Late summer is a perfect time to go for an outdoor swim. Many in Florida, however, are finding that the crystal clear spring-fed swimming holes they used to frequent have turned dark with pollution and algae.
“We have about 1,000 natural springs in Florida, artesian springs, and they are across-the-board suffering from reduced water volume flow rates and they are across-the-board polluted with nitrate nitrogen,” says Bob Knight, the director of the Howard T. Odum Florida Springs Institute, in Gainesville, Florida.
Reporter Doug Struck grew up near Wakulla Springs, Florida.
“[It was] a place with water so vodka-clear it drew filmmakers, tourists and locals. We used to say you could flip a dime overboard and watch it hit the bottom 120 feet down. Schools of catfish glided in ethereal space as tourists oohed-and-ahhed in glass-bottomed boats above,” Struck says.
Marjory Stoneman Douglas, the famed biographer of Florida’s wetlands, called the springs “pools of light.”
Now, however, the lights are dimming. Wakulla Springs and many other are filled with algae.
“You just find strings of algae kind of hooked to the dirt, hooked to the rocks that are on the bottom and just sort of hanging and flowing in the current,” says Dan Pennington, an environmental planner in Tallahassee.
According to Pennington, the algae has been moving into the spring since 1980. Now it’s begun to cover everything.
Scientists blame the algae creep on human influence.
“Springs die of two human acts. One is over-pumping the aquifer that feeds the spring. And the other is putting nitrates into the aquifer and the source of nitrates are we human beings in the form of fertilizers, whether it's on golf courses, or lawns or crops. And also human waste as well as livestock waste,” says Jim Stevenson, chief naturalist at the Florida Department of Environmental Protection.
The polluted water has ruined what Struck and many of the other 200,000 tourists who visit Wakulla Springs every year remember as a magical swimming hole.
Struck reports the water visibility is so reduced that Wakulla now only retains one glass-bottom boat that’s so infrequently used it currently hosts a moorhen nest.
“The algae is a black fuzz that coats the bottom and sucks up all the light. The luxurious waving eel grass is pretty patchy, the schools of fish are mostly missing. The Wakulla Springs of my childhood swimming hole, the Wakulla Springs of jeweled luminescence, now exists only in memories,” Struck says.
The city of Tallahassee has spent more than a quarter billion dollars on an advance wastewater treatment plan to reduce nitrates in Wakulla Springs. That’s helped, but Struck reports that there are still thousands of homes with septic fields in the watershed of the springs.
“The nutrients from these septic fields drain quickly through the sandy soil, into the aquifers, and out into the springs, where they feed the algae,” Struck says.