Porthtowan, Cornwall
Up to High likelihood
Properties in TR4 8AA sit in the Environment Agency's High flood-likelihood band (worst property). The band is the worst found in the postcode — it describes the land around properties (defence-adjusted, rivers & sea), not any single address, and not today's conditions.
| Likelihood band | Annual chance | Properties | Of which homes |
|---|---|---|---|
| High | greater than 3.3% | 8 | 5 |
| Medium | 1% – 3.3% | 1 | 1 |
| Low | 0.1% – 1% | 16 | 15 |
| Very low | below 0.1% | 0 | 0 |
Over a 25-year mortgage, a property in a high-likelihood area has at least a 57% chance of flooding at least once.
The ground here sits at about 15 m above sea level and falls 97 m across the surrounding 800 m. Surface water reaching this point runs off ground lying to the east, 85.4 m higher.
Because properties in the high likelihood band; 10 official warnings since 2006.
The map above shows the real EA rivers & sea likelihood cells around TR4 8AA. The small panels are illustrative previews of the report's per-layer map views — the full report draws each layer for real, plus recorded extents, defences and a building picker on an interactive map.
Warnings cover flood areas, not individual addresses.
Imogen (2016, 4 warnings nearby) · Chandra (2026, 1 warnings nearby)
| Gauge | River | Distance | Typical high | Highest on record |
|---|---|---|---|---|
| Rose in Vale | Perrancombe Stream | 6.0 km | 1.20 m | 1.10 m |
| Perrancoombe | Perrancombe Stream | 8.5 km | 1.00 m | 0.94 m |
| Bolingey Cocks Bridge | Bolingey Stream | 9.1 km | 1.09 m | 1.53 m |
| Bissoe | Carnon River | 10.3 km | 0.86 m | 1.45 m |
Live levels, predictions and rain-response behaviour are on each gauge's page and in the property report.
| Overflow | Discharges into | Distance | Spills | Hours |
|---|---|---|---|---|
| Echo Corner Pscso/eo | Porthtowan Stream (s) | 0.3 km | 44 (2024) | 646 |
| Echo Corner Pscso/eo | River Kenwyn | 0.4 km | 0 (2024) | 0 |
| Bridge Ps / Cso / Eo | Atlantic Ocean (c) | 3.6 km | 142 (2024) | 2,669 |
| Peterville Pumping Station | Trevaunance Stream(s) | 4.2 km | 50 (2024) | 383 |
Official annual EDM figures — a water-quality signal for local watercourses, not a property flood-risk factor.
No mapped flood-defence assets within 500 m of the postcode centre. Defences reduce risk, never remove it.
The interactive flood-risk map with a building picker (your exact house, not the postcode), the 2050s climate view, surface-water and planning flood zones at your building, exact recorded-flood distances, year-by-year warning charts, watercourses including culverted streams, an insurance outlook with the Flood Re rules, and a printable document with every dataset receipt — start with the free preview, unlock for £19.
At-risk postcodes near TR4 8AA — all in the TR4 district.
© Environment Agency copyright and/or database right 2025. All rights reserved. Some features of this map are based on digital spatial data from the Centre for Ecology & Hydrology, © NERC (CEH). © Crown Copyright and Database Rights 2025 OS AC0000807064. This product is produced in part from PAF® and Multiple Residence Data, the copyright in which is owned by Royal Mail Group Limited and/or Royal Mail Group plc. All rights reserved. Licence number AC0000807064. Place names: Contains OS data © Crown copyright and database rights 2026. Contains Royal Mail data © Royal Mail copyright and database right 2026. Contains National Statistics data © Crown copyright and database right 2026. Licensed under the Open Government Licence v3.0. Recorded Flood Outlines and warning history © Environment Agency copyright and/or database right 2025. Storm-overflow figures: EA Event Duration Monitoring. Flood defences © Environment Agency (OGL v3). This page summarises public area-level data — it is not a flood-risk survey and not a substitute for the official GOV.UK service. All data sources & licences. More postcodes: the TR4 district.