Photo: WabbitWanderer from London, Canada · CC BY-SA 2.0Hazard risk in Westmount is lower than in 90% of Canadian towns
Since 1986 almost nothing has burned near Westmount: 0% of the land within 25 km, or 0.000% a year. Shaking is about as much of a worry in Westmount as in most places, at $0.020 a year per $1,000 of building value ($0.030 typical). In Health Canada’s survey, just 1.8% of homes tested in the area exceeded 200 Bq/m³ (6.6% typical). Westmount grades A for hazard risk; wildfire is low here, so it earns no credit.
What stands out about Westmount’s hazards
Four national sources, each read for Westmount: earthquakes, radon, past fires and flood studies.
What Westmount faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Westmount grades A for hazard risk
For Westmount, Risk will be the average of earthquakes and radon, with wildfire added only if it makes the average worse.
Its place: #43 of 866 in Ontario and #347 of 2,589 Canadian towns.
How sure: Earthquake losses are a model’s expectation over many years, not a forecast for any one. Small fires and grass fires are largely missing from the national burned-area record.
Wildfire is rare near Westmount: 0% of the land within 25 km burned since 1986, 0% within 5 km
Past fire around Westmount’s homes, from the national burned-area record, with the fuel within 5 km.
In a typical year 0.000% of the land near Westmount burns; the typical Canadian town sees 0.000%, and both are low.
With 0.4% forest fuel within 5 km and 0.4% within 25 km, the land around Westmount 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
To three decimals the burn rate around Westmount is zero, as for 638 of the 871 towns in Ontario, while Sioux Lookout reaches 0.16%.
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 Westmount 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.
No flood study is listed for Westmount
What Canada’s Flood Map Inventory lists for Westmount: who studied flooding and where to see their maps.
Canada’s Flood Map Inventory lists no study whose area touches Westmount, which doesn’t mean it has never been mapped.
Towns with a flood study on file
69% of towns in Ontario have a flood study, more than Canada’s 58%; Westmount is not yet one of them.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
Nothing here counts toward Risk; the studies are pointers to the maps their owners keep for Westmount.
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.”
Expected shaking damage in Westmount: $0.020 a year per $1,000
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
0.7 times the typical $0.030: Westmount’s $0.020 is ordinary.
For earthquake risk, the only official count covers all of the city of London, Westmount included.
Shaking damage a year per $1,000 of building value
The typical town in Ontario expects $0.043 a year in shaking damage; Westmount expects less, $0.020, and Alexandria the most, $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.
Westmount sits mid-range among Canada’s 2,611 towns: 64% expect more shaking damage.
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 loss is to Westmount’s buildings alone, from ground shaking; infrastructure and secondary hazards are left out.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean).
Radon runs low around Westmount: 1.8% of tested homes over the guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline.
Westmount’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
Radon runs lower around Westmount than in most towns in Ontario: 1.8% against 4%.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Few tests over the guideline: Westmount shares the bottom band with 37% of Canada’s 2,611 towns, below the other 63%.
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.
Basements, soil and how a house is sealed decide its radon, so in Westmount only a test can say.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011). · Area behind the radon tests figures: the Middlesex-London Health Unit
Weather and fire alerts for Westmount
Environment and Climate Change Canada issues the weather alerts for Westmount; 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 Westmount, and listen to local authorities for orders.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How Westmount’s neighbours compare on hazards
Wildfire band, earthquake risk, radon and flood studies for each place nearby.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Westmount | Low | $0.020 | 1.8% | None listed |
| Southcrest 14,477 · 2.1 km | Low | $0.020 | 1.8% | None listed |
| Talbot 8,085 · 2.3 km | Low | $0.020 | 1.8% | None listed |
| Bostwick 7,694 · 2.9 km | Low | $0.020 | 1.8% | Yes |
| Byron 15,277 · 3.0 km | Low | $0.020 | 1.8% | None listed |
| Highland 19,963 · 3.3 km | Low | $0.020 | 1.8% | None listed |
| Oakridge 16,247 · 3.4 km | Low | $0.020 | 1.8% | None listed |
The neighbour with the most fire is Southcrest (low), still no more than Westmount (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Westmount faces
Practical steps for Westmount’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?
- Ask the municipality for flood maps.
- Are flood and wildfire insured?
What this data can and can’t tell you
- Wildfire counts one way. The wildfire figure is the share of land within 25 km of Westmount’s homes burned each year from 1986 to 2025, past fire rather than a forecast, and it can only lower Risk.
- Radon is a survey. About 14,000 homes were tested across Canada in 2009–2011, and the share over the guideline for Westmount is its health region’s, the survey’s design unit.
- Flood studies aren’t flood zones. NRCan’s inventory says where flood mapping exists, not where water goes; the map’s owner is the authority for Westmount.
- Earthquakes are modelled. Shaking damage is modelled from the ground, the buildings and the odds of each quake, and published for whole subdivisions such as Westmount’s.
Questions about flooding and hazards in Westmount
Does Westmount flood?
No study on Canada’s Flood Map Inventory covers Westmount (0), which doesn’t mean it has never been mapped, so ask the municipality.
How is Westmount’s Hazard risk Grade worked out?
Westmount’s Hazard risk grade is A, built on earthquakes and radon with a one-sided wildfire input.
How big is the earthquake risk in Westmount?
NRCan’s model expects shaking to cost buildings in Westmount $0.020 a year for every $1,000 of their value, on average over many years.
Is Westmount at risk of wildfire?
Hardly at all on record: 0% of the land within 25 km of Westmount since 1986, a low band, though small grass fires aren’t mapped.
Is radon a problem in Westmount?
1.8% of the 110 homes Health Canada tested around Westmount topped the guideline; your own house needs its own test.
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).