Lewes, Seaford (BN25)
BN25 1AL in Seaford (BN25) has a Medium flood risk - EA NaFRA2 data records 11 properties in a flood risk zone. Heat risk is Lower, with a median (50th percentile) of 25 days above 25°C per year, averaged over the 2021-2040 period under the RCP8.5 high emissions scenario (Met Office UKCP18). Air quality is Medium at PM2.5 6.3 μg/m³, above the WHO annual guideline of 5 μg/m³ (Defra UK-AIR). Ground conditions are Low risk, with Fluvial Clays, Silts Sands And Gravel geology; shrink-swell risk is classed as improbable (BGS GeoSure).
Flood risk at BN25 1AL is rated Medium, based on Environment Agency NaFRA2 modelling.
Environment Agency flood zone data places BN25 1AL in the medium flood risk band. EA NaFRA2 data shows 3 at medium risk, 8 at low risk in this postcode. The band reflects the highest flood risk within the postcode; some properties within this postcode may face little or no direct flood risk. Individual properties within BN25 1AL can differ - a formal flood risk search is recommended before any property transaction.
Air quality at BN25 1AL is rated Medium, based on Defra UK-AIR annual mean PM2.5 data. Fine particulate matter (PM2.5) comes primarily from road traffic, industry, and domestic burning. Long-term exposure above the WHO guideline of 5 µg/m³ is linked to respiratory and cardiovascular health risks. Buyers and renters in higher air quality risk areas may wish to consider whether the property is near busy roads or industrial sources.
BGS GeoSure data classes the underlying soil at BN25 1AL as Fluvial Clays, Silts Sands And Gravel, with shrink-swell hazard rated improbable (subsidence risk band: Low). Soil type and shrink-swell behaviour drive subsidence claims following dry summers; recent ABI data shows insurer payouts rose sharply after the 2022 and 2025 hot summers. A structural survey is the reliable way to assess ground risk for a specific property.
This LocalRisk report for BN25 1AL draws on four official UK open data sources: Environment Agency NaFRA2 flood modelling, Met Office UKCP18 climate projections, Defra UK-AIR PM2.5 monitoring, and British Geological Survey GeoSure subsidence mapping. Risk ratings are a screening tool, complementing - not replacing - the searches and surveys ordered as part of a property transaction. Data covers Lewes and is updated as new official datasets are published.
Lewes has a river-valley and downland setting with a historic town centre and surrounding countryside and experiences cool, wet winters and warm summers, shaped by South Downs topography and drainage patterns.
Practical check: EA data flags 11 properties at flood risk here - check whether the property is among them by comparing its position to the flood zone boundary. With 25 hot days projected (UKCP18 50th percentile, 2021-2040 average under RCP8.5), note which bedrooms face west (hottest in evening) and whether windows allow through-ventilation. These are postcode-level indicators - conditions vary between individual properties.
Climate risk can change street by street, so it is worth checking neighbouring postcodes too. The full risk report for BN25 1AA is at localrisk.co.uk/postcode/BN251AA, and you can compare BN25 1AL side by side with any UK postcode at localrisk.co.uk/compare.