A garbage truck became trapped in a sinkhole in the city of Hollywood in Broward County, Florida, on Friday 29 September 2017. Nobody was hurt in the incident, which occurred when the truck was attempting to reverse through a puddle, when the rear passenger side wheel became trapped in the hole.
Garbage truck trapped in a sinkhole in Hollywood, Florida, on 29 September 2017. ABC Local News 10.
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.
The approximate location of the 29 September 2017 Hollywood Sinkhole. Google Maps.
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.
However on this occasion the sinkhole is believed to have been caused by a burst water main, that washed out soft sediments beneath the road. The incident has also left houses in the immediate area, and caused a drop in water pressure across the wider Hollywood area. Since this drop in pressure can effect the efficiency of water treatment plants, residents of the city are being advised to boil water before consumption until further notice.
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