Florida May Be the U.S. Capital of Sinkholes

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The sinkhole that tragically took the life of a Florida man Thursday night may not be an isolated incident.

There are more than 16 verified sinkholes within a mile of the address in Hillsborough County, where a 20-foot-wide hole opened beneath the house, according to CoreLogic, the research firm that, it turns out, tracks sinkholes.

There are more than 15,000 verified sinkholes in Florida, the largest number in the United States, CoreLogic reports. The city of Springhill in Hernando County has earned the ignominious title of the city with the largest number of verified sinkholes at 3,145.

"It's important to note that not all sinkholes are prone to a sudden collapse like this, and they all obviously represent various levels of risk to people in the area," CoreLogic notes in a release. "It's also interesting to know, however, that general homeowners insurance often does not cover sinkhole losses."

Thirty-six-year-old Jeffrey Bush disappeared and is presumed dead after the sinkhole opened up under his family's home.

"Florida is made out of limestone,"  Hillsborough County spokesman Willie Puz told NBC. "There's a lot of groundwater that goes through the limestone and can erode the limestone away. As the water table rises and falls, sometimes those voids in the limestone can't support the weight that is on top of them, and they cave in."

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