Florida Geological Survey - Data and Maps
Subsidence Incident Reports
Sinkholes are closed depressions in areas underlain by soluble rock such as limestone, dolostone, gypsum, or salt. Sinkholes form when
surface sediments subside into underground voids created by the dissolving action of groundwater in the underlying bedrock.
Other events that can cause holes, depressions or subsidence of the land surface that may mimic sinkhole activity include:
- subsurface expansive clay or organic layers which compress as water is removed,
- collapsed or broken sewer and drain pipes;
broken septic tanks;
- improperly compacted soil after excavation work; and
- buried trash, logs and other debris.
Commonly, a reported depression is not verified by a Licensed Professional Geologist to be a true sinkhole, and the cause of subsidence
is not known. Such an event is called a subsidence incident. The Florida Geological Survey maintains and provides a
downloadable database of reported subsidence incidents statewide. While this data may include some true sinkholes, the majority of the
incidents have not been field-checked and the cause of subsidence is not verified.
There three different types of files:
- An Excel Spreadsheet,
- An ESRI ArcGIS compatible shapefile
- A kmz overlay file for use in Google Earth and similar mapping products.
These files provide subsidence incidents reported to the Florida Geological Survey and
updated through April, 2015.
After clicking on any of the Subsidence Incident Reports links you will be taken to a page where you must
submit your e-mail address: your e-mail address is used only to statistically track who is using the Subsidence
Incident Reports and will not be used in any other way. After submitting your e-mail address and before you can
download the Subsidence Incident Reports you will be asked to read and agree to a disclaimer.
A Word Document titled
"The FGS the FSRI, and Karst Data in Florida"has been provided here for anyone interest in the
history of the Database and other subsidence incident publications.
Please read the Read Me file
for further instruction
Contact Clint Kromhout
(email@example.com) with questions
- The Florida Geological Survey Arcview shapefile formats are projected using a DEP modified ALBERS projection. The ArcView
and ArcMap projection data is available at:
- For further assistance on GIS information available through the FGS please contact,
(firstname.lastname@example.org, ph. 850-617-0327)
May 11, 2015