Residents of north-central Florida are familiar with sinkholes that are caused by the slow erosion of the underlying bedrock. But they can also be caused more rapidly, as was the case when officials in Fort Myers discovered a large sinkhole under a public sidewalk next to a popular beachside restaurant.
This sinkhole, which reports say was large enough to swallow two Volkswagens, had formed due to the loss of the seawall at the edge of the beach and, unlike some sinkhole damage, was easily confirmed as sinkhole activity. Inspectors discovered that a thin layer of concrete was all that remained to support the people walking overhead, after the underlying earth had been washed away by the tide and water currents. Below the sidewalk was an 18-foot drop into the hole, now filled with seawater.
The neighboring restaurant, aptly called Nervous Nellie's, had to close its patio for more than a month while crews worked to fix the seawall and fill in the sinkhole. City officials believe a county pipeline project from five years ago is to blame, when the contractor ran a pipeline under the seawall but caused it to shift and allow water to penetrate under the sidewalk.
While Florida sinkholes generally form over hundreds or thousands of years, as this incident demonstrates, sinkholes can also be formed by man-made events. Other actions which can trigger sinkholes include land development, changing natural water flow routes and heavy pumping of groundwater. This case also demonstrates that sinkholes can go undetected even in high-traffic areas and can affect commercial buildings as well as personal or private residences.
Geologists use the term "subsidence incident" to describe any loss of earth that may look like a sinkhole, but may have developed in some way other than the slow erosion of the underlying bedrock. Thus the incident on Fort Myers Beach may not technically be a sinkhole. But regardless of what it is called, the problems that result are the same-increased costs to the landowner, and the risk of harm to anyone passing by.
If you've been affected by a sinkhole, talk with an attorney who is familiar with both Florida's unique geology and with the Florida sinkhole laws that protect your rights.
