Photo: Chris Woodrich · CC BY-SA 4.0Strathroy faces fewer hazards than 92% of Canadian towns
Wildfire barely registers for Strathroy, at 0% of the land within 25 km since 1986 (0.000% a year). Seismic risk in Strathroy sits near the middle: $0.018 of expected damage per $1,000 of buildings a year, the typical town $0.030. Fewer homes than usual carry radon here, 1.8% over the guideline where the typical town has 6.6%. Hazard risk gives Strathroy a grade of A, from earthquakes and radon alone.
What stands out about Strathroy’s hazards
Four national sources, each read for Strathroy: earthquakes, radon, past fires and flood studies.
What Strathroy faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Strathroy grades A for hazard risk
For Strathroy, Risk will be the average of earthquakes and radon, with wildfire added only if it makes the average worse.
Its place: #33 of 866 in Ontario and #285 of 2,589 Canadian towns.
How sure: The seismic figure is a long-run average from NRCan’s model, not a prediction. Small fires and grass fires are largely missing from the national burned-area record.
Little of the land around Strathroy has burned: 0% within 5 km, 0% within 25 km since 1986
Fires mapped since 1986 around where Strathroy’s residents live, and the fuel next to their homes.
The land within 25 km of Strathroy burns at 0.000% a year on average, the low band; the typical Canadian town: 0.000%.
With 0.3% forest fuel within 5 km and 0.3% within 25 km, the land around Strathroy gives a fire little to burn.
Shares of land within 5 and 25 km of populated blocks: burned at least once in 1986–2025 (CWFIS burned-area composite), forest fuel and grass (fire behaviour fuel types, 2026, 250 m grid).
Burn rate a year, towns in Ontario · highest of 871
Sioux Lookout has the highest burn rate in Ontario, 0.16% a year; around Strathroy, as around 638 of the 871 towns, it rounds to zero.
Each bar: the yearly average share of land within 25 km of a town’s homes that burned, 1986–2025 (CWFIS); the seven highest towns of 2,500 people or more.
The low band holds 92% of Canada’s 2,610 towns, and Strathroy sits at its very bottom; only 7.5% are above it.
Bands of the yearly burn rate: low under 0.05%, moderate under 0.25%, high under 1%, very high 1% or more; towns of 2,500 people or more.
Fire danger and active fires (CWFIS)
Canadian Wildland Fire Information System: National Burned Area Composite 1986–2025 and fire behaviour fuel types (2026), Natural Resources Canada. Measured within 25 km and 5 km of each populated dissemination area; past fire, not a forecast.
St. Clair Region Conservation Authority has mapped flooding for Strathroy (1 study)
Flood studies whose area touches Strathroy, from NRCan’s inventory, each linked to its owner.
The flood study touching Strathroy is St. Clair Region Conservation Authority’s, dated 2009; its own map shows the zones street by street.
| Study | By | Year | Status |
|---|---|---|---|
| SCRCA Floodplain Estimation Study for Ontario Regulation 171-06 | St. Clair Region Conservation Authority | 2009 | final · not public |
Towns with a flood study on file
Flood maps are common in Ontario: 69% of towns have one, against 58% nationally, and Strathroy is among them.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
Flood is shown here, never graded: a study says where a map exists, not how many of Strathroy’s homes stand in a flood zone.
The inventory’s own caution (NRCan): “The Canada Flood Map (CFM) does not include every flood hazard map in Canada and may be incomplete or contain inaccuracies. It should not be relied upon as the official source of flood mapping information. Furthermore, if a map appears to be missing, this does not necessarily mean that the area has never been mapped. For the official version of a map, updated information, or confirmation of applicable regulations, please contact the local authority responsible for flood mapping.”
Natural Resources Canada, Canada Flood Map Inventory; links go to each study’s owner.
Earthquakes cost buildings in Strathroy $0.018 per $1,000 a year
NRCan’s seismic risk model: the damage shaking is expected to do to buildings each year, on average over many years.
With $0.018 of shaking damage a year per $1,000, Strathroy is about even with the typical $0.030 (0.6 times).
Shaking damage a year per $1,000 of building value
Strathroy’s $0.018 sits under the median in Ontario, $0.043, and well under Alexandria’s $0.21.
NRCan seismic risk model (2022): mean yearly building loss per $1,000 of value; medians of towns of 2,500 people or more.
Toward the quiet end of Canada’s range: 68% of its 2,611 towns sit above Strathroy.
Each column: the share of Canada’s towns of 2,500 people or more in that range of yearly loss per $1,000 (NRCan, 2022).
The model counts damage to Strathroy’s buildings and their occupants from shaking only: not liquefaction, landslides, tsunami or fires after a quake.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean).
1.8% of homes tested around Strathroy are over the radon guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline.
Strathroy’s area, at 1.8%, is below the 6.6% of the typical Canadian town, though any one home can still be high.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Strathroy’s area, at 1.8%, is below the median in Ontario (4%).
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Under 5% puts Strathroy with 37% of Canada’s 2,611 towns; 63% have more high tests.
Each bar: the share of Canada’s towns of 2,500 people or more whose survey area had that share of tests over 200 Bq/m³.
A survey sample isn’t a map: any home in Strathroy can be high, and a three-month test is the only way to know.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011). · Radon tests: one figure for all of the Middlesex-London Health Unit
Weather and fire alerts for Strathroy
Environment and Climate Change Canada issues the weather alerts for Strathroy; Alert Ready carries the urgent ones to phones, radio and TV.
| Alert | What it means |
|---|---|
| Warning | Severe weather is happening or about to: act now. |
| Watch | Conditions favour severe weather: be ready. |
| Advisory | Weather that is less severe but could disrupt the day. |
| Special weather statement | Unusual weather worth knowing about. |
| Special air quality statement | Poor air, often wildfire smoke. |
In fire season, check CWFIS for danger and active fires around Strathroy, and listen to local authorities for orders.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How Strathroy’s neighbours compare on hazards
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Strathroy | Low | $0.018 | 1.8% | Yes |
| Adelaide-Metcalfe 3,196 · 5.6 km | Low | $0.018 | 1.8% | Yes |
| Middlesex Centre 21,689 · 17 km | Low | $0.018 | 1.8% | Yes |
| River Bend 5,930 · 18 km | Low | $0.020 | 1.8% | None listed |
Among its neighbours Strathroy has the most fire on record (low); Adelaide-Metcalfe follows (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Strathroy faces
Practical steps for Strathroy’s hazards, most pressing first.
- Test for three months in winter.
- Over 200 Bq/m³: fix it.
- Kits are cheap; pros test too.
- Never drive through floodwater.
- Move papers and medicines upstairs.
- Ask whether your street is mapped.
- Clear needles and wood nearby.
- Keep a grab-and-go bag ready.
- In smoke, stay in; filter air.
- Has it had a radon test?
- Check the address on the flood map.
- Are flood and wildfire insured?
What this data can and can’t tell you
- Wildfire counts one way. Wildfire is read from the national burned-area record around Strathroy’s homes since 1986, a history of fire that may lower Risk but never raises it.
- Radon is a survey. Radon figures pool the survey’s home tests by area: postal areas once their boundaries arrive, the 2007 health region around Strathroy until then.
- Flood studies aren’t flood zones. Flood studies cover areas of every size, which is why the page lists them for Strathroy without grading them.
- Earthquakes are modelled. NRCan models what earthquakes would cost buildings each year on average, subdivision by subdivision; Strathroy’s figure is its subdivision’s.
Questions about flooding and hazards in Strathroy
Is Strathroy at risk of wildfire?
Very little by the national record: Strathroy’s band is low, with 0% of the land within 25 km burned since 1986, so wildfire doesn’t change its grade.
How big is the earthquake risk in Strathroy?
Expected earthquake damage in Strathroy comes to $0.018 a year for each $1,000 that buildings are worth.
Does Strathroy flood?
A flood study covers Strathroy on Canada’s Flood Map Inventory; open the owner’s map to check a street, since flood isn’t graded.
Is radon a problem in Strathroy?
1.8% of the 110 homes Health Canada tested around Strathroy topped the guideline; your own house needs its own test.
How is Strathroy’s Hazard risk Grade worked out?
Strathroy’s Hazard risk grade is A, built on earthquakes and radon with a one-sided wildfire input.
Seismic risk: Natural Resources Canada. Radon: Health Canada. Wildfire: Canadian Wildland Fire Information System. Flood studies: Natural Resources Canada, Canada Flood Map Inventory. Contains information licensed under the Open Government Licence – Canada.
Sources: NRCan, Canada’s Seismic Risk Model 2022 · Health Canada, Cross-Canada Survey of Radon Concentrations in Homes · CWFIS, National Burned Area Composite and FBP fuel types · NRCan, Canada Flood Map Inventory. Under the Statistics Canada Open Licence.
Adapted from Statistics Canada (Census of Population 2021, population estimates 2025, 2021 census boundaries) under the Statistics Canada Open Licence; this does not constitute an endorsement by Statistics Canada. Neighbourhood names in some cities © OpenStreetMap contributors (ODbL).