September 10, 2024 — The following was released by NOAA Fisheries:
For 3 weeks this summer, a team of experts set out on C-Innovation’s M/V Island Intervention to support the Mesophotic and Deep Benthic Communities restoration projects. This effort aims to restore vital seafloor habitats damaged by the 2010 Deepwater Horizon oil spill. This operation, which took place within and around the Flower Garden Banks National Marine Sanctuary, involved a unique combination of data collection methods, as well as some competition akin to the 2024 Olympic Games!
The mission objectives were to:
- Install new mooring buoys to prevent anchor damage to the seafloor in the sanctuary
- Collect samples of mesophotic and deep-sea coral species for lab rearing and propagation
- Collect additional biological, sediment, and water samples
- Remove invasive lionfish and large marine debris
- Complete habitat transect surveys
- Execute coral transplants to test propagation and outplanting methods
- Deploy equipment such as benthic landers and Autonomous Reef Monitoring Structures
The Pressure is On—Literally
Working at depth—in this case, several hundred feet below the ocean’s surface—takes some unique methodologies. Often, restoration teams deploy specialized equipment such as remotely operated vehicles to collect samples or observations deep in the ocean. In other cases—as with this mission—we also employ some good old-fashioned humans to get the job done.
Due to our specific needs on this expedition, we partnered with saturation divers from the Navy Experimental Diving Unit. These divers are expertly trained to work quickly and nimbly underwater for long periods of time. Saturation diving involves divers being at depth long enough to bring all the body’s tissues into equilibrium with the pressures of the compressed breathing gas in their tank. Most recreational and scientific diving requires divers to spend hours decompressing before returning to the surface after each dive. Saturation diving saves time by keeping the divers under pressure the whole time (cue: Freddie Mercury vocals).
This method requires specialized equipment and techniques to get the job done safely. While the divers live on deck between dives like everyone else, they have to stay within a pressurized chamber on board to ensure the pressure in their tissues remains consistent throughout the mission. Then, when it’s time to dive, the divers enter a diving bell that is lowered by a crane onboard the ship. Once lowered to the seafloor, the divers step out into the underwater realm and get to work.