A new study has found that 1.2 million buildings at risk of flooding in England currently aren’t included in any of the country’s flood defenses.
The research, provided by mapping service Ordnance Survey and Snowflake, an AI data cloud company, shows that two-thirds of the buildings identified are in some of England’s most economically vulnerable corners. Most of the properties are homes, and are at risk due to surface-water flooding rather than from rising rivers or sea levels, according to the report published on Wednesday.
“The model provides insights into how well areas and properties are protected and where to prioritize investment in critical flood defenses,” said Tim Chilton, managing geospatial consultant at Ordnance Survey.
In the first two months of 2026, several regions across the U.K. had already experienced the highest rainfall levels in more than a century, underscoring the growing urgency of addressing flood risk. In England, there are 6.3 million properties in areas at risk of flooding from surface water, coastal swells and overflowing rivers, the government’s Environment Agency has previously estimated.
At the same time, more properties are being built on flood-prone land, with the insurer Aviva estimating back in February that roughly 11% of new homes built between 2022 and 2024 are in areas facing medium to high flood risks, compared to 8% over the previous decade.
The analysis, which was carried out using an AI model combining building data with flood risk management plans, suggests that the combination of increasingly heavy rainfall and the spread of paved, urbanized areas is proving particularly dangerous. The risks are exacerbated by the fact that insurance is getting harder to access, while the head of the state-backed Flood Re program recently warned that poorer households often get left behind.
A spokesperson for the UK government’s Department for Environment Food and Rural Affairs said it was spending £10.5 billion ($14.2 billion) on defending infrastructure and homes from flooding, in an emailed comment. And separately on Wednesday, the U.K. Environment Agency said it had improved flood protections for almost 62,000 homes over the past two years, 10,000 more than it had previously targeted.
The east coast of Yorkshire in the north of England has among the highest concentration of properties deemed at risk, according to the analysis. Buildings constructed before 2001, when legislation required that flood risk be factored into planning permissions, account for 84% of those at risk.
Top photo: A house is affected by flooding in Weycroft, on Jan. 27. Bloomberg.
Copyright 2026 Bloomberg.
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