Aquarius Undersea Laboratory

ImageAquarius is an underwater laboratory and home to scientists for missions up to 10 days long, but to call Aquarius a home is like calling the space shuttle Discovery a mode of transportation. Aquarius is made to withstand the pressure of ocean depths to 120 feet deep. Presently, Aquarius is located in a sand patch adjacent to deep coral reefs in the Florida Keys National Marine Sanctuary, at a depth of 63 feet. The laboratory is attached to a baseplate that positions the underwater habitat (underwater laboratories are also called habitats) about 13 feet off the bottom. This means that the working depth of those inside the laboratory is about 50 feet deep. Located inside the 81–ton, 43 x 20 x 16.5–foot underwater laboratory are all the comforts of home: six bunks, a shower and toilet, instant hot water, a microwave, trash compactor, a refrigerator, even air conditioning and computers linked back to shore by wireless telemetry. Using Aquarius as a base for research diving expeditions definitely has its advantages. This is a side view of the Aquarius just prior to deployment in November, 1993.

Six aquanauts are housed during one to two week missions, about four miles offshore Key Largo in 60 feet of water at the base of Conch Reef in the Florida Keys National Marine Sanctuary.

  • 80-ton cylindrical steel chamber, 43 feet long and 9 feet in diameter.
  • 120 ton baseplate anchored to the seabed
  • 8 exterior viewports
  • 2 pressurized compartments or “locks” with separate life support control and communications; a main lock with kitchen, work area and 6-person bunkroom; an entry lock with large workspace.
  • Backup high pressure air, oxygen, CO2 removal, and medical supplies
  • Wet porch with open moon pool entryway and diver staging area
  • Real-time communications via Internet, video and cell phone
  • Undersea "excursion line" rope navigation system
  • Specially designed diving gear with twin 100 cuft scuba tanks and safety equipment, as well as umbilical diving with full facemasks/hard hats with communications and helmet cams


The Floorplan

 Floor Plan of the lab

Port Elevation

 Port Elevation

Starboard Elevation

 Starboard Elevation

Side cut away view

ImageThe special diving capability of Aquarius, called saturation diving, allows scientists to work out on the reef up to nine hours a day without fear of getting the bends, compared to one hour if they had to work from the surface. See the pressure lesson for more details.

Increased research time on–bottom is the key element that enhances scientific productivity beneath the sea. The support personnel enhance program productivity through diver training, and scientific and operational expertise. Safety is a hallmark of the program.

Life Support Buoy

Power generation, air compressors, wireless communications/telemetry array, and the capability to incorporate ocean observing sensor packages.



3 High-pressure air supplied undersea stations located as far as 1000' away from the habitat, allowing divers to communicate to the habitat and refill their scuba tanks while working on nearby sandy or coral reef areas.

Shore Base

Aquarius monitoring station/“watch desk”, fast response and workboats, small boats for daily operations, dive lockers, workshops, dormitory, wet and dry laboratories, and emergency recompression chamber.


  • 155 Mbps Wireless Bridge from Buoy to Shore, DS3 link to Internet
  • Multiple video feeds via web cams in and outside Aquarius
  • Polycom and Vbrick video conferencing and broadcast capabilities
  • Phone, broadband Internet and diver underwater communications

What is Aquarius made of?

The external envelope (main body) of Aquarius is made of 3/4" thick steel. This is the pressure hull that divides the entry lock and main lock. A 3/8" thick layer of insulation is located on the outer hull of Aquarius.

Aquarius consists of three main compartments: main lock, entry lock and wet porch. The two locks are part of the 43 foot long, 9 foot diameter steel tube. The wet porch is a 7 foot long x 10 foot wide by 8 foot high steel box. They connect together by watertight doors. The wet porch is open to the sea through its floor.

What things are taken into consideration when building such a structure?

First, where will the underwater laboratory operate? Water depth determines the thickness of the walls and viewports, the type of fittings for connections and plumbing, and much more. Depth also determines what kind of breathing gas system is required. Most people are surprised to learn that you can only breathe normal air down to a certain depth before it becomes toxic. Both nitrogen and oxygen cause problems when the pressure gets too high.

Aquarius consists of more systems them just the underwater laboratory on the bottom. The habitat itself, when full of air, floats. Therefore, it is attached to a 120 ton baseplate that serves to anchor it to the bottom. There is also a buoy, called the LSB (Life Support Buoy, that is moored above Aquarius. The LSB contains generators (for power) and compressors (for air). The buoy is connected to the habitat by an umbilical - a set of wires and hoses wrapped together in a special protective cover. The buoy also has radios that can send signals from Aquarius to the mission control - over nine miles away in Islamorada, Florida.

Another important consideration is related to what you want to accomplish using an underwater laboratory. In other words, why build an underwater habitat? In the past forty years, over sixty underwater laboratories were built, some were larger and some were smaller than Aquarius. Aquarius was designed to be more than just an underwater habitat for living. It is an underwater laboratory with wet and dry lab space, electrical and computer capabilities, and a comfortable living space for six people that allows the scientists to focus on their research. The Aquarius program is less about what happens inside the underwater laboratory. Instead, the value of Aquarius is defined by the work scientists do outside Aquarius, on the reef and in the surrounding ocean.

The Aquarius Reef Base is owned and operated by Florida International University (FIU).