If there’s one place I never want to be, it’s in an underwater cave. And even worse than that, I never want to be in an underwater cave that’s experiencing an avalanche.
Unfortunately for Kenny Broad, an environmental anthropologist, and his team of divers, they experienced just that while exploring a “blue hole” cave in the Bahamas. And they captured the heart-pounding moments on video.
The “blue hole” caves in the Bahamas are particularly rich laboratory environments because they hold clues to past climate conditions and supply drinking water to many communities. They also harbour a vibrant and diverse population of multicellular organisms.
But these caves remain mostly unexplored because they’re incredibly challenging and dangerous to manoeuvre. Some can plunge a staggering 600 feet below sea level, according to National Geographic. And not only that, but they can contain labyrinth-like passageways and mazes that run for miles in all directions. The visibility is so low that explorers can barely see inches in front of them.
“It’s a pretty good challenge to go into an underwater cave and come out alive,” Broad told National Geographic. “Imagine turning the lights off in your house and putting a blanket over your head and then trying to find your way out.”
Because of this, teams of divers always run guidelines along their path to help them navigate out.
In the video, as Broad and his team shimmied through the narrow passageways, “all of a sudden it just started raining down on top of me,” Broad says. The kicks of their fins or the “pressure waves from their bodies,” Broad says in the video, must have set off this avalanche of silt.
Luckily Broad was able to find the guideline and his dive partner and get out of there before becoming totally overwhelmed by the avalanche.
National Geographic released the video of their ordeal on Oct. 8. Watch it in its horrifying entirety below.
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