Undersea Colony: In search of Another Planet to Live In!

Undersea colony is constructed by a group of underwater habitats positioned on the sea bed.

Preeti Gaur
New Update

By Pushpendu Kar & Sumit Goswami, Ph.D Scholar, IIT Kharagpur


World population is growing rapidly from year to year. According to the United States Census Bureau (USCB) estimated current population of the world is 7.012 billion. Statistics show that global population is expected to reach between 7.5 and 10.5 billion by 2050. As the total land area of the earth is fixed, population density of the earth also gradually increasing.

This Increasing population density makes it impossible to live for human being on the earth. So, for accommodating this increasing population man has started to find several alternatives, which include finding for another planet where people can live.

Design requirements

Undersea colony is constructed by a group of underwater habitats positioned on the sea bed. Underwater habitats are underwater structure in which people can continue their daily normal life like eating, sleeping, working and other activities. Previously theses underwater habitats became equipped with fixed amount of resources for living a fixed duration of time within it. But recent technological growth has modified these underwater habitats. Currently some new underwater habitats allow supplying these resources externally through pipe or produce within the habitat itself. This new process will extend living duration of people inside habitats.


Suitable quality breathing air is one of the most critical environmental conditions along with others needing for human physiology to continue their live. Underwater habitat needs to meet these requirements to allow humans to live. Along with meeting these requirements, researchers need to concern about the physical environment (pressure, temperature, light, and humidity), the chemical environment (drinking water, food, waste products, and toxins) and the biological environment (hazardous sea creatures, microorganisms, and fungi) of underwater habitats. The science and technology behind the design of diving, diving bells, submersible vehicles, submarines, and spacecraft to meet human requirements can give some knowledge of design and development of underwater habitats.

Several private individuals and government agencies throughout the world have been involved to design and develop numerous underwater habitats since the early 1960s. At that time these underwater habitats has been exclusively designed and developed for research and exploration purpose, but due to growing trend of underwater recreation and tourism recently some of the underwater habitats have been provided for these purpose. Physiological process and limits of breathing gases under pressure, for aquanaut and astronaut training, as well as marine ecosystems are major research concerns of underwater colony.

Modes of design

There are three fundamental modes of design of underwater habitat as follows.

  1. Open to ambient pressure via a moon pool: In this mode of design air pressure inside habitats remain equal to the underwater pressure at the same underwater level of the habitat. In this case no physical barrier to entry and exit other than moon pool water surface exists. So, entry and exit to and from habitat is easier. Ex: SEALAB.

    Closed to the sea by hatches: In this mode of design internal pressure of the habitat remains less than ambient pressure and closer to atmospheric pressure. Here hatches and airlocks are main barriers to entry and exit to habitats. So, entry and exit is quite difficult in this case.

    Mix of both types of design: In this mode of design same habitat structure consisting of both types of compartments connected via airlocks. Ex: Aquarius.

Some existing habitats

Conself: In the 1960s a series of undersea living and research stations named Continental Shelf Station (Conself) was undertaken by Jacques Cousteau's team. Conself-I was the first underwater habitat constructed in 1962. Jacques-Yves had been developed it to record the observations of underwater life. It was submerged in 10 meters (33 ft) of water near Marseilles. At first a team of two members had spent seven days within this habitat. The first attempt for man to live and work on the sea floor became possible by the design and development of Conself-II in 1963. It was a starfish-shaped house submerged under 10 meter (33 ft) down in the red sea. A half-dozen oceanauts lived for 30 days in it. Cousteau developed another station, Conself-III in 1965, which was more sufficient and serving most ties with the surface. It was placed at 102.4 metres (336 ft) in the Mediterranean near the Cap Ferrat lighthouse, between Nice and Monaco. Six drivers lived in it for three weeks to perform several industrial tasks.

Sealab: United States Navy has been developed a series of experimental underwater habitats named Sealab to prove the viability of saturation diving and humans living in isolation for extended periods of time. Sealab expeditions has contributed a lot of knowledge, which advance the science of deep sea diving and rescue, as well as helped to understand of the The psychological and physiological strains humans can endure. Sealab-I was submerged at the coast of Bermuda in 1964 to a depth of 58 m (192 feet of seawater (fsw)) below the sea's surface. Sealab-II was launched in 1965. It was different from Sealab-I because it included hot showers and refrigeration. It was placed in the La Jolla Canyon off the coast of California; at a depth of 62 m. Sealab-III was a refurnished version of Sealab-II habitat, but was placed in water three times as deep.

: General Electronics was constructed Tektite underwater habitat funded by NASA, the Office of Naval Research and the Department of Interior. Four scientists from U.S. Department of Interior lowered down to the ocean bed in Great Lameshur Bay in the U.S. Virgin Islands on February 15, 1969 to start an ambitious diving project named as "Tektite I". In this project, the four aquanauts had established a new world record for saturated diving by a single team on March 18, 1969. Aquanauts returned to the surface after 58 days expedition of marine scientific studies on April 15, 1969. In 1970 The Tektite-II missions were started. It was a series of ten missions each for 10-20 days duration with four scientists and an engineer on each mission.

Hydrolab: National Oceanic and Atmospheric Administration (NOAA) has funded the project for constructing Hydrolab in 1966. It has been started to be used as a research station from 1970. It can accommodate 4 people at a time. Nearly 180 Hydrolab missions were taken place. Among these missions, 100 missions were conducted during early to mid 1970s in the Bahamas and remaining 80 missions in St. Croix, United States Virgin Islands, from 1977 to 1985.


Aquarius: Aquarius is an underwater habitat dedicated for underwater scientific research like few other underwater habitats. It is owned by the National Oceanic and Atmospheric Administration (NOAA) and maintained by the University of North Carolina-Wilmington as a Reef Base. It was located in the Florida Keys National Marine Sanctuary, adjacent to Conch Reef under 20 m (62 ft) of water. It was built in Victoria, Texas, in 1986.

MarineLab: The MarineLab is an underwater laboratory providing uninterrupted service since 1984 under the direction of aquanaut Chris Olstad at Key Largo, Florida for training of educational and scientific investigations from US Military investigations and pharmaceutical development. It is a longest serving seafloor habitat in history. This MarineLab project has been started in 1973 with the name MEDUSA (Midshipman Engineered & Designed Undersea Systems Apparatus) by students of United States Naval Academy. Then it was designed and build as part of their ocean engineering student program.

SCSAS: The Scott Carpenter undersea habitat was designed to be a very portable habitat and was first to be lunched from a boat. It was taken to schools, colleges, museums and other public venue. Dennis Chamberland was designed this habitat. It was the first habitat designed by him. It has operated a total of 12 weeks during summers of 1997 and 1998 in Key Largo, Floida. The primary mission of this habitat was to demonstrate the ways in which the ocean environment could be used as an analog to the space environment. So, it was formally known as the "Scott Carpenter Space Analog Station".

New World Explorer: The New Worlds Explorer is also a portable underwater habitat, which can be deployed and recovered from any municipal boat ramp just like any recreational boat. It is a two man habitat designed for optimal missions of days or weeks. The habitat system has three parts deployed together. Different parts are the habitat itself, its ballast block and its S3 system (Surface Support System).

Leviathan: The Leviathan Habitat mission has begun in 2009. It was a world record breaking 80 day mission. This undersea habitat designed specifically for the Atlantica Expeditions. It can accommodate four aquanauts during the extended undersea mission. The Leviathan is designed to maximize functionality in a restricted space.

Future research

Researcher has started to develop new engineered features, including a triply-redundant system of air conditioners, dehumidifiers, and air circulators. The oxygen supply will come from surface-mounted air compressors in conjunction with carbon dioxide scrubbing systems to absorb the carbon dioxide exhaled by the passengers. Power will be supplied by wind generators and a bank of solar panels. Plans have also been made to accommodate digital communications, a functioning laboratory, and an entertainment space. Researchers also found that, algae can serve a dual purpose: providing a source of oxygen through photosynthesis and being edible and rich in protein. The Biocoil provides a controlled, contamination-free environment and can be operated at much higher cell densities than with traditional systems. All these continuing innovations can open up new horizon to people with some new underwater colonies; those can provide a better and longer underwater life to a larger group of people.


Continuous research on underwater colony is going on by both government and private agencies. As the output of these researches, there are some undersea hotel, resort, restaurant, and city where people can stay for their amusement, recreation, expedition, and research purpose. We may also find some new innovative underwater structure in near future which can accommodate vast majority of people for a long duration of time. This can reduce population density and increased burden on the land. But along with these engineers and researchers also need to think about to do all these things effecting the environment as less as possible.