Arun, North Bersted (PO21)
PO21 1XB in North Bersted (PO21) has a High flood risk - EA NaFRA2 data records 9 properties at high flood risk. 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 6.1 μg/m³, above the WHO annual guideline of 5 μg/m³ (Defra UK-AIR). Ground conditions are Low risk, with Quaternary Marine/Estuarine Sand And Silt geology; shrink-swell risk is classed as improbable (BGS GeoSure).
Flood risk at PO21 1XB is rated High, based on Environment Agency NaFRA2 modelling.
Environment Agency flood zone data places PO21 1XB in the high flood risk band. EA NaFRA2 data shows 9 at high risk, 15 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. A formal flood risk search and review of buildings insurance availability is recommended before any property transaction in this area.
Air quality at PO21 1XB 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 PO21 1XB as Quaternary Marine/Estuarine Sand And Silt, 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.
The nearest projected coastal erosion zone to PO21 1XB is 73 m away (Erosion projected by 2055 (no climate change uplift) - SMP policy: Hold The Line mapping) and the postcode is in the very high coastal erosion risk band. Coastal erosion risk varies along the shoreline depending on local geology, sea defences and Shoreline Management Plan policy. Check the Shoreline Management Plan for this stretch for the projections that apply to a specific property.
This LocalRisk report for PO21 1XB 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 Arun and is updated as new official datasets are published.
Arun has a low-lying coastal setting and experiences cool, damp winters and warm summers, influenced by the English Channel and flat coastal plains. The district splits between a rural interior and an urban coastal strip taking in Littlehampton and Bognor Regis.
Practical check: EA flags 24 properties at flood risk here, near the coast - compare the floor level to the highest recorded tide line and check for flood resilience measures. 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. The nearest projected erosion zone is 73m away - check the Shoreline Management Plan policy for this stretch and whether the property is within 100 years of the erosion line. 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 PO21 1AA is at localrisk.co.uk/postcode/PO211AA, and you can compare PO21 1XB side by side with any UK postcode at localrisk.co.uk/compare.