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Does Hersham flood?

Surrey
38postcodes in the EA rivers-and-sea dataset
12river gauges within 10 km
8years with a mapped flood record within 5 km
🏠 Thinking of buying in Hersham? Get the detailed Property Flood-Risk Report for any Hersham postcode — official risk band, recorded floods since 1703, warning history, river behaviour and nearby storm overflows. £19 one-off, instant. Learn more →

What the Environment Agency's rivers-and-sea flood-risk data says about Hersham

Ordnance Survey places 38 postcodes in Hersham in the Environment Agency's rivers-and-sea flood-risk dataset (Risk of Flooding from Rivers and Sea). Each postcode is counted once, under the worst band any of its properties reaches; together they hold 480 properties in the EA dataset's likelihood bands.

EA likelihood bandPostcodes (worst band)Properties in the EA datasetof which homes
High000
Medium000
Low31356347
Very low7124121
All bands38480468

This dataset covers flooding from rivers and the sea only — one of five flood sources. Surface water, groundwater, sewers and reservoirs are assessed separately, so a postcode missing from it is not proof that a place cannot flood. The band describes the land around properties (allowing for defences), not any single address and not today's conditions.

Rivers and live river levels near Hersham

Environment Agency gauges within 10 km of Hersham watch River Mole, River Thames, River Wey, Addlestone Bourne, Hogsmill River.

Distances are from the middle of Hersham's at-risk postcodes. Tidal and structure gauges are shown as readings only — the tide and sluice gates move them, not floods. A gauge with no recent reading shows no level.

The watercourse nearest Hersham

The nearest watercourse on the river map is the River Mole, about 190 m from the middle of Hersham's at-risk postcodes. It flows into the River Ember about 3.0 km downstream.

A gauge downstream shows water that has already passed this point; one upstream sees it first. Distances along the river are from the point on the River Mole nearest the middle of Hersham's at-risk postcodes. From Ordnance Survey’s river map (OS Open Rivers), which leaves out small streams, ditches and culverts, so a nearer one may exist. This describes where water goes on the map; it says nothing about flooding at any address. Contains OS data © Crown copyright and database rights 2026.

Flood warning areas near Hersham

50 Environment Agency flood warning areas lie within 10 km of Hersham. The EA has issued 533 flood warnings and alerts for them since 2006, most recently on 8 Oct 2026.

Recorded floods near Hersham

Floods whose mapped extent (EA Recorded Flood Outlines) reached within ~5 km of Hersham, most recent first. Records, not floods: no outline on the record is not evidence a place has not flooded. See them on the map →

…and 1 earlier recorded flood on the map.

Rainfall near Hersham

Hersham gets about 663 mm of rain a year on average (wettest month November, 73 mm; driest March, 42 mm). That is 43% drier than the UK as a whole, which averages 1,163 mm a year. Source: Met Office HadUK-Grid 1991–2020 (5 km grid), 2.3 km from the place centre.

The nearest rain gauge, Rainfall station (7.6 km away), recorded 2.6 mm in the last 24 hours and 73.9 mm in the last 7 days (latest reading 33 min ago).

At-risk postcodes in Hersham

Every postcode Ordnance Survey places in Hersham that appears in the EA's rivers-and-sea dataset, worst band first. Each links to its own flood-risk page.

Low likelihood (31)

KT12 4BUKT12 4BYKT12 4EPKT12 4LEKT12 4LFKT12 4LGKT12 4LHKT12 4LLKT12 4LNKT12 4LPKT12 4LQKT12 4LRKT12 4LWKT12 4NQKT12 4NYKT12 4PEKT12 4PFKT12 4PHKT12 4PJKT12 4PLKT12 4PNKT12 4PPKT12 4PWKT12 4QJKT12 4QUKT12 4QXKT12 4QZKT12 4RAKT12 4RBKT12 4SGKT12 4SQ

Very low likelihood (7)

KT12 4HQKT12 4LXKT12 4LYKT12 4NBKT12 4NDKT12 4NEKT12 4NG

Postcode districts

KT12 · 38

Sources

FloodRadar summarises public flood data. It is not a flood-risk survey of any property, and it does not replace official GOV.UK flood warnings or the GOV.UK long-term flood risk service.

Flood-risk bands: © 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.

Recorded Flood Outlines, flood warning areas and warning history © Environment Agency copyright and/or database right 2025. Licensed under the Open Government Licence v3.0.

River levels and rainfall: Environment Agency real-time flood-monitoring data, updated every 15 minutes (Open Government Licence v3.0).

Average rainfall: HadUK-Grid v1.3.2, Met Office. Contains public sector information licensed under the Open Government Licence v3.0.

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.

All data sources & licences