As workers piled the last mounds of gravel on the sinkhole that engulfed a Florida man, geologists and experts say they expect to see more sinkhole sightings throughout the state in the coming years.
Urban sprawl, well-water drilling and fluctuating weather patterns all lead to sinkhole collapses and could bring more of the phenomenon to populated areas, said Jonathan Arthur, Florida's state geologist.
"As our footprint on the land increases, the likelihood we'll encounter sinkholes will increase," Arthur said. "The activity we engage in that affects the subsurface land and water can trigger sinkholes as well."
Sinkhole claims jumped from 2,360 in 2006 to 6,694 in 2010, the last year such data was collected, at a cost of $1.4 billion, according to a 2010 report by the Florida Office of Insurance Regulation.
However, a Florida law passed in 2011 has made it more difficult to compel insurance companies to pay for expensive subsurface testing for sinkholes, drastically decreasing the number of claims - and testing, said Anthony Randazzo, a former University of Florida geology professor and current president of GeoHazard, a company that specializes in evaluating sinkholes.
"We've seen a big downturn in insurance-related claims at our business," he said.
The sinkhole that opened under a home in Seffner, Fla., about 15 miles east of Tampa, was extremely rare in that it resulted in loss of life, Arthur said. There have been only two other deaths ever in the state related to sinkholes, he said.
At about 11 p.m. Thursday, Jeff Bush, 37, was in his bedroom in the one-story home on Faithview Drive when a 20-foot-wide sinkhole yawned directly under him, taking him, his bed and the rest of his bedroom furniture, according to Hillsborough County Fire Rescue.
His brother jumped into the hole to save him but had to be rescued himself by a sheriff's deputy. Five other residents, including a small child, made it out of the home unharmed. Two adjoining houses - one on either side of Bush's - were also evacuated.
Rescue workers called off the search for Bush's body over the weekend when the area around the hole became too unstable and a backhoe demolished the home earlier this week. On Tuesday, workers removed the home's concrete foundation and dumped the last of four truckloads of gravel to fill the hole, said Willie Puz, a Hillsborough County spokesman. Code enforcement officers were still trying to determine if the two neighboring homes would also be demolished, he said.
Another sinkhole was reported on Monday about 2 miles away, Puz said. That hole, located between the yards of two homes, was about 12 feet around and not directly endangering any home, he said.
According to CoreLogic, an Irvine, Calif.-based firm that analyzes sinkhole data, there are more than 15,000 verified sinkholes in Florida, including 23 sinkholes within a mile of the one that took Bush. There are more sinkholes in Florida than any other state, according to the firm.
Sometimes sinkholes are triggered by natural weather patterns. When Tropical Storm Debbie dumped 20 inches of rain on drought-stricken Florida last year, more than 200 sinkholes were reported across the state within a few days, Arthur said. The sudden dry-to-wet fluctuation caused underground limestone caverns to collapse, triggering the sinkholes, he said.
Other times, workers drilling a water well or new homes built atop of weak limestone formations can cause sinkholes, Randazzo said. As Florida's population continues to grow, so will the risk of sinkholes, he said.
In 2005, Randazzo surveyed a home about a half-mile from the site of last week's deadly incident on behalf of an insurance company. After careful subsurface testing, a weak underground limestone cavern was detected and 500 cubic yards of grout was trucked in to fill it up, saving the home from a sinkhole collapse, he said.
But such specialized testing is becoming increasingly rare in the wake of the 2011 law. Florida lawmakers passed the law in response to insurers' claims that too many of the sinkhole claims were frivolous and the tests expensive, Randazzo said. But the law may have swung too far in the other direction, he said.
Jeremy Bush, the victim's brother who tried saving him from the sinkhole, has said that someone came to the home a few months before the incident to check for sinkholes but told the family there was nothing to worry about.
"It's a real tough situation now that everyone's facing," Randazzo said.
USA TODAY, Rick Jervis