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High Street, Lechlade (geograph 6225703)Photo: Philip Pankhurst · CC BY-SA 2.0
C+Hazard risk Grade
Flood & hazards in Lechlade-on-Thames · Environment Agency

Surface water, more than the river, is Lechlade-on-Thames’s flood risk: 2.9% of homes, against 0.4% 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. Hazard risk puts Lechlade-on-Thames at C+.

1947worst recorded flood3flood warnings since 20060%at low risk
In brief

What stands out about Lechlade-on-Thames’s hazards

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

Rain, more than the river2.9% of homes sit where heavy rain can flood the streets, against 0.4% at risk from rivers and the sea.Remembers 1947Floodwater covered 35 hectares of today’s Lechlade-on-Thames in 1947; 74 of today’s households live inside past flood outlines.The River Thames ran its 4th-highest in November 20240.84 m at St Johns Lock on 26 November 2024, 10 cm under the record set in 1995.3 flood warnings since 2006For the parts of Lechlade-on-Thames the Environment Agency warns directly; the most recent on 25 November 2024.
By hazard

What Lechlade-on-Thames faces

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

Rivers and the sea

0.4%of homes at high or medium risk
More than the typical UK town · more than 56% of towns
5 homes by the EA’s own count

Surface water

2.9%of homes at high or medium risk
More than 40% of UK towns
Rivers and sea: 0.4%

Past floods

4years with a recorded flood
Last recorded: July 2007
74 households inside past outlines

The River Thames

0.61 mhighest in winter 2025–26 at St Johns Lock
17th-highest of 31 winters
Record 0.95 m, November 1995

Flood warnings

3flood warnings since 2006
99 flood alerts for the wider area
Last warning 25 November 2024

Radon

0%of the village 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

Lechlade-on-Thames grades C+ for hazard risk

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

Homes at high or medium flood risk (0.4%)Fewer than 44% 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 Lechlade-on-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: 1977Recorded flood: 1992Recorded flood: 2007© OpenStreetMap contributors · EA NaFRA2
HighMediumLowrivers & seaHighMediumLowsurface waterLechlade-on-Thames’s built-up area

The river and sea risk follows the River Thames, the Blunsdon Brook and the Water Eaton Brook. Surface-water risk is spread across the village, in dips, underpasses and along small streams, which is why more homes are exposed to it.

Rivers and the sea

0.4% of Lechlade-on-Thames’s homes are at high or medium risk from rivers or the sea

The Environment Agency’s national map, allowing for defences. None are in the low-risk band.

High risk0.2%of homes · 1 in 30 a year or more3 homes, EA count
Medium risk0.2%of homes · 1 in 30 to 1 in 1002 homes, EA count
Low risk0%of homes · 1 in 100 to 1 in 1,0000 homes, EA count
Where Lechlade-on-Thames sits among 3,735 UK towns
35%None
23%Under 0.5%Lechlade-on-Thames
9%0.5–1%
11%1–2%
11%2–5%
5%5–10%
3%10–20%
2%20% +

Share of each UK town’s homes at high or medium risk from rivers and the sea. 35% of UK towns have none; Lechlade-on-Thames has more than 56% of towns.

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

Heavy rain puts about 7 times as many Lechlade-on-Thames homes at risk as rivers and the sea do

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 water2.9%
Rivers and the sea0.4%
0%7%14% of homes

About 0.9% of homes are at high risk of surface-water flooding (a 1 in 30 chance or more each year) and 2% at medium risk: roughly 40 households. A further 6% face a low risk from surface water. That is more than 40% of UK towns.

~40
households at high or medium risk
6%
of homes at low risk
40%
of UK towns have a smaller share
1,346
addresses read on the map

Our estimate: every address in the village (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

Lechlade-on-Thames has flooded in 4 recorded years since 1947, most of all in 1947

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

  1. 2007July 2007: River flooding recorded8 hectares inside today’s built-up area
  2. 1992January 1992: River flooding recordedUnder 1 hectare inside today’s built-up area
  3. 1977January 1977: River flooding recorded1 hectare inside today’s built-up area
  4. 1947January 1947: River flooding recorded35 hectares inside today’s built-up area
The worst: 194735 ha

Floodwater covered 35 hectares of what is now Lechlade-on-Thames in 1947, the largest flood the record holds here (January).

74 of Lechlade-on-Thames’s households today live inside the outline of a recorded flood.

Since 1947, the largest recorded flood inside the village covered 8 hectares.

River levels

The River Thames in November 2024 rose to its 4th-highest level since 1995

The highest level each winter (October to September) at the Environment Agency’s St Johns Lock gauge (Lechlade On Thames), since 1995. The river normally runs between -0.01 m and 0.25 m here.

Highest level each winter, metres
Winter 1995–96: highest 0.95 m on 23 November 1995 · 29 days above the normal rangeWinter 1996–97: highest 0.35 m · 3 days above the normal rangeWinter 1997–98: highest 0.54 m · 25 days above the normal rangeWinter 1998–99: highest 0.76 m · 38 days above the normal rangeWinter 1999–00: highest 0.61 m · 28 days above the normal rangeWinter 2000–01: highest 0.79 m on 14 December 2000 · 68 days above the normal rangeWinter 2001–02: highest 0.61 m · 34 days above the normal rangeWinter 2002–03: highest 0.80 m on 3 January 2003 · 37 days above the normal rangeWinter 2003–04: highest 0.45 m · 26 days above the normal rangeWinter 2004–05: highest 0.58 m · 10 days above the normal rangeWinter 2005–06: highest 0.49 m · 21 days above the normal rangeWinter 2006–07: highest 0.90 m on 22 July 2007 · 51 days above the normal rangeWinter 2007–08: highest 0.78 m on 16 January 2008 · 33 days above the normal rangeWinter 2008–09: highest 0.62 m · 16 days above the normal rangeWinter 2009–10: highest 0.42 m · 23 days above the normal rangeWinter 2010–11: highest 0.31 m · 6 days above the normal rangeWinter 2011–12: highest 0.32 m · 11 days above the normal rangeWinter 2012–13: highest 0.76 m · 56 days above the normal rangeWinter 2013–14: highest 0.77 m · 58 days above the normal rangeWinter 2014–15: highest 0.34 m · 9 days above the normal rangeWinter 2015–16: highest 0.65 m · 25 days above the normal rangeWinter 2016–17: highest 0.32 m · 11 days above the normal rangeWinter 2017–18: highest 0.45 m · 16 days above the normal rangeWinter 2018–19: highest 0.32 m · 13 days above the normal rangeWinter 2019–20: highest 10.64 m on 19 December 2019 · 64 days above the normal rangeWinter 2020–21: highest 0.69 m · 57 days above the normal rangeWinter 2021–22: highest 0.43 m · 17 days above the normal rangeWinter 2022–23: highest 0.74 m · 57 days above the normal rangeWinter 2023–24: highest 0.81 m on 6 January 2024 · 94 days above the normal rangeWinter 2024–25: highest 0.84 m on 26 November 2024 · 66 days above the normal rangeWinter 2025–26: highest 0.61 m · 36 days above the normal range’19–20’95–96’06–07Record 0.95 m, 1995Top of normal range
1995–962025–26
The highest days on record
  • 19 December 201910.64 m
  • 23 November 19950.95 m
  • 22 July 20070.90 m
  • 26 November 20240.84 m
  • 6 January 20240.81 m
  • 3 January 20030.80 m

The River Thames has topped its normal range on 1,038 days since 1995, most in the winters of 2023–24 and 2000–01. By its highest day, the winter of 2025–26 was the 17th-highest of the 31.

Environment Agency Hydrology API, St Johns Lock (station 0701TH), 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 Lechlade-on-Thames · 3 warnings in 20 years

The Environment Agency has 3 flood warning areas and 3 alert areas reaching into the village; warnings since the service began in 2006.

Now: no flood warnings or alerts for Lechlade-on-Thames (checked 13 November 2026, 03:46). Check for flooding on GOV.UK →
Warnings and alerts each year for areas in Lechlade-on-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 Lechlade-on-Thames, River Coln for Cotswold Water Park and Whelford, has not had a flood warning since 2006. Of the 3 warnings, 2 were for River Thames from Calcutt to Lechlade including Hannington Wick and 1 for River Leach from just below Southrop to Mill Lane near Lechlade.

2012 had the most warnings (2); 2023 the most alerts (15). The most recent warning was on 25 November 2024.

Show the 6 warning and alert areas
AreaKindSince 2006Now
River Thames from Calcutt to Lechlade including Hannington WickWarning area2None
River Leach from just below Southrop to Mill Lane near LechladeWarning area1None
River Coln for Cotswold Water Park and WhelfordWarning area0None
River Thames and its small tributaries from Calcutt to LechladeAlert area51None
River Leach from Northleach to Mill Lane near LechladeAlert area25None
River Coln and its tributariesAlert area23None

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

Lechlade-on-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).

SU1899: Under 1% of homes above the action levelSP1800: Under 1% of homes above the action levelSU1999: Under 1% of homes above the action levelSU2099: Under 1% of homes above the action levelSP2000: Under 1% of homes above the action levelSU2199: Under 1% of homes above the action levelSP2100: Under 1% of homes above the action levelSP2200: Under 1% of homes above the action level© OpenStreetMap contributors · BGS/UKHSA
Under 1%
Share of the village’s area in each band
Under 1% of homes100%

Every 1 km square over Lechlade-on-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 Lechlade-on-Thames

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

Fairford: Hazard risk DHighworth: Hazard risk AFaringdon: Hazard risk BCarterton: Hazard risk BBampton: Hazard risk C−Shrivenham and Watchfield: Hazard risk B+Broad Blunsdon: Hazard risk AFairfordHighworthFaringdonCartertonBamptonShrivenham and WatchfieldBroad BlunsdonLechlade-on-Thames
ABCD
TownPeopleHigh or mediumLowHazard
Lechlade-on-Thames2,2080.4%0%C+
Fairford4,2405.9%3.3%D
Highworth7,9320%0%A
Faringdon8,625under 0.1%under 0.1%B
Carterton17,951under 0.1%0%B
Bampton2,9942.4%2.4%C−
Shrivenham and Watchfield5,3530%under 0.1%B+
Broad Blunsdon6,5070%0%A

Fairford, 3.8 miles west, has the most homes at risk around Lechlade-on-Thames (5.9% at high or medium). Highworth, Shrivenham and Watchfield and Broad Blunsdon have none.

Be ready

Get ready for what Lechlade-on-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.
  • Lechlade-on-Thames’s warning areas include River Coln for Cotswold Water Park and Whelford and River Thames from Calcutt to Lechlade including Hannington Wick.
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 Lechlade-on-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 Lechlade-on-Thames

Does Lechlade-on-Thames flood?

The last flood the Environment Agency recorded inside the village was in July 2007. 0.4% 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 2.9% of homes are at high or medium risk from surface water, when heavy rain overwhelms the drains. Lechlade-on-Thames grades C+ for hazard risk against UK towns.

Which parts of Lechlade-on-Thames are at risk of flooding?

From rivers and the sea, the places the Environment Agency warns directly: River Thames from Calcutt to Lechlade including Hannington Wick, River Leach from just below Southrop to Mill Lane near Lechlade and River Coln for Cotswold Water Park and Whelford. Surface water can collect in low spots anywhere in the village. Check a specific address on GOV.UK’s long-term flood risk service.

When did Lechlade-on-Thames last flood?

The recorded flood outlines inside the village run from 1947 to 2007 (4 years); the largest was in 1947. Flood warnings have been issued for parts of the village since 2006, most recently on 25 November 2024.

Is Lechlade-on-Thames at risk of surface water flooding?

About 0.9% of homes are at high risk and 2% at medium risk from surface water, against 0.4% 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 Lechlade-on-Thames?

Not by the atlas: every 1 km square over Lechlade-on-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 Lechlade-on-Thames now?

No flood warning or alert was in force near Lechlade-on-Thames at 13 November 2026, 03:46. 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.