In February 2007, a very large, deep circular hole with vertical walls opened in a poor neighborhood in northeast Guatemala city, killing three people.
This hole, which is classified by geologists as either a “piping feature” or “piping pseudokarst”, was 100 metres (330 ft) deep, and apparently was created by fluid from a sewer eroding uncemented volcanic ash and other pyroclastic deposits underlying Guatemala City.As a result, one thousand people were evacuated from the area.The piping feature has since been mitigated and plans to develop on the site have been proposed. However, critics believe municipal authorities have neglected needed maintenance on the city’s aging sewerage system, and have speculated that more piping features are likely to develop unless action is taken.