Residents of Godstone in Surrey have been evacuated after two large sinkholes appeared on their high street, sparking fears of a gas explosion. But what causes these mysterious holes and can they be prevented?
Sinkholes form when the underlying rock collapses or is eroded by acidic rainfall, groundwater, or flowing water. In Britain, they are typically 5-10 meters deep but can reach up to 50 meters.
Heavy rain, surface flooding, and drought can trigger sinkholes by destabilizing underground cavities. Mining, burst water mains, and construction work can also be a factor. Areas with certain types of rock, such as limestone and clay, are more prone to sinkholes.
Godstone sits on weakly cemented sands that are prone to erosion and flushing by running water. The area’s history of sand mines could have contributed to the recent sinkhole formation. Geologists believe it may be due to a burst water main or the collapse of an old mine shaft.
While the exact cause is unknown, experts say that climate change and more extreme weather events are likely to increase sinkhole formation. Ensuring sufficient drainage in vulnerable areas can help prevent these disasters.
Source: https://www.theguardian.com/world/2025/feb/20/what-are-sinkholes-how-are-they-formed-and-why-did-one-appear-in-a-surrey-street