Smallfield, Surrey
Up to High likelihood
Properties in RH6 9NR 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% | 1 | 0 |
| Medium | 1% – 3.3% | 0 | 0 |
| Low | 0.1% – 1% | 2 | 2 |
| 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.
RH6 9NR gets about 797 mm of rain a year on average (wettest month November, 93 mm; driest March, 49 mm). That is 31% drier than the UK as a whole, which averages 1,163 mm a year.
A thirty-year average for the surrounding area, not a measurement at this address and not a flood risk on its own: a dry area floods when a storm sits over it, and a wet one may drain away perfectly well. Source: Met Office HadUK-Grid 1991–2020 (5 km grid), 1.2 km away. Average rainfall: HadUK-Grid v1.3.2, Met Office. Contains public sector information licensed under the Open Government Licence v3.0.
The ground here sits at about 59 m above sea level and falls 9 m across the surrounding 800 m. Surface water reaching this point runs off ground lying to the north-north-east, 1.8 m higher.
The river map has no watercourse within 1 km of the centre of RH6 9NR.
That means this spot is not on the river map, not that there is no water here: Ordnance Survey’s river map (OS Open Rivers) leaves out small streams, ditches and culverts. Contains OS data © Crown copyright and database rights 2026.
Because properties in the high likelihood band; 3 recorded flood outlines mapped nearby; 184 official warnings since 2006.
The map above shows the real EA rivers & sea likelihood cells around RH6 9NR. 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.
| Date | Mapped flood extent | Approx. distance |
|---|---|---|
| Dec 2013 | Smallfield_Dec2013 | ~0.3 km |
| Nov 1974 | 06NovemberAutumn1974 | ~1.2 km |
| Sep 1968 | 06SeptemberAutumn1968 | ~1.0 km |
These are extents the Environment Agency has mapped, not a list of every flood. Records, not floods: no outline on the record is not evidence a place has not flooded. The full report tests whether any extent covered the exact spot.
2013-14 UK winter floods (2013, 32 warnings nearby) ▶ replay it here · Dennis (2020, 4 warnings nearby) ▶ replay it here · Henk (2024, 4 warnings nearby) ▶ replay it here · Erik (2019, 3 warnings nearby) ▶ replay it here
| Gauge | River | Distance | Typical high | Highest on record |
|---|---|---|---|---|
| Peeks Brook Lane | Burstow Stream | 2.1 km | 2.65 m | 2.90 m |
| Bonehurst Bridge | Burstow Stream | 3.7 km | 3.70 m | 4.47 m |
| Gatwick Link | Gatwick Stream | 3.8 km | 1.60 m | 2.17 m |
| Horley | River Mole | 4.9 km | 2.42 m | 3.44 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 |
|---|---|---|---|---|
| Burstow Wastewater Treatment Works | Burstow Stream | 1.6 km | 133 (2024) | 1,758 |
| Crawley No. 2 Wwtw | Tributary Of Gatwick Stream | 4.3 km | 46 (2024) | 533 |
| Domewood Pumping Station | Freshwater River | 4.5 km | 35 (2024) | 391 |
Official annual EDM figures — a water-quality signal for local watercourses, not a property flood-risk factor.
2 mapped flood-defence assets within 500 m — nearest ~254 m (natural high ground). 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 RH6 9NR — all in the RH6 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 (England); live overflow status © the water companies, incl. Dŵr Cymru Welsh Water and Scottish Water. 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 RH6 district.