How to gauge flood risk before you buy or rent a seafront property

Rising sea levels, stronger storms and increased erosion are making life on the coast riskier and more unpredictable. For potential buyers or renters, particularly in the wake of another winter of storms and flooding, questions around whether to invest in coastal properties are more urgent now than ever. The desire to understand flood risk before committing to a seaside home is understandable, but assessing that risk isn’t always straightforward. Knowing how people perceive these risks, however, will help scientists better communicate such risks. We surveyed over 700 UK residents in a nationwide study to understand how access to flood prediction maps, which indicate the relative risk of flooding for areas based on factors like sea-level rise, storm surges, and local topography, affected their housing preferences. These maps are typically available through government websites and are often consulted during the home-buying process via online property listings or planning reports. The results were striking. Once people were shown flood risk maps, their preferences changed decisively – away from scenic seafront properties and towards locations that were inland and considered to be “safe”. However, while this change in preference seems rational, it reveals a deeper underlying problem: flood risk is not being communicated clearly or effectively in the UK. Many people in our study treated flood maps as if their predictions were absolute and misinterpreted areas at risk of flooding as being exposed to actual flooding. In reality, these maps are based on mathematical models with varying degrees of complexity and uncertainty. Some widely used models are simple and treat flooding as a result of land elevation alone. Others are more complex and attempt to simulate how floodwater spreads over land. Unsurprisingly, these models can produce conflicting results.