For a Florida homeowner, few things are more anxiety-inducing than the sight of a sinkhole, sucking in grass and concrete a few feet away from a home unable to move out of the way.
But a neighborhood in Ocala, Fla., is enduring something out of a homeowner’s nightmare. At least a dozen sinkholes are threatening homes — and draining all the water out of a retention pond — in the Fore Ranch community.
Neighbors and a prominent geologist worry that there is a bigger threat: More sinkholes may form, or they may combine into a mega-sinkhole.
“They just keep coming,” resident Maren Pinder told CBS-affiliate WFTV. “Are we safe? We don’t know.”
The giant dots in the landscape began appearing April 25, although there were neighborhood reports of a sinkhole problem as far back as 2012, experts say.
In the past week, several cars have been swallowed by the sinkholes, although no people have been injured, the Miami Herald reported.
And all the buildings in the Fore Ranch development are still standing — only one had to be evacuated because it is too close to a hole, displacing eight families, Meghan Shay, of the Ocala Police Department, told ABC-affiliate WCJB.
But the scariest thing may be what is yet to come.
It is possible that the sinkholes have absorbed all the earth they’re going to suck in and that the ground is stable, said David Wilshaw, the principal geologist with Britannia Solutions, which advises civil engineers and architects about how the ground will respond to development.
The worst-case scenario, however, could leave more gaping holes in the landscape — or just one very big one.
“If left untreated, certainly they’re going to keep growing and they’re going to intersect and coalesce,” Wilshaw told The Washington Post.
What has been a petrifying week for the people of Fore Ranch is the result of eons of geological weathering — and two decades of development, Wilshaw said.
A good chunk of Florida bedrock is made up of porous rocks such as limestone or sandstone, which can dissolve over time as they interact with acid naturally found in rainwater, according to the Florida Department of Environmental Protection.
As the limestone dissipates, the sand and clay and dirt above it sink, filling in the gaps. The process takes thousands of years, but can be accelerated by heavy rain, say, from a hurricane or a tropical storm.
The process that ultimately forms a sinkhole has been going on for millennia, long before Florida was Florida, and contributes to other underground cavities, such as the springs and caverns that dot the state.
But now there are houses and roads and golf courses in places that used to be open land, turning a naturally occurring geological formation into a disaster capable of swallowing someone’s house, Wilshaw said.
Construction on the community that would become Fore Ranch began in earnest in 2004, and developers built two retention ponds at the end of a system that funneled rainwater from roofs and streets, the geologist said.
But that aboveground transformation had unseen effects on how water drained below ground, which, for obvious reasons, can be difficult to ascertain.
In 2012, after Tropical Storm Debbie, nearly 14 sinkholes formed around one of the lakes, Wilshaw said.
And last week, areas near the community’s other retention pond became dotted with sinkholes, including several that completely drained the water.
For people who live in Fore Ranch, the gaping voids mean an uncertain future.
They’re hoping to avoid anything like what happened in the nearby community of Land O’ Lakes, where a sinkhole swallowed all of one house and most of another last summer, a tragedy caught on video that rocketed around the world.
To prevent that, crews have been seen in Ocala all week, using drilling machines and geological equipment to ascertain the scope of the problem and, residents hope, to come up with a solution.
Until that happens, all residents can do is warily watch the holes.
“It gets bigger every day,” Christina Carter told CBS News. “How far is this going to get, how big is it going to get, and nobody is telling us anything.”