Two apartment blocks have been evacuated after a sinkhole opened close to them in the city of Ephrata in Lancaster County, Pennsylvania, on Tuesday 8 November 2016. The hole was initially reported as a small pothole at about 5.00 pm local time, but rapidly grew to be about 15 m wide and about 6 m deep, triggering the evacuations of the nearby apartments. A total of 19 residents of 12 apartments are said to have been effected, some of whom are believed to be elderly.
The site of the November 2016 Ephrata sinkhole. Ephrata Police Department.
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.
In this case the sinkhole is thought to have been caused by a burst water main, which washed away lose sediments beneath the road, undermining the structure and causing the surface to collapse. Around 1 136 000 litres of water are thought to have been lost due to this event, which will have cost the borough about US$900, though the cost of the repairs is likely to be far higher possibly exceeding US$1 million.
Follow Sciency Thoughts on Facebook.