Tennessee Underground: Explorers shed light on the dangers and wonders of caving

Michael W. Aldrich | The Tennessean

Show Caption Hide Caption Bluegrass Underground's new home, The Caverns Bluegrass Underground creator and Caverns owner Todd Mayo spent the last 18 months turning a cave into a music venue.

Chuck Sutherland was setting up camp by an underground stream 300 feet inside a Middle Tennessee cave when he heard a loud smashing noise echo down the narrow passageway.

"That’s not the sound you want to hear when you’re underground," said Sutherland, 38, a member of the Tennessee Cave Survey.

"I really hope that’s not what I think it is," Sutherland thought to himself as he braced for a rogue boulder within Bonk Knob Cave — a subterranean labyrinth located in Van Buren County.

One of his fellow cavers had knocked the rock loose. It thankfully stopped shy of his position within the cave.

Sutherland says close calls like this happen all the time.

Tennessee has more caves than any other state, and its caving aficionados are refocusing on safety and responsibility in light of the recent events in Thailand — where seasonal rains flooded the entrance to the Tham Luang Nang Non cave, trapping 12 boys and their soccer coach for more than two weeks.

"In the summertime especially, flooding is a real problem because weather reports can be a little unpredictable," Sutherland said. "I know several cavers who have been trapped underground for long periods of time because of rain, and it’s entirely possible that you can die in a situation like that."

Dean Wiseman, 48, a member of the National Speleological Society, says the dramatic crisis and rescue in Thailand has shined a light on caving — and the importance of safety — in the United States.

"I think pretty much every caver I know was absolutely glued to the story in Thailand," Wiseman said. "It was an unfortunate thing, but also encouraging to see the success of such a complex and difficult rescue."

Tennessee contains 20 percent of the known caves in the United States, according to the National Caves Association.

"Tennessee has over 10,000 caves — and that’s just the documented ones. They find more and more every year," Wiseman said. "I’ve been caving in Tennessee since the early '90s. It's one of the top destinations for caving just because the caves are so huge and beautiful with such diversity."

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Sutherland says inexperienced cavers should start out at some of Tennessee's public caves, preferably guided by experts who can demonstrate cave etiquette and how to use the gear properly.

Here are the dangers new cavers should be aware of:

Hypothermia (wear layers and avoid materials like cotton)

Flooding (check the forecast)

Falls or falling objects (be aware of wet or loose rocks that can shift within a cave)

Bats and other cave critters (don't disturb a cave's biological life)

Although caves can be filled with geological and historical wonders, they are still wild environments so — just like a backpacking or hiking trip into the wilderness — cavers need to be prepared. Here are three hard-and-fast rules:

Have the right gear

Go in a group

Tell people where you're going

A big part of staying safe is having the right gear, according to Sutherland.

"We cave with helmets, knee pads, elbow pads, gloves, boots and then — depending on the type of cave you’re going in — synthetic fibers so you don’t catch hypothermia when you get wet," Sutherland said.

Another must is bringing three individual sources of light that can each function on its own without anyone or anything else. Sutherland said he prefers headlamps that keep his hands free.

Caving with a group is essential, as is always informing someone outside the group of the details of the expedition.

"If we’re going on a caving trip, we have someone not going on the trip who knows where we’re going, how long we plan to be there and when to call somebody if we’re not back in a certain amount of time," Wiseman said.

Because most wild caves are located on private property, it's important to respect others’ property and obtain the owner's permission before entering any cave, according to Sutherland.

Caving — or spelunking — is typically enjoyed for recreational purposes. However, there is a historical and exploratory aspect that also drives cave aficionados. For Wiseman and his family, one Tennessee cave in particular has left a lasting impact.

"I heard about this cave in Union County called Oaks Cave, which has a historical signature on the walls inside by the name of Alfred Oaks," Wiseman said.

"Well, my wife’s last name was Oaks at the time and — to make a long story short — we figured out that Alfred Oaks was her great-great-grandfather and this was the property that her ancestors had lived on and been displaced when the reservoir was put in. They had actually used the cave for storage and harvesting nitrates for fertilizer."

You may not find the signature of your great-great-grandfather, but nevertheless, check out Tennessee's vast underground network of caves.

Reach Michael at maldrich@tennessean.com.

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