Your concern is very valid. Much of Florida is Karst topography, and when the water table is dry, underground caverns drain and collapse, causing sinkhole lakes.

The process occurs naturally, but is greatly accelerated during dry spells or over-pumping of the acquifer.

Check out Lutz, Florida on Google Earth. Its almost impossible to get sinkhole protection on your homeowner's insurance, even in S. FL where I live, even though there are no underground caves here.

These sinkholes appear overnight, sometimes in a matter of seconds, and can easily swallow up entire homes or businesses. When I lived in Winter Haven, FL (near Cypress Gardens) one opened up under a Porsche dealership. Scores of beautiful roadsters and a fine showroom wound up under water.

But we never heard these things like the folks in Wisconsin are reporting, (unless you lived next door to the collapse).