Six families have been forced to evacuate their homes after a sinkhole opened behind the properties in the West End Estates neighbourhood of Gainsville, Florida. The hole first appeared on Thursday 15 October 2020, and has now expanded to be about 15 m across and about 10 m deep, with whole trees falling into it and concerns the gas mains and other utilities may be affected. Families living close to the hole were asked to leave their homes by local officials on Thursday 22 October, but have expressed concern as there appears to be no clear plan as to whether they will be able to return to their homes in the future, or if they will be compensated if they cannot.
Sinkholes are generally caused by water eroding soft limestone or unconsolidated deposits from beneath, causing a hole that works its way upwards and eventually opening spectacularly at the surface. Where there are unconsolidated deposits at the surface they can infill from the sides, apparently swallowing objects at the surface, including people, without trace.
Many parts of Florida are particularly prone to sinkholes, due to the porous limestone that underlies much of the state. This is eroded over time by acid in rainwater (most rainwater is slightly acidic, though pollution can make this worse), and can collapse suddenly, causing overlying sediments to collapse into the hole and a sinkhole to open up. This can be triggered by human activity, such as pumping water out (which causes the water to flow, facilitating acid dissolution of the limestone), but is essentially a natural process.
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