“Proceed with caution,” the signs warn.
The clear sparkling waters of Florida’s springs can be deceptive, making the bottom appear much closer than it is.
Many of the springs are attached to underwater cave systems that wind their way through tunnels, passageways and underground rivers that make up the state’s extensive aquifer.
“Recreational snorkeling and open-water scuba diving are welcomed at many of Florida’s State Parks, but for those who want to explore Florida’s underwater caves, you must be certified as a cave diver,” says Alex Cronin, spokesperson with the Florida Department of Environmental Protection.
Both the state of Florida and various cave-diving groups keep safety top of mind, posting signs at popular destinations for divers from around the world who come to Florida to experience the underwater world that dates back millions of years.
A Bit of Background
Wes Skiles Peacock Springs—one of most popular cave-diving destinations—was acquired by the state and subsequently opened to the public in 1993. Since its opening, Florida State Parks and the Department of Environmental Protection have required all cave divers to have proper certification and training.

“Cave diving is an intense sport, even more so for the early explorers who were just developing the skills, safety regimes and novel equipment unique to this environment,” says Sean Denney, who has cave dived in Florida since the early 2000s. “Their work paved the way for the sport to become safer, including developing the safety standards and laying the groundwork for today’s cave-diving certification programs.
“Over the years, the cave-diving certification process has evolved to further emphasize safety and conservation, to teach even more advanced skills, and to expand public education. As a result, it has become much safer.”
Statistics show a steady decline in fatalities among cave divers.
According to a 2016 article in Diving and Hyperbaric Medicine, from July 1985—when this data was first collected—to June 2015, the average number of fatalities has dropped from eight to three annually for all cave diving around the world.
Cave diving in north Florida began in earnest in the late 1960s, as recreational scuba divers wanted to learn more about the state’s underwater caves. Pioneers such as Sheck Exley were among the first to explore these extensive systems.
As they continued to dive into the unknown, explorers developed safety techniques and equipment, including non-tangling guide reels and bright underwater lights to help map the extensive underground water-filled labyrinths that laced northern Florida.
By 1973, the National Speleological Society had formed its Cave Diving Section to promote safety, education and exploration. Experienced members began to create a curriculum to provide training and certification for divers.
The NSS-CDS held its first cave diving instructor class in Branford, Florida, in 1980. It is the world’s preeminent cave-diving certification organization.
“The training has become more fine-tuned and now includes multiple levels of competency,” Sean says. “Each certification indicates a diver’s degree of skill and experience.”
Sean started his scuba career exploring reefs and wrecks in South Florida.
“It was the high level of training that drew me to cave diving,” he says.
A Cave-Diver’s Mecca
Sean started scuba diving when he was in high school.
“I grew up all over the place, but I’d always find someplace to free dive or scuba dive: Hawaii, Fort Lauderdale, the Keys,” Sean says. “But I wanted to do more, so I looked for a class that would teach me to get inside the wrecks—not just swim around them—and get safely out again. At the time, there were no certification courses for penetrative wreck diving, so I enrolled in a cavern diving class at a dive shop in Gainesville, where I was a student at the University of Florida.”
After that class in 2003, Sean was hooked.
By 2005 he was fully cave certified, completing both introduction to cave diving and full cave-diver courses. He completed more advanced courses in cave-diver propulsion vehicles and advanced trimix to extend his depth range as his experience in cave diving progressed.

“I knew that the northern part of Florida was the No. 1 cave-diving destination in the world, so it was perfect,” Sean says. “I could drive an hour or less and get in a dive, rather than drive to the Keys or fly to dive wrecks. I hung up my wreck gear and have never looked back.”
What is the appeal of cave diving?
“There’s so much to see in these underwater caves—giant rooms with fossils on the walls and ceilings, fish and other fauna that exist in the dark passageways, and the beauty of the underwater world,” Sean says. “Cave diving has so much more appeal because there is so much to see. I have always wanted to know what’s around the next corner, and cave diving satisfies that curiosity.”
He says the experience of cave diving is different for every diver.
“But we all know that it’s a sport that requires a great deal of discipline and deliberateness, every time you dive,” he says.
Cave diving is an integral part of Sean’s life. A graduate student at the University of Florida, Sean is a doctoral candidate in geomatics and a hydrographic surveyor researching water quality as it relates to the health of the cave systems and animal life there.
“My Ph.D. focus is two-fold: to map the underwater caves in both accuracy and precision using advanced technologies and to devise a legal treatise for the protection of underwater cave systems using both existing laws and proposing new laws where gaps exist,” Sean says.
He is president of North Florida Springs Alliance—a volunteer community group that supports work at five state parks: Wes Skiles Peacock Springs, Madison Blue Springs, Lafayette Blue Springs, Troy Springs and Suwannee River State Park.
Each is associated with springs, underwater caves, historic sites and hiking trails.
Membership is open to divers and non-divers interested in supporting these parks.
Sean has advice for aspiring cave divers.
“Find the right instructor and take your time at the various levels of training,” he says. “Once you’ve completed your full cave certification, find a mentor to help you discover the art and beauty of cave diving. One day, when you’re experienced enough, give back by becoming a mentor to new cave divers. That’s the best way to learn and understand the sport and the nuances that make it safe.”