Gwynedd, Porthmadog
LL49 9AE in Porthmadog has a Low flood risk. Heat risk is Lower, with a median (50th percentile) of 8 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 Low at PM2.5 4.3 μg/m³, within 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 GeoClimate).
Flood risk at LL49 9AE is rated Low, based on Natural Resources Wales flood mapping.
Natural Resources Wales flood zone data shows low flood risk for LL49 9AE in Porthmadog. The band reflects the highest flood risk within the postcode; some properties within this postcode may face little or no direct flood risk. For a specific property, a conveyancing search will confirm the exact flood zone position.
Air quality at LL49 9AE is rated Low, 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.
British Geological Survey data classes the underlying soil at LL49 9AE as Quaternary Marine/Estuarine Sand And Silt, with shrink-swell hazard rated improbable (subsidence risk band: Low). A structural survey is the reliable way to assess ground conditions for a specific property.
The nearest projected coastal erosion zone to LL49 9AE is 51 m away (NRW NCERM No Active Intervention - Medium-term (2025-2055) mapping) and the postcode is in the 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 LL49 9AE draws on four official UK open data sources: Natural Resources Wales flood mapping, Met Office UKCP18 climate projections, Defra UK-AIR PM2.5 monitoring, and British Geological Survey GeoClimate subsidence mapping. Risk ratings are a screening tool, complementing - not replacing - the searches and surveys ordered as part of a property transaction. Data covers Gwynedd and is updated as new official datasets are published.
Gwynedd has a predominantly upland and coastal setting with mountains, river valleys and dispersed settlements and experiences cool, wet winters and mild summers, shaped by Atlantic weather and steep catchments.
Practical check: The nearest projected erosion zone is 51m 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 LL49 9AA is at localrisk.co.uk/postcode/LL499AA, and you can compare LL49 9AE side by side with any UK postcode at localrisk.co.uk/compare.