Around 11.00 pm local time on Thursday 27 February 2013, the family of Florida man Jeff Bush heard a loud crash followed by screaming from his bedroom, in Faithway Drive, Seffner near Tampa. His brother, Jeremy, rushed into the room to find the a mattress disappearing into a hole in the floor and nor sign of Mr Bush. Jeremy leapt into the hole, which was continuing to grow, but was unable to find his brother, who is now missing presumed dead. Several nearby houses have now been cordoned off, while Hillsborough County Fire Rescue attempt to locate Mr Bush and determine how far the hole will spread.
Deputies from the Hillsborough County Sheriff's Office setting up a cordon around homes affected by the sinkhole. Reuters/Brian Blanco.
Southwest Florida is particularly prone to sinkholes, thought the Seffner Sinkhole is considered exceptional, due to the porous limestone that underlies much of the area. 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.
Graphic showing the processes by which sinkholes can form in southern Florida. Southwest Florida Water Management District.
See also To cull or not to cull? The Goliath Grouper in Floridan waters, Massive sinkhole opens up in Assumption Parish, Louisiana.
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