You've probably never been worried about sinkholes – here's why you should be

Independent

23-02-2025

Sinkholes are no longer rare – it's time to ask what's making them worse. For most of us, sinkholes are the stuff of science fiction movies – terrifying, but rare. That illusion collapsed this week in Godstone, Surrey, when two five-metre-deep holes suddenly opened up in a residential street, forcing the evacuation of 30 homes.
Experts suspect a water main burst beneath the road and eroded the soil, in combination with the fact that the region's underground soils were once the home to the town's sand quarry. Dr Philip Collins, deputy dean of the College of Engineering at Brunel University of London, explained quite simply that the underlying sand likely became very 'weak when it becomes wet' and that, combined with some clay-rich layers in the Godstone sand, that likely would 'heave and shrink over time'.
The reason behind the formation then may be very localised. But as scientists investigate, the incident serves as a reminder that sudden ground collapses are not as rare now as they once seemed. Around the world, sinkholes are appearing more frequently, and there is a budding understanding of how climate change might be driving these formations, with changing rainfall conditions, both when the underlying soil is too wet and too dry.
In January 2021, a sinkhole in Naples swallowed a hospital car park, causing power outages and temporary disruptions at the Ospedale del Mare, which had a Covid-19 recovery unit. In 2022, sinkholes swallowed roads and farmland in parts of China, including Guangxi and Hunan. Scientists have linked increasing sinkhole activity in some regions to changing rainfall patterns and groundwater depletion. In May 2023, a long-dormant sinkhole in Daisetta, Texas, first formed in 2008, suddenly expanded overnight by 150 feet, raising concerns for nearby homes and infrastructure.
From Europe to the US and Asia, sinkholes are appearing in new areas, and this seems to be happening with greater frequency, as extreme weather and human activity make the ground more unstable.
Sinkholes happen when underground layers of soil or rock weaken and collapse, often due to shifts in water levels. Picture a sponge drying out and shrinking, then suddenly being soaked with water. It softens, buckles, and caves in. Climate change is intensifying both extremes – droughts that deplete underground reservoirs and storms that overwhelm the land with too much water too quickly.
In north-eastern Spain, researchers found a consistent link between sinkholes and drought periods. When underground aquifers dry up, air pockets replace the missing water, leaving the surface fragile. The next heavy rain, instead of replenishing the ground, saturates the weakened soil and triggers collapses.
A similar pattern has been observed in Florida, where hurricanes bring record-breaking rainfall after months of dry conditions, causing land to crumble weeks after the storm has passed. Following Hurricane Ian in 2022, sinkholes began appearing across central Florida, swallowing roads and backyards long after the floodwaters had receded.
Unlike hurricanes or wildfires, sinkholes do not come with forecasts or evacuation warnings. We can't monitor them like we do the weather. For the most part, like they did this week, they open without notice. This makes them extremely dangerous in urban areas where underground infrastructure and ageing roads combine with a drought or over-extraction of underground water. And after this week, they now take up way too much rent-free space in my head.
The financial cost of these disasters is rising as well. In the US, sinkhole-related damage now exceeds $300 million annually. In China's Shaanxi province, more than 20,000 sinkholes were recorded between 2000 and 2020, a number that continues to grow as rainfall patterns shift. In the Middle East, excessive groundwater extraction has led to increased sinkhole activity in Iran, Jordan, and the Dead Sea region, where over 6,000 sinkholes have formed due to falling water levels.
This is part of what climate change looks like. It might not be the part you thought to expect and may not have directly contributed to this week's sinkholes in Godstone, but it is increasingly part of the patchwork of climatic uncertainty. We are not just at risk from heatwaves and melting ice caps, but changes in rainfall patterns literally seep into the soil and make the very ground we walk on increasingly unstable.
Although there are multi-input efforts to model and improve geological stability around the world, it's still very hard to predict or prevent sinkholes from forming. We can, however, start treating them as a symptom made potentially worse and far more common by our much larger addiction to burning fossil fuels and our general neglect of the uniquely changing Earth around us, both above our heads and below our feet.