Sinkhole urban areas due to water main breaks or sewer collapses when old pipes give way. They can also occur from the overpumping and extraction of groundwater and subsurface fluids. Sinkholes can also form when natural water-drainage patterns are changed and new water-diversion systems are developed. Some sinkholes form when the land surface is changed, such as when industrial and runoff-storage ponds are created; the substantial weight of the new material can trigger a collapse of the roof of an existing void or cavity in the subsurface, resulting in development of a sinkhole. Sinkholes tend to occur in karst landscapes. Karst
2007 Guatemala City sinkhole on the city's aging sewerage system, and have speculated that more piping failures are likely to develop unless action is taken. Several rainstorms also contributed to the sinkhole's collapse, as stormwater percolated into the ground, further dissolving the rocks beneath Guatemala City. Citizens of Guatemala City near the sinkhole also reported hearing rumblings a few weeks before its collapse. The INSIVUMEH (Guatemala's seismology institute) had placed a seismic meter there before the disaster; a robotic camera system was supposed to enter the cavity, but the disaster occurred first. On February 23, 2007, the sinkhole collapsed, forming a very large, deep