidity is environmentally controlled. (Nuwer, 2013)
Future
habitats should look towards having increased depth and allowing for humans to
be able to spend a longer duration of
being underwater whilst being disaster proofed. Getting funding for support of
further development of underwater habitats may be difficult in the current
economic climate with foreclosures on homes on land in countries such as
America. A large part of exploration programs even in healthy economic climates
may also be considered unusual and may not be funded. Conversely, the way in
which funding bodies provide instant reviews and promote projects with high
risks that are aligned with current industry trends will be the driver that
promotes exploration in the field and will continue to spark off innovation in
this area.
Conclusion
In conclusion, people often fear what they do not
know but understanding the unknown is the first step to create innovation. In
light of the research found in this underwater habitats are likely to be a
viable alternative emergency and
evacuation habitat in light of the global warming problems in our world today
or even as a habitat used for tourism and maybe further in the future as a
permanent alternative habitat. However, more must be done to research into the
future implications that such underwater habitats. People may not be initially
receptive to such ideas as they might such an expense unwarranted but it is
through improved awareness programs they will be able to understand the
benefits of having an emergency evacuation strategy in the form of an
underwater habitat. The paper believes that it will only be a matter of time
before underwater habitats become our home.
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