Have the Florida Everglades reached the 'tipping point'?

February 14, 2017, 2:47 p.m.
Mangroves in Everglades National Park in Florida
Photo: littleny/Shutterstock

The Everglades, a 2-million acre system of swamps and wetlands in South Florida, is running out of freshwater. That's the sobering conclusion of an extensive 16-year study by more than 80 scientists from 29 organizations, including the state’s major universities, the National Park Service (NPS) and the South Florida Water Management District.

Florida International University aquatic ecologist Evelyn Gaiser told the Miami Herald that the region has reached a “tipping point,” where change is becoming such a constant that the area is spinning into a cycle of decline.

What's causing the problems?

The Everglades is a mix of freshwater and saltwater areas. The freshwater is supposed to flow from the Kissimmee River into Lake Okeechobee and continue south into the Everglades. (It also comes from rainfall; NPS says the area receives about 60 inches a year.) However, decades of flood control have changed that historic flow, and ocean levels are rising, meaning there's more salty seawater in the mix. Plus, farms and cities are polluting the lake, sending dirty water downstream.

As the Herald reports:

The mangroves ringing the coast are moving inland, overtaking vital freshwater marshes. Growing swathes of peat, the rich mucky soil that formed over a few thousand years, are collapsing. And periphyton, the spongy brown mats of native algae that form the foundation of the food chain, is shrinking.

If damage to the largest subtropical wilderness in the United States continues, rare and endangered species like the manatee, American crocodile and Florida panther will face further habitat loss. A more far-reaching consequence is a shrinking defense against greenhouse gases.

“The threat here is we’re changing the system from one that is very good at sucking carbon dioxide out of the atmosphere, to one that’s very rapidly losing it," said Gaiser.

Several conservation and restoration projects are underway. As the Associated Press reports, reservoirs are being constructed near the lake to hold more fresh water, treatment areas to scrub pollution from farm runoff water have been expanded, and newly restored bends in the Kissimmee River are resurrecting floodplains and wetlands to clean and slow the flow of dirty water south.

These are promising efforts, but the future is uncertain. The National Academies of Sciences says at the current pace, fixing the Everglades could take another 100 years.