Photo: Michael Garlick · CC BY-SA 2.04.5% of Salisbury’s homes are at high or medium flood risk from rivers or the sea, 3.4% from surface water
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. For hazard risk, Salisbury grades D.
What stands out about Salisbury’s hazards
From the Environment Agency’s maps and records and the BGS radon atlas, below.
What Salisbury faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Rivers and the sea
Surface water
Past floods
The River Bourne
Flood warnings
Radon
Salisbury grades D for hazard risk
Flood risk from rivers and the sea, against all 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.
Where the water goes in Salisbury
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.
The river and sea risk follows the Groundwater, the River Bourne and the Hampshire River Avon. Surface-water risk is patchier: dips, underpasses and small streams.
4.5% of Salisbury’s homes are at high or medium risk from rivers or the sea
The Environment Agency’s national map, allowing for defences. A further 6.8% are at low risk.
Share of each UK town’s homes at high or medium risk from rivers and the sea. 35% of UK towns have none; Salisbury has more than 89% of towns.
| # | Town | People | High or med. | |
|---|---|---|---|---|
| 1 | Dudley West Midlands | 64,277 | 0% | |
| 2 | Smethwick West Midlands | 56,343 | 0% | |
| 3 | Bootle Merseyside | 53,722 | 0% | |
| … | ||||
| 148 | Carlton Nottinghamshire | 53,555 | 4.1% | |
| 149 | Caerphilly Gwent | 33,104 | 4.3% | |
| 150 | Salisbury Wiltshire | 47,690 | 4.5% | |
| 151 | Loughborough Leicestershire | 64,850 | 4.6% | |
| 152 | Newbury Berkshire | 42,262 | 4.6% | |
| … | ||||
| 158 | Exmouth Devon | 35,502 | 9.8% | |
| 159 | Caversham Berkshire | 33,038 | 13% | |
UK towns of 33,000 to 67,000 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.
3.4% of Salisbury’s homes are at high or medium risk from surface water
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.
About 1.5% of homes are at high risk of surface-water flooding (a 1 in 30 chance or more each year) and 1.9% at medium risk: roughly 710 households. A further 4.6% face a low risk from surface water. That is more than 47% of UK towns.
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.
Salisbury has flooded in 3 recorded years since 1959, most of all in 1959
Every flood the Environment Agency has mapped inside Salisbury’s built-up area, newest first. The record is fullest for big river floods; small and surface-water floods are often missing.
- 2014January and February 2014: River flooding recorded2 hectares inside today’s built-up area
- 1982March 1982: River flooding recorded1 hectare inside today’s built-up area
- 1959January 1959: River flooding recorded36 hectares inside today’s built-up area · Avon & Frome
Floodwater covered 36 hectares of what is now Salisbury in 1959, the largest flood the record holds here (January).
50 of Salisbury’s households today live inside the outline of a recorded flood.
Since 1959, the largest recorded flood inside the town covered 2 hectares.
The River Bourne in February 2026 rose to its 3rd-highest level since 2004
The highest level each winter (October to September) at the Environment Agency’s Salisbury Bourne gauge, since 2004. The river normally runs between 0.65 m and 1.22 m here.
- 7 January 20241.83 m
- 14 February 20141.79 m
- 19 February 20261.64 m
- 6 February 20141.63 m
- 22 February 20141.63 m
- 11 February 20261.59 m
The River Bourne has topped its normal range on 438 days since 2004, most in the winters of 2023–24 and 2013–14. By its highest day, the winter of 2025–26 was the 3rd-highest of the 22.
Environment Agency Hydrology API, Salisbury Bourne (station 43159), 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.
No flood warning or alert is in force for Salisbury · 59 warnings in 20 years
The Environment Agency has 16 flood warning areas and 4 alert areas reaching into the town; warnings since the service began in 2006.
The warning area covering the most of Salisbury, Groundwater flooding in the Salisbury Plain area, has not had a flood warning since 2006. Of the 59 warnings, 18 were for Middle Hampshire Avon from Salisbury to Ringwood and 11 for Middle Hampshire Avon at St Marys Cathedral area, Salisbury.
2024 had the most warnings (16). The most recent warning was on 10 February 2026.
Show the 20 warning and alert areas
| Area | Kind | Since 2006 | Now |
|---|---|---|---|
| Groundwater flooding in the Cranborne Chase area | Warning area | 0 | None |
| Middle Hampshire Avon from Salisbury to Ringwood | Warning area | 18 | None |
| Groundwater flooding in the Salisbury Plain area | Warning area | 0 | None |
| Middle Hampshire Avon at St Marys Cathedral area, Salisbury | Warning area | 11 | None |
| River Nadder, Tisbury to West Harnham | Warning area | 11 | None |
| Middle Hampshire Avon at The Close and West Harnham, Salisbury | Warning area | 6 | None |
| River Bourne at Southampton Road Industrial Park, Salisbury | Warning area | 6 | None |
| Middle Hampshire Avon at The Friary and City Centre, Salisbury | Warning area | 2 | None |
| Groundwater flooding for the Avon valley from Amesbury to the north of Salisbury | Warning area | 2 | None |
| Middle Hampshire Avon at Southampton Road Retail and Business Parks, Salisbury | Warning area | 1 | None |
| Upper Hampshire Avon at Stratford sub Castle, low lying properties, Salisbury | Warning area | 1 | None |
| Upper Hampshire Avon at Millstream and Avon Approach, Salisbury | Warning area | 1 | None |
| River Nadder at West Harnham | Warning area | 0 | None |
| River Bourne from Winterbourne Gunner to Southampton Road in Laverstock | Warning area | 0 | None |
| Upper Hampshire Avon at St Pauls and City Centre, Salisbury | Warning area | 0 | None |
| Upper Hampshire Avon at Stratford sub Castle, Salisbury | Warning area | 0 | None |
| River Nadder and tributaries | Alert area | 70 | None |
| Upper Hampshire Avon and tributaries | Alert area | 38 | None |
| Middle Hampshire Avon and tributaries | Alert area | 23 | None |
| River Bourne and tributaries | Alert area | 21 | None |
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.
Parts of Salisbury are in radon Affected Areas, at the low end
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).
56% of Salisbury’s built-up area is in a radon Affected Area (1% of homes or more above the action level).
The squares are indicative: each takes the highest band found anywhere inside it, so most homes in a coloured square are below it. Only a three-month test in the home gives a real answer.
BGS/UKHSA Indicative Atlas of Radon in Great Britain, version 3. Check an address at UKradon.org.
Flood risk in the places around Salisbury
Share of homes at high or medium and at low risk from rivers and the sea. Tap a town for its page.
| Town | People | High or medium | Low | Hazard |
|---|---|---|---|---|
| Salisbury | 47,690 | 4.5% | 6.8% | D |
| Old Sarum | 4,013 | 0% | 0% | A |
| Wilton | 4,300 | 12% | 9% | D− |
| Whaddon | 2,283 | 0% | under 0.1% | B+ |
| Downton | 2,952 | 0.6% | 9.8% | C+ |
| Amesbury | 12,676 | 0% | 0% | A |
| Middle Winterslow | 1,563 | 0% | 0% | A |
| Redlynch and Woodfalls | 2,446 | 0% | 0% | A |
Wilton, 2.7 miles west, has the most homes at risk around Salisbury (12% at high or medium).
Get ready for what Salisbury faces
Free warnings, what to do in a cloudburst, and what to check before you move.
- Sign up free for Environment Agency flood warnings by text, call or email.
- Floodline: 0345 988 1188, 24 hours.
- Salisbury’s warning areas include Groundwater flooding in the Salisbury Plain area and Groundwater flooding in the Cranborne Chase area.
- 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.
- Test over three months, in a living room and a bedroom.
- Above 200 Bq/m³, a small sump and fan usually fixes it.
- New homes in radon areas are built with protection: basic from 3%, full from 10%.
- 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.
- Check radon for the address on UKradon.org (a small fee) or ask the seller for a test result.
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.
Questions about flooding and hazards in Salisbury
Does Salisbury flood?
The last flood the Environment Agency recorded inside the town was in February 2014. 4.5% 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 3.4% of homes are at high or medium risk from surface water, when heavy rain overwhelms the drains. Salisbury grades D for hazard risk against UK towns.
Which parts of Salisbury are at risk of flooding?
From rivers and the sea, the places the Environment Agency warns directly: Middle Hampshire Avon from Salisbury to Ringwood, Middle Hampshire Avon at St Marys Cathedral area, Salisbury, River Nadder, Tisbury to West Harnham and Middle Hampshire Avon at The Close and West Harnham, Salisbury. 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 Salisbury last flood?
The recorded flood outlines inside the town run from 1959 to 2014 (3 years); the largest was in 1959. Flood warnings have been issued for parts of the town since 2006, most recently on 10 February 2026.
Is Salisbury at risk of surface water flooding?
About 1.5% of homes are at high risk and 1.9% at medium risk from surface water, against 4.5% 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 Salisbury?
56% of the town’s built-up area is in a radon Affected Area on the BGS/UKHSA atlas. Most homes are below it; a three-month test is the only way to know.
Are there flood warnings in Salisbury now?
No flood warning or alert was in force near Salisbury at 7 November 2026, 12:21. 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.