Photo: andrewarchy from Toronto, Canada · CC BY 2.0A quiet place for hazards: low wildfire, little earthquake risk, and 2.7% of tested homes over the radon guideline in Yonge-Doris’ area
Wildfire isn’t Yonge-Doris’ worry: 0% of the land within 25 km burned since 1986 (0.001% a year). Shaking is about as much of a worry in Yonge-Doris as in most places, at $0.043 a year per $1,000 of building value ($0.030 typical). Yonge-Doris grades A− for hazard risk, with wildfire counted against it.
What stands out about Yonge-Doris’s hazards
Four national sources, each read for Yonge-Doris: earthquakes, radon, past fires and flood studies.
What Yonge-Doris faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Yonge-Doris: A−
Risk averages earthquakes and radon; wildfire joins only where it pulls the average down, so a town like Yonge-Doris with little fire nearby would get no credit for it.
Its place: #285 of 866 in Ontario and #700 of 2,589 Canadian towns.
How sure: Earthquake losses are a model’s expectation over many years, not a forecast for any one. Only 74 homes were tested in the survey area, so the radon share is rough. Small fires and grass fires are largely missing from the national burned-area record.
Wildfire is rare near Yonge-Doris: 0% of the land within 25 km burned since 1986, 0% within 5 km
Past fire around Yonge-Doris’ homes, from the national burned-area record, with the fuel within 5 km.
A burn rate of 0.001% a year keeps Yonge-Doris in the low band (the typical Canadian town: 0.000%).
Yonge-Doris’ homes have had no fire within 5 km since 1986; the closest was 23 km away.
Only 2.5% of the land within 25 km of Yonge-Doris is forest fuel, and 0.2% close in.
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
At 0.001% a year, Yonge-Doris is near the top in Ontario: 83rd of 871, behind Sioux Lookout (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.
Beside 2,610 Canadian towns, Yonge-Doris reads low, with 92% of them; only 7.5% rank higher.
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 Yonge-Doris
What Canada’s Flood Map Inventory lists for Yonge-Doris: who studied flooding and where to see their maps.
Canada’s Flood Map Inventory lists no study whose area touches Yonge-Doris, which doesn’t mean it has never been mapped.
Towns with a flood study on file
Yonge-Doris has no flood study on file, though 69% of towns in Ontario do (Canada: 58%).
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
Flood studies don’t enter the grade; they are listed so you can open the official map for Yonge-Doris.
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.”
Ordinary seismic risk in Yonge-Doris: $0.043 per $1,000 of buildings a year
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
Nothing unusual about Yonge-Doris’ ground: $0.043 against a typical $0.030, 1.4 times.
Shaking damage a year per $1,000 of building value
The median in Ontario is $0.043; Yonge-Doris, at $0.043, is right beside it, and Alexandria tops the list 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.
Yonge-Doris sits mid-range among Canada’s 2,611 towns: 36% 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).
Roads, pipes and bridges aren’t in Yonge-Doris’ figure, nor landslides or tsunami: it is buildings and shaking.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean). · Earthquake risk published for the city of Toronto, not by town
Little radon around Yonge-Doris: 2.7% of area homes over the guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline. · Source area for radon tests: the City of Toronto Health Unit
Fewer homes than usual test high around Yonge-Doris: 2.7% against 6.6% for the typical Canadian town.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Yonge-Doris’ area, at 2.7%, 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.
Yonge-Doris 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.
A survey sample isn’t a map: any home in Yonge-Doris 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).
Weather and fire alerts for Yonge-Doris
Alerts for Yonge-Doris come from Environment and Climate Change Canada and, for emergencies, Alert Ready.
| 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. |
Alert Ready carries evacuation orders for Yonge-Doris to phones; CWFIS shows the day’s fire danger.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
Hazards in the places around Yonge-Doris
Wildfire band, earthquake risk, radon and flood studies for each place nearby.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Yonge-Doris | Low | $0.043 | 2.7% | None listed |
| Willowdale West 17,210 · 0.8 km | Low | $0.043 | 2.7% | Yes |
| East Willowdale 15,514 · 0.9 km | Low | $0.043 | 2.7% | Yes |
| Avondale 13,803 · 1.3 km | Low | $0.043 | 2.7% | Yes |
| Lansing-Westgate 15,980 · 1.8 km | Low | $0.043 | 2.7% | Yes |
| Newtonbrook West 23,978 · 2.3 km | Low | $0.043 | 2.7% | Yes |
| Newtonbrook East 15,996 · 2.3 km | Low | $0.043 | 2.7% | Yes |
None of the places around has more fire nearby than Yonge-Doris (low); Willowdale West comes closest (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Yonge-Doris faces
What to do about the hazards Yonge-Doris 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?
- Ask the municipality for flood maps.
- Are flood and wildfire insured?
What this data can and can’t tell you
- 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 Yonge-Doris.
- 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 Yonge-Doris’.
- Wildfire counts one way. The wildfire figure is the share of land within 25 km of Yonge-Doris’ 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 Yonge-Doris is its health region’s, the survey’s design unit.
Questions about flooding and hazards in Yonge-Doris
Does Yonge-Doris flood?
Nothing is listed for Yonge-Doris on the national inventory (0); local maps may still exist with the municipality.
How is Yonge-Doris’s Hazard risk Grade worked out?
Yonge-Doris’ Hazard risk grade is A−, built on earthquakes and radon with a one-sided wildfire input.
Is Yonge-Doris at risk of wildfire?
Less than most of Canada: 0% of the land within 25 km of Yonge-Doris has burned since 1986, the last in 2001, a low band that leaves Risk alone.
Is radon a problem in Yonge-Doris?
In Health Canada’s survey, 2.7% of 74 homes tested in Yonge-Doris’ area were above 200 Bq/m³, though only a test tells you about one house.
How big is the earthquake risk in Yonge-Doris?
NRCan’s model expects shaking to cost buildings in Yonge-Doris $0.043 a year for every $1,000 of their value, on average over many years.
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).