Once the world’s largest producer of lead ore, the Bonne Terre Mine in Missouri is now home to the world’s largest freshwater scuba diving resort. The clear water is illuminated to give divers visibility more than 100 feet down.

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History of Bonne Terre

French settlers discovered the lead in Bonne Terre in the 1720s, giving the city its name which translates to good earth. The mine was founded in 1860 as one of the world’s first deep-earth lead mines. Using only hand tools, miners created the five-level cave system of over 457,000 square feet and 17 miles of shoreline. 

At one point, the Southwest Missouri Lead District produced 70 percent of the United State’s lead. Bonne Terre was also the world’s largest producer of lead ore. After lead ran out, however, the architecture of the mine made it difficult to bring in modern heavy equipment. The mine subsequently closed in 1962

After its closure, the water pumps which were installed to stop groundwater from flowing into the mine were switched off. Water gradually rose until the bottom three levels were completely flooded, drowning hundreds of feet of passageways and mining equipment. By the 1970s, a huge underground lake (aptly nicknamed the Billion Gallon Lake) had formed. 

The Mine Today

Underground boat tours in the Bonne Terre Mine

Not long after, Douglas and Catherine Goergens saw an opportunity to breathe new life into the unused mine. In the early 1980s, the mine opened up for public tours and, eventually, diving. Two of the five levels are not submerged, so visitors can take walking tours and boat tours. The walking and boat tour reveals the largest part of the mine where visitors can see submerged ore carts and abandoned wooden catwalks suspended 50-100 feet above the lake.

For certified divers, the mine’s fresh mineral water provides over 100 feet of visibility and a constant year-round water temperature of 58 degrees. Over 500,000 watts of stadium lighting illuminates the mine, giving divers the ability to clearly see sights such as calcium falls, rock formations, a submerged elevator shaft, lockers, a machine shop, and even an old cast iron drinking fountain.   

As Douglas Goergens explained, “Divers get to an area we call The City, about 80-100 feet deep…It’s like you’re going down a street in an old Western town. You’re imagining the activity at that time but no one is home. It feels like you’ve got into a time machine.”

Scuba diver in the flooded Bonne Terre Mine

A bucket list item for many tourists and divers, Bonne Terre Mine has been featured in many movies, hosted one of Red Bull’s World Championship Wakeboard competitions, and has been the venue for multiple venues. Jacques Cousteau, a sea explorer who co-invented the Aqua-Lung and changed underwater exploration forever, even visited the mine in 1983, spending five days filming there. 

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For more information on mines, check out our full episode HERE.