TALLAHASSEE — It turns out the best way to predict sinkholes is to find the ones already there.
For two years, a team of sinkhole hunters with the Florida Geological Survey has been scouring the state to create a map of where sinkholes are most likely to form. They’ve trudged through terrain in 55 of 67 counties so far, using digital elevation maps and aerial photographs to ferret out known sinkholes and infer future ones. To twist an old saying, where there’s fire, there’s likely going to be more fire. Those additional fires is what the scientists are after.
By this time next year, the crew of 10 geologists and computer mapmakers expect to have the whole state platted to show areas vulnerable to sinkhole formation.
For the Tampa Bay area, nicknamed “sinkhole alley,” such a map could prove invaluable for local officials and others to gird for ground collapses after storms.
Sinkholes, however, aren’t always immediately obvious. They may be hidden in rural areas, surrounded by dense vegetation. Like a physician diagnosing a patient, “we refer to them as ‘symptoms,’” said geologist Clint Kromhout, the team’s leader.
For example, in their version of a doctor’s bag, geologists use a technology called LiDAR, for light detection and ranging. Laser bursts create a three-dimensional image of a particular area’s surface. Kromhout said they also use existing survey data from water management districts and the federal government in their hunt.
Even with existing information and high-tech aids, it’s not as easy as it sounds. Sometimes a bump in the ground is just a bump in the ground and not a sinkhole in waiting.