Nearly every weekend, cave divers slip into the chilly, turquoise waters of the Roaring River Spring near Cassville, Missouri, traversing the spring's underwater labyrinth in search of its end point. They have yet to reach it — but they've set a national record so far in their efforts.
The team, part of KISS Rebreathers of Fort Smith, Arkansas, consists of divers from across the United States. In November, team members Mike Young and Randall Purdy descended 472 feet from the surface, which experts say is the deepest explored cave destination in the United States.
Curt Bowen, vice president of ADM Exploration Foundation, which monitors diving records, confirmed the record.
To make it that far down, the divers had to squeeze past a restriction 230 feet down that kept two previous teams—in 1979 and 1999—from going farther.
Donning a wet suit and breathing apparatus, diver Gayle Orner said it’s the equipment that allowed the pair to go deeper.
"We're able to recycle our air. And...a lot of our gear is mounted on our sides," said Orner. "We have a very low profile in the water."
The divers use a piece of equipment called a rebreather, which essentially helps recycle a person's breath. This lets the explorers take smaller tanks and stay beneath the surface longer, she said.
On this day, Orner's job is to remain above the restriction and help out with a survey of the invertebrates in the cave. The team is working with a cave biologist from Texas A&M, she said.
"We're going to be trying to get an idea of the population of little isopods and amphipods that are down there that are cave adapted," said Orner.
The amphipods and isopods are pale in color and have no eyes. They’re adapted to living in a completely dark environment.
Collecting cave critters for research
Diver Eric Lee Hahn of Blacksburg, Virginia has filled various roles on the dive team—including collecting cave critters for study. That’s precisely what he was tasked with last weekend beyond the restriction inside Roaring River Spring.
"So shining your light, they pop out because the background and the environment's very dark, and they're so light," said Hahn. "But when the visibility in the cave—due to all the water flow and all the silt that's everywhere—is so low, it can still be very difficult to find them. Because you're barely able to see your nose or your hand, let alone the critters maybe many feet away from you."
Another diver last weekend planned to take special equipment around a large room past the restriction to get an idea of its diameter.
Hahn has gone past the restriction point on multiple occasions. He said just beyond that point is a massive "room"—it ascends to zero feet, where there’s a large air dome, and descends to the 472 feet underwater point that divers reached last fall.
Beyond that depth is a territory yet unexplored.
"That's why we continue to come back—to continue that discovery and exploration," he said.
Hahn said cave diving allows him to go where few people have gone before—and that's an incredible feeling.
"You know, fewer people have gone through this one location than have even been on the moon. The equipment considerations and the environments are very different, but at the same time, we each have entire life support systems that keep us breathing, keep us warm, keep us alive," he said.
Divers have a continuous guideline from the surface. When they enter a new area, they run a line and tie it off at convenient places along the way. That line, Hahn said, serves as the divers’ roadway or trail to get out of a cave.
Orner, Hahn and other members of the KISS Rebreathers dive team will continue their monthly weekend exploration of Roaring River Spring through November.
Eventually, a documentary about their dives at the spring and what they discovered will be featured at the Roaring River State Park Nature Center.