Florida Buys Longest U.S. Underwater Cave System
Florida has purchased land in Wakulla County that covers the longest underwater cave system in the United States, and the fourth longest in the world.
The underground river winds 19 miles through narrow and wide caves, including a huge room called the Black Abyss that is large enough to hold a small skyscraper, according to Mike Wisenbaker, a member of a volunteer dive team that has been mapping the system for more than 15 years.
More than 100 million gallons of water flow through it each day. “This is comparable to the Grand Canyon as a tremendous natural resource,” Wisenbaker said. “The only problem is no one on the surface can see it.”
Under the deal completed the day after Christmas, the state bought approximately 3,750 acres in northern Wakulla County from the St. Joe Company in a transaction negotiated by The Nature Conservancy.
The purchase protects 13 of 27 mapped sinkholes – places where the underground water briefly surfaces. Nine other sinkholes in the system are already protected on federal land.
The Wakulla system is well known to locals and divers worldwide, Wisenbaker said. Volunteer divers, as part of the Woodville Karst Plain Project, explore and map the variety of depths in the region’s porous limestone, deep fissures and sinkholes.
The depths range from 30 to 200 feet, where divers must use a special “trimix” of oxygen, helium and nitrogen. Decompression time in the water can be 15 hours, said Wisenbaker. The underwater current is so strong in some places that even divers being pulled through the water by cylindrical scooters must move off to the side and out of the current to make any headway.
The acreage is part of the Wakulla Springs Protection Zone, some 7,900 acres identified by state officials for protection around Wakulla Springs State Park. With this purchase, only about 900 acres remain to be bought.
The purchase contributes to efforts that would connect the St. Marks National Wildlife Refuge, the Wakulla Springs State Park and the Apalachicola National Forest. The linkage of these conservation areas will not only protect water resources, but provide a wildlife corridor for a wide range of species.
Most of Florida’s 600 freshwater springs are in the northern part of the state and originate in the upper region of the Floridan Aquifer – the source of 90 percent of the state’s drinking water. Protection of spring recharge areas is important since contamination is a major threat to Florida springs. Maintaining water quality, quantity and surrounding habitat is critical to the long term health of these systems.
Provided by theEnvironmental News Service.
