Florida has the most sinkholes in the nation.

Sinkholes can form anywhere in Florida, but the highest activity level occurs in west central Florida because of the karst limestone environment. There are several influences that increase the risk of sinkhole activity such as long-term weather conditions, heavy acidic rains, and drought-like conditions.

The regional map below depicts sinkhole locations that have been reported since 1954 by the Florida Geological Survey Series. It does not show all sinkhole activity in Florida but shows a generalization of how widespread this problem is.

• Zone 1 (Yellow): This region consists of exposed or thinly-covered carbonate rocks. Broad and shallow sinkholes are common in this area. Cities in the zone 1 region include Miami, Coral Springs, Hialeah, and Hollywood.
• Zone 2 (Green): This region has permeable sand that varies in thickness from 20 to 200 feet. It mainly consists of small cover subsidence. Zone 2 cities include Fort Lauderdale, Port St. Lucie, and Orlando.
• Zone 3 (Blue): This region has cohesive, low-permeable soil that forms abrupt collapse sinkholes. Cities in zone 3 include Tampa, Tallahassee, and St. Petersburg.
• Zone 4 (Pink): This region consists of deeply inter-bedded carbonate rocks and cohesive clayey sands. Sinkholes are uncommon in this region, but collapse and small subsidence sinkholes can occur in shallow beds. Cities located in zone 4 include Jacksonville and St. Augustine.

Sinkhole formation has accelerated over the years. They are commonly created by extended droughts, heavy rainfall, land development, water pumping, and construction of retention ponds. Sinkholes in Florida can range in size small to large. Some are large enough to swallow homes, roads, swimming pools, and buildings.

Not only does sinkhole activity destroy structures, but they also pose an environmental concern. The carbonate rocks, which are present in sinkhole formation, provide direct access to all types of pollutants such as fertilizers and pesticides. Oil and gasoline also channel directly into the sinkhole. Despite all the problems sinkholes produce, they are a natural part of the ecosystem.

Typically, sinkholes are no more than a headache for property owners, but when tragedy does strike, it’s the stuff of nightmares. Among the six recorded deaths from sinkholes in Florida history is Jeffrey Bush, who was sleeping in his bedroom when a sinkhole sucked him 20 feet underground. His body was never recovered.