The tragic incident of a Seffner, Florida man buried alive when a sinkhole opened under his bedroom last Thursday night, has created a new source of concern for Florida residents. The bedroom floor, furniture, and Jeff Bush, 36, were submerged in the huge 20 feet deep by 25 feet wide sinkhole. As the sinkhole grew deeper and wider, it became impossible to rescue Bush's body. On Sunday authorities demolished the house near Tampa, and two neighboring homes were evacuated as a precaution fearing the possible widening of the sinkhole.
Sinkholes are not rare in Florida, but the national media publicity associated with the Seffner tragedy provided information that Florida is more susceptible to sinkholes than any other state in the U.S. This news has driven fear into homeowners and occupiers as to whether they are living on a possible sinkhole that could cave in and swallow them and their home.
Miramar resident and retired geologist Kurt Andrade, says sinkholes are common to Florida because the land mostly comprise of a bed of sandy soil over another bed of limestone. Over time the limestone, a porous rock, naturally erodes through exposure to acidic water caused by rainfall that filters through decaying plant debris. As the limestone erodes, voids or small caves are created in the limestone underground. The larger these voids grow the more likely it is for the sandy soil atop of the limestone rock to cave in creating a sinkhole.
Andrade said although geologists can carry out tests to determine if sinkholes exists on residential properties, these tests are not "absolute" as a test conducted one day can determine the area is sinkhole free, then a few days later the limestone on the property weakens creating sinkholes thereafter.
The owner of the house in Seffner said an examination for sinkholes on the property was conducted last August, indicating no sinkhole danger.
Andrade says there're tell-tale signs that suggest a house could be sitting on a sinkhole. These include cracks in the walls that gradually lengthen or widens, and growing irregularity in the level of floors, especially the levels of tiles or wooden floors.
Responding to the question of if the land in South Florida is stronger than other parts of the state, and if sinkholes are as susceptible in the region as in north and central Florida, Andrade said, "There are similar dangers in South Florida, but the topology of the soil is different. There's a deeper layer of sand on the limestone, so if and when sinkholes occur they are usually wider and hardly not as deep as the Seffner sinkhole, but, yes, they can create structural damaged."
Unfortunately, most South Florida homeowners aren't sinkhole savvy and few concern themselves with insurance coverage against damage from sinkholes, although state law requires property insurers to provide sinkhole coverage.
However, even where homeowners are aware of sinkhole danger, many are unable to afford coverage. Most South Florida homeowners have no option but to purchase property insurance from state-owned Citizens Property Insurance. In 2011 Governor Rick Scott signed a law removing the 10 percent cap Citizens had for sinkhole coverage, allowing the company to increase this coverage as high as it needs to help meet its expenses.
Jerry Lampart, president of a Plantation homeowners association, says with the information arising from the Seffner tragedy, "It's obvious the state needs to take action to ensure homeowners have better sinkhole coverage, as now we know they are a real danger."