The Curse Of Oak Island's Caissons Explained

The crew of "The Curse of Oak Island" isn't afraid to utilize every single means available in their relentless search of the remote Canadian island. There are several theories surrounding Oak Island, which range from the idea that there could be hidden pirate treasure buried beneath the surface, or that there could be Marie Antoinette's lost crown jewels located somewhere on the island, or even that Oak Island acted as an outpost for the Aztecs or Knights Templar (via History). With so many wild theories abound, it makes sense to bring in several different types of professionals and equipment in order to exhaust every possibility.

The brothers Rick and Marty Lagina have tapped an entire cavalcade of serious metal detectors, diggers, archaeologists, engineers, and historians to aid in their pursuit. One such crew member is the famous metal detector Gary Drayton, and he often scours the island looking for coins, jewelry, and other such artifacts. There's also Billy Gerhardt who knows a thing or two about heavy machinery, and he often helps dig the massive trenches and holes around the island.

Recently, the crew of "The Curse of Oak Island" has utilized an engineering structure known as a caisson — but what exactly is a caisson, and how does it help the efforts of "The Curse of Oak Island?"

Caisson is French for "large box," and according to the Merriam-Webster Dictionary, it's defined as "A watertight chamber used in construction work under water or as a foundation." For fans of "The Curse of Oak Island," an immediate mental image from Season 9, Episode 17, "Blast From The Past" should come to mind. This particular episode sees a caisson installed on the island in a spot that is believed to have a hidden tunnel buried deep, which could potentially lead to the speculative Chappell Vault.

In engineering, caissons are often used in the construction of bridges, ships, and dams, and generally come in three different forms -– box caissons, open caissons, and pneumatic caissons (via Brittanica). All three variations have the same function, though, and that is to provide a suitable workspace free of water by the use of water-tight seals and pressure. By submerging a caisson into water or water-logged environs, work crews are able to pump or remove the water and debris out through differing means, which allows them to work in areas that were previously inaccessible.

Considering that Oak Island is host to several swampy locations and completely surrounded by water, the usage of a caisson allows the Laginas and their Fellowship to plunge into depths that wouldn't be available or safe by means of a simple dig.