Frightening ‘underwater avalanche’ traps scientists (VIDEO)

© National Geographic
Most people are probably terrified of being trapped by an avalanche in the dead of winter. But environmental anthropologist Kenny Broad and his research team took that disaster even further – the explorers got trapped by an “underwater avalanche.”

The underwater cave diver was investigating one of the blue holes cave systems located in the Bahamas – water environments which have only recently started being researched.
Already facing limited visibility issues in the submerged caves, Broad and his team found themselves covered in sediment dust and silt, completely obscuring their visibility.

National Geographic cameras captured the harrowing experience and uploaded it to YouTube. Broad says that one of the members of his team’s fins or a pressure wave may have caused the initial avalanche.

“My initial reaction was to just scream in my own head,” Broad says in the video.

But the team had prepped for these kinds of events with a guideline, an expanding distance line used to help divers navigate the dark caverns and make it back to their starting point.

“We ALWAYS run a guideline. We place it very carefully, because you have to assume you’re going to come out in no visibility,” Broad noted at the top of the video.

“Without that line, you have low odds of getting out.”

The footage shows that Broad calmly found the guideline, giving a signal to his dive partner to push forward. While the team was lucky enough to have a narrow space to swim through, Broad says that a wider passageway would have made it nearly impossible to find the guideline.

Broad added that it wasn’t until he got back to the surface that he realized how intense the experience had been.

“That was one of the most tense 78 minutes that I’ve spent in a long time,” Broad says in the video after emerging.