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
Bayou Corne sinkhole of the damage it has caused, which sent former and current residents of the town into a frenzy as a heated debate ensued over whether the company believed to be responsible for severe damage and loss of homes should be given permission to tamper more with an area already considered to be "deeply contaminated," as environmental activist Nara Crowley stated. In July 2015, Texas Brine began a series of lawsuits against Occidental Petroleum, claiming that an oil well drilled by Occidental Petroleum in 1986 triggered the cavern wall break that led to the creation of the sinkhole. Texas Brine is