This shapefile is a based on the 17" x 21" paper Map titled "Sinkhole Type, Development and Distribution in Florida" also known as Map Series 110 and published 1985 by United States Geological Survey in cooperation with the Florida Department of Environmental Regulation, Bureau of Water Resources Management and Florida Department of Natural Resources, Bureau of Geology

The FGS used a modeling technique called Weights of Evidence (WofE) that involves the combination of diverse spatial data to describe and analyze interactions and generate predictive models from which a map of favorability can be produced. The project began with a one year pilot study in Columbia, Hamilton, and Suwannee Counties, during which methodologies were developed in preparation to model the entire state. To train and validate the model, locations of sinkholes were required. Over two-and-a-half-years, field teams traversed the state investigating over 3,600 points of interest (potential sinkholes) and mapped 654 sinkholes. After evaluating fourteen different spatial data types, the three statistically strong spatial data layers were used to model the favorability of the State’s geology to sinkhole formation. The resulting map depicts four classes representing areas where the geology is least favorable to most favorable to sinkhole formation.

What is a Subsidence Incident? 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 subterranean events can cause holes, depressions or subsidence of the land surface that may mimic sinkhole activity. These include subsurface expansive clay or organic layers which compress as water is removed, collapsed or broken sewer and drain pipes or broken septic tanks, improperly compacted soil after excavation work, and even 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. For more information - https://floridadep.gov/fgs/sinkholes/content/subsidence-incident-reports

The U.S. Geological Survey, in cooperation with the University of South Florida and Eckerd College, completed a bathymetric, sidescan sonar, high-resolution seismic-reflection, and surface sediment sampling survey of the inner shelf environment along the western Florida coast. The survey area extends 15km from Sarasota Point to Buttonwood Harbor. This study is part of a larger program initiated by the U.S. Geological Survey to map the geologic framework and monitor the modern processes that affect the western Florida coastal zone. This portion of the project included a reconnaissance high-resolution seismic and side-scan sonar surveys of the entire study area, detailed mapping to identify patterns of hard grounds and sediment cover, and coring of sediments to document historical development of the inner shelf and coastal system.

Map Direct focus to show Subsidence Incident Reports. Please refer to https://floridadep.gov/fgs/sinkholes for more information. Originally created 02/04/2011, and moved to Map Direct Lite on 03/17/2015 Please contact GIS.Librarian@floridadep.gov for more information.

Sinkhole Insurance Market Outlook

According to the latest research conducted in 2025, the global sinkhole insurance market size stands at USD 3.2 billion in 2024, reflecting a robust demand across both developed and emerging economies. The market is expected to register a CAGR of 6.9% from 2025 to 2033, reaching an estimated USD 6.3 billion by the end of the forecast period. This significant growth trajectory is primarily driven by increasing awareness of natural disaster risks, rising property values, and a growing need for comprehensive risk mitigation solutions among property owners worldwide.

One of the primary growth factors fueling the sinkhole insurance market is the increasing frequency and severity of sinkhole occurrences linked to climate change and urban expansion. As urbanization accelerates and more land is developed for residential, commercial, and industrial purposes, the risk of ground subsidence and sinkhole formation rises, especially in regions with soluble rock formations such as limestone. This has prompted both individuals and businesses to seek specialized insurance products to protect their assets from potentially catastrophic losses. Furthermore, advancements in geotechnical assessment and risk modeling have enabled insurers to better price and tailor sinkhole insurance products, making them more accessible and relevant to a broader range of customers.

Another important driver is the evolving regulatory landscape and the increasing involvement of government agencies in mandating or recommending sinkhole coverage in high-risk zones. Several states in the United States, for instance, have introduced regulations requiring insurers to offer sinkhole coverage as part of property insurance packages or as optional endorsements. This regulatory push, combined with public awareness campaigns and educational initiatives, has led to a surge in policy uptake, particularly in regions historically affected by sinkhole events. Additionally, the growing integration of advanced technologies such as satellite imagery and ground-penetrating radar has enhanced risk assessment capabilities, resulting in more accurate underwriting and claims processing.

The proliferation of digital distribution channels and the rise of insurtech platforms have also played a pivotal role in expanding the sinkhole insurance market. Online platforms and digital brokers have simplified the process of comparing, purchasing, and managing insurance policies, thereby attracting a tech-savvy demographic and increasing market penetration. The ongoing digital transformation within the insurance sector has further enabled insurers to offer personalized products and improve customer engagement, driving sustained growth in the sinkhole insurance market.

Regionally, North America dominates the global sinkhole insurance market, accounting for the largest share in 2024, followed by Europe and Asia Pacific. The high prevalence of sinkhole-prone areas in the United States, particularly in states like Florida, Pennsylvania, and Tennessee, has made North America a focal point for both product innovation and regulatory activity. Meanwhile, Europe and Asia Pacific are witnessing steady growth, driven by increasing urban development, improved risk awareness, and the gradual adoption of specialized insurance solutions. Latin America and the Middle East & Africa, while still emerging markets, are expected to register notable growth rates over the forecast period as infrastructure development and insurance penetration continue to rise.

Coverage Type Analysis

The sinkhole insurance market, when segmented by coverage type, includes Structural Coverage, Contents Coverage, Additional Living Expenses, and Others. Structural coverage remains the most sought-after segment, as it directly addresses the primary concern of property owners: the risk of structural damage or collapse due to sinkhole activity. This coverage typically encompasses repairs to the foundation, walls, and other integral components of buildings, ensuring that policyholders are protected against significant financial losses. The increasing incidence of severe sinkhole events, particularly in urban and suburban areas, has heightened demand for comprehensive structural coverage, prompting insurers to refine their product offerings and underwriting criteria.

Contents coverage, which protects personal belongings and valuable assets within a property, has seen rising interest, es