Archaeological sites on land have been a source of historical education for archaeologists for centuries. However, there are so many archaeological sites that are inaccessible from land, which is where underwater archaeology must come into play. Whether from wrecked ships, flooding of inhabited areas, or other underlying causes, the water is a treasure trove of archaeological sites that can be excavated to learn more about the past. However, the differences in on land versus underwater archaeology make the transition to learning about the underwater past difficult.

A few decades after scuba was invented, underwater archaeology had a boom in popularity, albeit a small one. From the 60s through the 1990s, archaeologists worked more underwater, eventually creating two schools: one for previously on land submerged sites, and one for ships (Bass, 1998, p. 52).

Archaeological diver excavating underwater (O’Connor, 1989, p. 26)

Despite the growth in popularity, it remained far more difficult, in both resources and labor, because of the sheer difference to on-land archaeology. While they share an end goal, as well as some similarities in process, the overall experiences are starkly different. Underwater archaeology is almost always done in low light situations, with almost no visibility (O’Conner, 1989, p. 28). It also requires archaeologists to be trained in both the schools of archaeology and safe diving practices. In addition to the rigorous training required for diving, underwater archaeologists who investigate wrecks must also be trained in recognizing ships and their design (Bass, 1998, p. 53), a second layer of training and expertise that makes archaeological diving a very niche and difficult to attain profession. Finally, divers using scuba technology to reach the bottom of the ocean must come up very often once the oxygen runs out, which is incredibly dangerous as their bodies depressurize and re-pressurize too many times in short procession (Keith and Frey, 1979, p. 26).

However, one big advancement in underwater archaeology has been made: saturation diving. This technology allows a diver to dive much deeper depths for a much longer time than scuba or other  underwater diving techniques because the diver does not have to decompress from the underwater pressure multiple times. Instead, the diver breathes special chemicals, and is kept pressurized for the entire time that they are underwater, so that they do not have to undergo depressurization sickness (Keith and Frey, 1979, p. 26).

There were, as of 1979, no archaeologists trained in saturation diving. However, in collaboration with industry, some nautical archaeologists were able to complete the excavation of the Secca di Capistello shipwreck. The divers were able to spend a total of 21 days underwater, and 157 hours completing excavation work, which would previously have never been possible at such a scale, as workers were before only getting about 5.5 hours of work done at a time (Keith and Frey, 1979, p. 27).

Diagram of Secca di Capistello diving setup (Keith and Frey, 1979, p. 31)

Even though saturation diving is far less accessible than scuba diving, its benefits on the field of archaeology are clear. Hopefully the importance of investigating underwater archaeology will inspire more collaborations like the one at Secca di Capistello, or inspire more nautical archaeologists to become trained in safe saturation diving practices.

For more information about saturation diving and underwater archaeology, please visit:

https://marineprotectedareas.noaa.gov/toolkit/underwater-archaeology.html

https://www.nationalgeographic.com/culture/article/under

water-archaeology

https://science.howstuffworks.com/science-vs-myth/everyday-myths/question640.htm

https://dan.org/alert-diver/article/saturation-diving/

Reference List:

Bass, George F.

  1998  History beneath the sea. Archaeology. Volume 51 (No. 6): 48-53

Keith, Donald H. and Donald A. Frey.

  1979  Saturation Diving in Nautical Archaeology. Archaeology. Volume 32 (No. 4): 24-33

O’Connor, Nessa.

  1989  Underwater Archaeology. Archaeology Ireland. Volume 3 (No. 1): 26-29