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London Road, Staines - view towards the town centrePhoto: Stefan Czapski · CC BY-SA 2.0
D−Hazard risk Grade
Flood & hazards in Staines-upon-Thames · Environment Agency

More of Staines-upon-Thames’s homes are at high or medium flood risk than in 98% of UK towns: 24%, from rivers or the sea

On the Environment Agency’s maps, which allow for flood defences, “high or medium” means at least a 1 in 100 chance of flooding from rivers or the sea in any year. Staines-upon-Thames grades D− for hazard risk: #60 of 65 in Surrey.

1947worst recorded flood30flood warnings since 200640%at low risk
In brief

What stands out about Staines-upon-Thames’s hazards

From the Environment Agency’s maps and records and the BGS radon atlas, below.

A river town24% of homes are at high or medium risk from rivers or the sea, more than 98% of UK towns.Remembers 1947Floodwater covered 418 hectares of today’s Staines-upon-Thames in 1947; 4,737 of today’s households live inside past flood outlines.30 flood warnings since 2006For the parts of Staines-upon-Thames the Environment Agency warns directly; the most recent on 7 January 2024.Low radonEvery 1 km square over Staines-upon-Thames is in the lowest radon band: under 1% of homes above the action level.
By hazard

What Staines-upon-Thames faces

Each hazard against its own yardstick; meters run from low to high on that yardstick.

Rivers and the sea

24%of homes at high or medium risk
More than the typical UK town · more than 98% of towns
2,356 homes by the EA’s own count

Surface water

1.5%of homes at high or medium risk
More than 16% of UK towns
Rivers and sea: 24%

Past floods

12years with a recorded flood
Last recorded: January 2024
4,737 households inside past outlines

The River Thames

0.61 mhighest in winter 2025–26 at Penton Hook
10th-highest of 30 winters
Record 1.40 m, February 2014

Flood warnings

30flood warnings since 2006
168 flood alerts for the wider area
Last warning 7 January 2024

Radon

0%of the town in a radon Affected Area
Highest band here: Under 1% of homes
No square of 5% or more
Not on this page: coastal erosion, subsidence and shrink-swell ground (the British Geological Survey licenses it), groundwater flooding and reservoir failure.
Hazard risk Grade

Staines-upon-Thames grades D− for hazard risk

Flood risk from rivers and the sea, against all UK towns.

Homes at high or medium flood risk (24%)Fewer than 2% of UK towns

The share of homes at high or medium risk from rivers and the sea, ranked against every UK town of 1,000 or more: fewer homes at risk is better. Towns with none at high or medium risk are ordered by their share at low risk, so they don’t all share one score. Surface water and radon aren’t graded: they are described below.

Flood map

Where the water goes in Staines-upon-Thames

Turn layers on and off. Blue is the risk from rivers and the sea; pink is where heavy rain collects. Both allow for flood defences.

Recorded flood: 1947Recorded flood: 1968Recorded flood: 1974Recorded flood: 1988Recorded flood: 1990Recorded flood: 1993Recorded flood: 2000Recorded flood: 2002Recorded flood: 2012Recorded flood: 2013Recorded flood: 2014Recorded flood: 2024© OpenStreetMap contributors · EA NaFRA2
HighMediumLowrivers & seaHighMediumLowsurface waterStaines-upon-Thames’s built-up area

The river and sea risk follows the River Thames, the Colne Brook and the River Colne. Surface-water risk is patchier: dips, underpasses and small streams.

Rivers and the sea

24% of Staines-upon-Thames’s homes are at high or medium risk from rivers or the sea

The Environment Agency’s national map, allowing for defences. A further 40% are at low risk.

High risk12%of homes · 1 in 30 a year or more1,173 homes, EA count
Medium risk12%of homes · 1 in 30 to 1 in 1001,183 homes, EA count
Low risk40%of homes · 1 in 100 to 1 in 1,0004,484 homes, EA count
Where Staines-upon-Thames sits among 3,735 UK towns
35%None
23%Under 0.5%
9%0.5–1%
11%1–2%
11%2–5%
5%5–10%
3%10–20%
2%20% +Staines-upon-Thames

Share of each UK town’s homes at high or medium risk from rivers and the sea. 35% of UK towns have none; Staines-upon-Thames has more than 98% of towns.

Towns its size: 298th of 302 from the fewest homes at risk
#TownPeopleHigh or med.
1Northfleet Kent29,8920%
2Jarrow Tyne and Wear29,4670%
3Cramlington Northumberland28,8460%
…
296Skegness Lincolnshire20,70113%
297Hessle East Riding of Yorkshire15,48914%
298Staines-upon-Thames Surrey21,32724%
299Cleethorpes Lincolnshire29,66027%
300Egham Surrey28,00329%
301Wisbech Cambridgeshire26,80043%
302Goole East Riding of Yorkshire20,17394%

UK towns of 15,000 to 30,000 people.

The Environment Agency’s Risk of Flooding from Rivers and Sea (NaFRA2, June 2026) counts each postcode’s homes by band; the shares weight those postcodes by Census 2021 households. The EA counts include homes built since 2021.

Surface water

Rivers and the sea, more than heavy rain, are Staines-upon-Thames’s flood risk

Surface water is rain that falls faster than drains and the ground can take it. It is mapped separately from rivers and the sea, and it is not in the Hazard risk Grade.

Surface water1.5%
Rivers and the sea24%
0%35%70% of homes

About 0.3% of homes are at high risk of surface-water flooding (a 1 in 30 chance or more each year) and 1.2% at medium risk: roughly 140 households. A further 6.7% face a low risk from surface water. That is more than 16% of UK towns.

~140
households at high or medium risk
6.7%
of homes at low risk
16%
of UK towns have a smaller share
11,681
addresses read on the map

Our estimate: every address in the town (ONS NSUL) read on the Environment Agency’s Risk of Flooding from Surface Water map (NaFRA2, 2025), each postcode’s share weighted by its Census 2021 households. Neither agency publishes a count of homes for surface water, so treat it as a guide; one street can differ from the next.

Flood history

Staines-upon-Thames has flooded in 12 recorded years since 1947, most of all in 1947

Every flood the Environment Agency has mapped inside Staines-upon-Thames’s built-up area, newest first. The record is fullest for big river floods; small and surface-water floods are often missing.

  1. 2024January 2024: River flooding recordedUnder 1 hectare inside today’s built-up area
  2. 2014January 2014: River flooding recorded4 hectares inside today’s built-up area
  3. 2013November 2013: River flooding recorded136 hectares inside today’s built-up area
  4. 2012December 2012: River flooding recorded1 hectare inside today’s built-up area
  5. 2002December 2002: River flooding recorded97 hectares inside today’s built-up area
  6. 2000January 2000: River flooding recorded12 hectares inside today’s built-up area
Show all 12
  1. 1993January and October 1993: River flooding recorded2 hectares inside today’s built-up area
  2. 1990January 1990: River flooding recorded3 hectares inside today’s built-up area
  3. 1988January 1988: River flooding recorded3 hectares inside today’s built-up area
  4. 1974January 1974: River flooding recorded8 hectares inside today’s built-up area
  5. 1968January 1968: River flooding recorded199 hectares inside today’s built-up area
  6. 1947January 1947: River flooding recorded418 hectares inside today’s built-up area
The worst: 1947418 ha

Floodwater covered 418 hectares of what is now Staines-upon-Thames in 1947, the largest flood the record holds here (January).

4,737 of Staines-upon-Thames’s households today live inside the outline of a recorded flood.

Since 1947, the largest recorded flood inside the town covered 199 hectares.

River levels

The River Thames at Penton Hook: highest 1.40 m, in February 2014

The highest level each winter (October to September) at the Environment Agency’s Penton Hook gauge (Laleham), since 1994. The river normally runs between 0.08 m and 0.30 m here.

Highest level each winter, metres
Winter 1994–95: highest 0.67 m · 26 days above the normal rangeWinter 1995–96: highest 0.40 m · 25 days above the normal rangeWinter 1996–97: highest 0.38 m · 32 days above the normal rangeWinter 1997–98: highest 0.35 m · 26 days above the normal rangeWinter 1998–99: highest 0.48 m · 56 days above the normal rangeWinter 1999–00: highest 0.45 m · 42 days above the normal rangeWinter 2000–01: highest 1.03 m on 16 December 2000 · 93 days above the normal rangeWinter 2001–02: highest 0.66 m · 18 days above the normal rangeWinter 2002–03: highest 0.59 m · 27 days above the normal rangeWinter 2003–04: highest 0.39 m · 26 days above the normal rangeWinter 2004–05: highest 0.33 m · 13 days above the normal rangeWinter 2005–06: highest 0.39 m · 58 days above the normal rangeWinter 2006–07: highest 0.48 m · 135 days above the normal rangeWinter 2007–08: highest 0.51 m · 32 days above the normal rangeWinter 2008–09: highest 0.69 m · 21 days above the normal rangeWinter 2009–10: highest 0.39 m · 17 days above the normal rangeWinter 2010–11: highest 0.39 m · 21 days above the normal rangeWinter 2011–12: highest 0.43 m · 49 days above the normal rangeWinter 2012–13: highest 0.86 m on 28 December 2012 · 68 days above the normal rangeWinter 2013–14: highest 1.40 m on 11 February 2014 · 120 days above the normal rangeWinter 2014–15: highest 0.39 m · 66 days above the normal rangeWinter 2015–16: highest 0.41 m · 47 days above the normal rangeWinter 2016–17: highest 0.37 m · 31 days above the normal rangeWinter 2017–18: highest 0.39 m · 14 days above the normal rangeWinter 2018–19: highest 0.40 m · 30 days above the normal rangeWinter 2019–20: highest 0.76 m · 127 days above the normal rangeWinter 2020–21: highest 0.98 m on 3 February 2021 · 56 days above the normal rangeWinter 2021–22: highest 0.43 m · 39 days above the normal rangeWinter 2023–24: highest 1.39 m on 8 January 2024 · 102 days above the normal rangeWinter 2025–26: highest 0.61 m · 77 days above the normal range’13–14’23–24’00–01Record 1.40 m, 2014Top of normal range
1994–952025–26
The highest days on record
  • 11 February 20141.40 m
  • 8 January 20241.39 m
  • 11 January 20141.20 m
  • 16 December 20001.03 m
  • 3 February 20210.98 m
  • 19 February 20140.97 m

The River Thames has topped its normal range on 1,494 days since 1994, most in the winters of 2006–07 and 2019–20. By its highest day, the winter of 2025–26 was the 10th-highest of the 30.

Environment Agency Hydrology API, Penton Hook (station 2901TH), daily maximum level; the record and normal range from the EA’s stage scale. Live river levels are on GOV.UK’s Check for flooding.

Flood warnings

No flood warning or alert is in force for Staines-upon-Thames · 30 warnings in 20 years

The Environment Agency has 9 flood warning areas and 5 alert areas reaching into the town; warnings since the service began in 2006.

Now: no flood warnings or alerts for Staines-upon-Thames (checked 7 November 2026, 01:10). Check for flooding on GOV.UK →
Warnings and alerts each year for areas in Staines-upon-Thames
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
Flood warning (flooding expected)Flood alert (flooding possible)

The warning area covering the most of Staines-upon-Thames, Groundwater flooding in Egham, has not had a flood warning since 2006. Of the 30 warnings, 10 were for Colne Brook at Colnbrook and 6 for River Thames at Laleham.

2014 had the most warnings (12); 2024 the most alerts (31). The most recent warning was on 7 January 2024.

Show the 14 warning and alert areas
AreaKindSince 2006Now
Colne Brook at ColnbrookWarning area10None
Properties closest to the River Thames from Runnymede Pleasure Grounds, Staines to Penton HookWarning area6None
River Thames at LalehamWarning area6None
River Colne and Frays River at West Drayton and Stanwell MoorWarning area2None
Chertsey Bourne at ChertseyWarning area2None
Groundwater flooding in EghamWarning area0None
Chertsey Bourne at Thorpe GreenWarning area2None
River Thames at Staines and EghamWarning area1None
River Ash at Ashford and StainesWarning area1None
Chertsey BourneAlert area72None
Lower River Colne and Frays RiverAlert area38None
Colne Brook at Iver and ColnbrookAlert area29None
River Thames from Datchet to Shepperton GreenAlert area26None
River Ash in the Borough of SpelthorneAlert area1None

Environment Agency Historic Flood Warnings (first issues only, not updates; “flood watch” counted as an alert before 2011) and the real-time flood-monitoring API. Sign up for free warnings on GOV.UK or call Floodline, 0345 988 1188.

Radon

Staines-upon-Thames is in the lowest radon band

Radon is a natural radioactive gas from the ground; long exposure raises the risk of lung cancer. The atlas gives the chance that a home in each 1 km square is above the UK action level (200 Bq/m³).

TQ0267: Under 1% of homes above the action levelTQ0268: Under 1% of homes above the action levelTQ0269: Under 1% of homes above the action levelTQ0271: Under 1% of homes above the action levelTQ0272: Under 1% of homes above the action levelTQ0367: Under 1% of homes above the action levelTQ0368: Under 1% of homes above the action levelTQ0369: Under 1% of homes above the action levelTQ0370: Under 1% of homes above the action levelTQ0371: Under 1% of homes above the action levelTQ0372: Under 1% of homes above the action levelTQ0468: Under 1% of homes above the action levelTQ0469: Under 1% of homes above the action levelTQ0470: Under 1% of homes above the action levelTQ0471: Under 1% of homes above the action levelTQ0472: Under 1% of homes above the action levelTQ0569: Under 1% of homes above the action levelTQ0570: Under 1% of homes above the action levelTQ0571: Under 1% of homes above the action levelTQ0572: Under 1% of homes above the action levelTQ0670: Under 1% of homes above the action level© OpenStreetMap contributors · BGS/UKHSA
Under 1%
Share of the town’s area in each band
Under 1% of homes100%

Every 1 km square over Staines-upon-Thames is in the lowest band: fewer than 1 in 100 homes are expected to be above the action level.

BGS/UKHSA Indicative Atlas of Radon in Great Britain, version 3. Check an address at UKradon.org.

Neighbours

Flood risk in the places around Staines-upon-Thames

Share of homes at high or medium and at low risk from rivers and the sea. Tap a town for its page.

Laleham: Hazard risk D−Ashford: Hazard risk B−Stanwell: Hazard risk AThorpe: Hazard risk D−Stanwell Moor: Hazard risk B−Egham: Hazard risk D−Shepperton Green: Hazard risk D−LalehamAshfordStanwellThorpeStanwell MoorEghamShepperton GreenStaines-upon-Thames
ABCD
TownPeopleHigh or mediumLowHazard
Staines-upon-Thames21,32724%40%D−
Laleham2,52131%44%D−
Ashford22,8230.3%9%B−
Stanwell11,7280%0%A
Thorpe1,22613%8.6%D−
Stanwell Moor1,4310.4%0.6%B−
Egham28,00329%20%D−
Shepperton Green4,35821%61%D−

Laleham, 0.9 miles south, has the most homes at risk around Staines-upon-Thames (31% at high or medium). Stanwell has none.

Be ready

Get ready for what Staines-upon-Thames faces

Free warnings, what to do in a cloudburst, and what to check before you move.

Get the warnings
  • Sign up free for Environment Agency flood warnings by text, call or email.
  • Floodline: 0345 988 1188, 24 hours.
  • Staines-upon-Thames’s warning areas include River Thames at Staines and Egham and River Ash at Ashford and Staines.
Sign up ↗
In a cloudburst
  • Surface water rises in minutes, often with no warning issued: stay out of underpasses and dips.
  • Keep the gullies and drains outside your home clear of leaves.
  • Report a blocked road drain to the council.
When the river rises
  • Never walk or drive through floodwater: 30 cm of moving water can float a car.
  • Move valuables, papers and medicines upstairs.
  • Turn off gas, electricity and water if you’re told to.
Before you buy or rent in Staines-upon-Thames
  • Check the address on GOV.UK’s long-term flood risk service: it gives rivers and sea and surface water separately.
  • Ask whether the home has flooded or had a flood insurance claim; the TA6 property form asks the seller.
  • Homes built before 2009 can get flood cover through Flood Re, the government-backed scheme; newer homes can’t.
How to read these numbers

What this data can and can’t tell you

  • Defences are counted. Both agencies’ maps allow for flood defences and the chance they are overtopped or fail, so a town behind a defence scheme can show few homes at high risk and many at low risk.
  • Surface water is our estimate. Neither agency publishes a count of homes at risk from surface water, so we read each address on the map. A flat on a hill and a basement in a dip can share a postcode.
  • Past floods are what was recorded. The flood outlines come from surveys, aerial photographs and reports; many small floods, and most surface-water floods, were never mapped.
  • One town, many streets. Risk is street by street. Check a specific address on GOV.UK’s long-term flood risk service before you buy or rent.

Check the long-term flood risk for an address on GOV.UK →

Questions about flooding and hazards in Staines-upon-Thames

Does Staines-upon-Thames flood?

The last flood the Environment Agency recorded inside the town was in January 2024. 24% of homes are at high or medium risk from rivers and the sea on the Environment Agency’s maps, which allow for flood defences. About 1.5% of homes are at high or medium risk from surface water, when heavy rain overwhelms the drains. Staines-upon-Thames grades D− for hazard risk against UK towns.

Which parts of Staines-upon-Thames are at risk of flooding?

From rivers and the sea, the places the Environment Agency warns directly: Colne Brook at Colnbrook, River Thames at Laleham, Properties closest to the River Thames from Runnymede Pleasure Grounds, Staines to Penton Hook and River Colne and Frays River at West Drayton and Stanwell Moor. Surface water can collect in low spots anywhere in the town. Check a specific address on GOV.UK’s long-term flood risk service.

When did Staines-upon-Thames last flood?

The recorded flood outlines inside the town run from 1947 to 2024 (12 years); the largest was in 1947. Flood warnings have been issued for parts of the town since 2006, most recently on 7 January 2024.

Is Staines-upon-Thames at risk of surface water flooding?

About 0.3% of homes are at high risk and 1.2% at medium risk from surface water, against 24% at high or medium risk from rivers and the sea. Surface water floods come with little warning, and the agencies don’t issue warnings for them.

Is radon a problem in Staines-upon-Thames?

Not by the atlas: every 1 km square over Staines-upon-Thames is in the lowest band, where fewer than 1 in 100 homes are expected to be above the action level.

Are there flood warnings in Staines-upon-Thames now?

No flood warning or alert was in force near Staines-upon-Thames at 7 November 2026, 01:10. Live warnings are on GOV.UK’s Check for flooding service and Floodline, 0345 988 1188.

Contains Environment Agency information © Environment Agency and/or database right 2026. Contains British Geological Survey materials © UKRI 2026.

Sources: Environment Agency Risk of Flooding from Rivers and Sea, postcodes in areas at risk (June 2026); Natural Resources Wales Flood Risk Assessment Wales (May 2026); ONS Census 2021 households by postcode · Environment Agency Risk of Flooding from Surface Water (NaFRA2, 2025) and Natural Resources Wales Flood Risk Assessment Wales surface water and small watercourses, read at every address (ONS National Statistics UPRN Lookup, September 2026) and weighted by Census 2021 households by postcode · Environment Agency Recorded Flood Outlines and Natural Resources Wales historic flood map, inside the ONS 2022 built-up-area boundary · Environment Agency Hydrology API (daily maximum river level) and flood-monitoring stage scales · Environment Agency real-time flood-monitoring API · Environment Agency Historic Flood Warnings (January 2006 to June 2026) and flood warning and alert areas · BGS/UKHSA Indicative Atlas of Radon in Great Britain, version 3, by 1 km square · TownRatings grades: our own summary of the data, ranked against UK towns only. All under the Open Government Licence v3.0.

Contains public sector information licensed under the Open Government Licence v3.0. Contains HM Land Registry data © Crown copyright and database right 2026. Contains OS data © Crown copyright and database right 2026 (ONS boundaries). Northern Ireland: Source: NISRA; contains Land & Property Services data and Ordnance Survey of Northern Ireland information, © Crown copyright, licensed under the Open Government Licence v3.0. Scotland: contains National Records of Scotland data, Registers of Scotland data and SEPA data, © Crown copyright / © SEPA 2025, licensed under the Open Government Licence v3.0.