Photo: Oaktree b · CC BY-SA 4.0A flood study covers Willowdale West: 1 on the national inventory, the newest from Toronto Regional Conservation Authority
Wildfire barely registers for Willowdale West, at 0% of the land within 25 km since 1986 (0.001% a year). NRCan expects $0.043 of shaking damage a year per $1,000 of buildings in Willowdale West, near the typical $0.030. In Health Canada’s survey, just 2.7% of homes tested in the area exceeded 200 Bq/m³ (6.6% typical). Willowdale West grades A− for hazard risk, with wildfire counted against it.
What stands out about Willowdale West’s hazards
For Willowdale West, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Willowdale West faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Willowdale West grades A− for hazard risk
The grade weighs Willowdale West’s seismic risk and radon equally, and wildfire is one-sided: a high band counts against a town, a low one earns nothing.
Its place: #285 of 866 in Ontario and #700 of 2,589 Canadian towns.
How sure: The seismic figure is a long-run average from NRCan’s model, not a prediction. The radon share rests on 74 home tests in the survey area, so a few homes move it. The burned-area record misses fires under about 10 ha and most grass and farm fires.
Wildfire is rare near Willowdale West: 0% of the land within 25 km burned since 1986, 0% within 5 km
Fires mapped since 1986 around where Willowdale West’s residents live, and the fuel next to their homes.
Next to the typical Canadian town (0.000% a year), Willowdale West’s 0.001% is in the low band.
Since 1986 the nearest fire to Willowdale West’s homes came within 24 km, never inside 5 km.
Around Willowdale West the forest is thin or far off: 0.2% of the land within 5 km and 2.4% within 25 km is forest fuel.
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 burns fastest in Ontario at 0.16% a year; Willowdale West, at 0.001%, ranks 83rd of 871.
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.
7.5% of Canada’s 2,610 towns burn fast enough to rank moderate or above; Willowdale West stays low, with 92%.
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.
Willowdale West is on the flood map inventory: 1 study, by Toronto Regional Conservation Authority
Flood studies whose area touches Willowdale West, from NRCan’s inventory, each linked to its owner.
The flood study touching Willowdale West is Toronto Regional Conservation Authority’s, dated 2021; its own map shows the zones street by street.
| Study | By | Year | Status |
|---|---|---|---|
| Toronto Floodline Consolidation | Toronto Regional Conservation Authority | 2021 | final |
Towns with a flood study on file
Flood maps are common in Ontario: 69% of towns have one, against 58% nationally, and Willowdale West is among 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 Willowdale West.
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 Willowdale West $0.043 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.
1.4 times the typical $0.030: Willowdale West’s $0.043 is ordinary.
For earthquake risk, the only official count covers all of the city of Toronto, Willowdale West included.
Shaking damage a year per $1,000 of building value
Typical for its province: Willowdale West at $0.043 beside a median in Ontario of $0.043, with Alexandria on top at $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.
Willowdale West’s earthquake risk lands near the centre of Canada’s range; 36% of the 2,611 towns are higher.
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).
Only shaking damage to buildings in Willowdale West is counted; landslides, liquefaction, tsunami and fire after a quake aren’t.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean).
2.7% of homes tested around Willowdale West are over the radon guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline. · Measured across the City of Toronto Health Unit: radon tests
At 2.7% over the guideline, the area around Willowdale West is under the typical Canadian town’s 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Against the typical town in Ontario (4%), the area around Willowdale West has fewer high tests: 2.7%.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Willowdale West is in the lowest band, with 37% of Canada’s 2,611 towns: under 5% of tests over the guideline, while 63% have more.
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.
Neighbouring homes in Willowdale West can differ a lot; only a long-term test tells you about yours.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Where to get warnings in Willowdale West
Environment and Climate Change Canada issues the weather alerts for Willowdale West; 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 Willowdale West, and listen to local authorities for orders.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How Willowdale West’s neighbours compare on hazards
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Willowdale West | Low | $0.043 | 2.7% | Yes |
| Yonge-Doris 20,298 · 0.8 km | Low | $0.043 | 2.7% | None listed |
| Newtonbrook West 23,978 · 1.5 km | Low | $0.043 | 2.7% | Yes |
| East Willowdale 15,514 · 1.6 km | Low | $0.043 | 2.7% | Yes |
| Avondale 13,803 · 2.0 km | Low | $0.043 | 2.7% | Yes |
| Newtonbrook East 15,996 · 2.1 km | Low | $0.043 | 2.7% | Yes |
| Lansing-Westgate 15,980 · 2.1 km | Low | $0.043 | 2.7% | Yes |
Nowhere around Willowdale West burns more: Yonge-Doris, the closest rival, is low to its low.
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Willowdale West faces
What to do about the hazards Willowdale West faces, and what to ask before you buy.
- 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
- Earthquakes are modelled. Seismic risk is NRCan’s model of yearly building losses from shaking, averaged over many years and given for Willowdale West’s census subdivision (a neighbourhood shows its city’s).
- Wildfire counts one way. For Willowdale West, wildfire means how much nearby land burned in the past forty years, a one-way input that can pull Risk down and nothing more.
- 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 Willowdale West until then.
- Flood studies aren’t flood zones. Flood studies cover areas of every size, which is why the page lists them for Willowdale West without grading them.
Questions about flooding and hazards in Willowdale West
How is Willowdale West’s Hazard risk Grade worked out?
Willowdale West’s Hazard risk grade is A−, built on earthquakes and radon with a one-sided wildfire input.
Is radon a problem in Willowdale West?
In Health Canada’s survey, 2.7% of 74 homes tested in Willowdale West’s area were above 200 Bq/m³, though only a test tells you about one house.
Does Willowdale West flood?
A flood study covers Willowdale West on Canada’s Flood Map Inventory; open the owner’s map to check a street, since flood isn’t graded.
Is Willowdale West at risk of wildfire?
Less than most of Canada: 0% of the land within 25 km of Willowdale West has burned since 1986, the last in 2001, a low band that leaves Risk alone.
How big is the earthquake risk in Willowdale West?
Expected earthquake damage in Willowdale West comes to $0.043 a year for each $1,000 that buildings are worth.
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).