Photo: Jason Zhang · CC0A flood study covers Steeles: 1 on the national inventory, the newest from Toronto Regional Conservation Authority
The burned-area map is nearly blank around Steeles, 0% within 25 km since 1986, 0.001% a year. Shaking is about as much of a worry in Steeles as in most places, at $0.043 a year per $1,000 of building value ($0.030 typical). In Health Canada’s survey, just 2.7% of homes tested in the area exceeded 200 Bq/m³ (6.6% typical). Steeles grades A− for hazard risk, with wildfire counted against it.
What stands out about Steeles’s hazards
Four national sources, each read for Steeles: earthquakes, radon, past fires and flood studies.
What Steeles faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Steeles grades A− for hazard risk
Two inputs always count for Steeles, earthquakes and radon; the third, wildfire, counts only against a town.
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. Small fires and grass fires are largely missing from the national burned-area record.
Little of the land around Steeles has burned: 0% within 5 km, 0% within 25 km since 1986
Past fire around Steeles’ homes, from the national burned-area record, with the fuel within 5 km.
Fire claims 0.001% of the land around Steeles each year, a low band, with the typical Canadian town at 0.000%.
Nothing inside 5 km of Steeles’ homes has burned since 1986, and the nearest scar is 13 km off.
Only 4.3% of the land within 25 km of Steeles is forest fuel, and 0.1% 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, Steeles 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.
The low band takes in 92% of Canada’s 2,610 towns, Steeles among them, though its rate is above zero; 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.
Steeles is on the flood map inventory: 1 study, by Toronto Regional Conservation Authority
What Canada’s Flood Map Inventory lists for Steeles: who studied flooding and where to see their maps.
The flood study touching Steeles 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
Mapping in Ontario reaches 69% of towns, Steeles included, beside 58% across Canada.
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 Steeles.
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.
Ordinary seismic risk in Steeles: $0.043 per $1,000 of buildings a year
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
Nothing unusual about Steeles’ ground: $0.043 against a typical $0.030, 1.4 times.
Steeles doesn’t get its own earthquake risk figures; the ones here come from the city of Toronto.
Shaking damage a year per $1,000 of building value
Earthquake risk around Steeles ($0.043) matches the middle in Ontario ($0.043), far from 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.
Steeles’ 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).
The model counts damage to Steeles’ 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).
2.7% of homes tested around Steeles are over the radon guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline.
Steeles’ area, at 2.7%, 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
Fewer homes top the guideline around Steeles (2.7%) than in the typical town in Ontario (4%).
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
The quietest radon band, under 5%, holds 37% of Canada’s 2,611 towns and Steeles; 63% sit higher.
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.
One home in Steeles can be high while next door is low; a three-month test settles it.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011). · Area behind the radon tests figures: the City of Toronto Health Unit
Weather and fire alerts for Steeles
Environment and Climate Change Canada issues the weather alerts for Steeles; 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 Steeles, and listen to local authorities for orders.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How Steeles’ neighbours compare on hazards
Wildfire band, earthquake risk, radon and flood studies for each place nearby.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Steeles | Low | $0.043 | 2.7% | Yes |
| Milliken 12,138 · 1.8 km | Low | $0.034 | 0% | Yes |
| East L'Amoreaux 21,533 · 2.3 km | Low | $0.043 | 2.7% | Yes |
| Underwood 5,972 · 2.4 km | Low | $0.034 | 0% | None listed |
| L'Amoreaux West 21,575 · 2.4 km | Low | $0.043 | 2.7% | Yes |
| Hillcrest Village 16,374 · 3.0 km | Low | $0.043 | 2.7% | Yes |
| Pleasant View 15,248 · 3.1 km | Low | $0.043 | 2.7% | None listed |
Milliken (low) has the heaviest fire record of Steeles’ neighbours, and Steeles (low) matches or beats it.
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Steeles faces
What to do about the hazards Steeles 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
- Flood studies aren’t flood zones. A study’s area can be a whole watershed or province, so being on the inventory says a map exists, not that a home in Steeles floods.
- Wildfire counts one way. The wildfire figure is the share of land within 25 km of Steeles’ homes burned each year from 1986 to 2025, past fire rather than a forecast, and it can only lower Risk.
- Radon is a survey. The radon share comes from about 14,000 long-term home tests in 2009–2011, pooled for now by the 2007 health region Steeles sits in.
- 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 Steeles’.
Questions about flooding and hazards in Steeles
Does Steeles flood?
Steeles’ area has been studied for flooding, and the owner’s map shows which streets lie in a zone; the grade leaves flood out.
Is radon a problem in Steeles?
Around Steeles, 74 survey homes were tested and 2.7% came in over 200 Bq/m³, a guide to the area, not to any one home.
Is Steeles at risk of wildfire?
Fire has reached 0% of the land around Steeles since 1986 (last in 2001); at low, it neither helps nor hurts the grade.
How is Steeles’s Hazard risk Grade worked out?
Steeles grades A− for hazard risk, from earthquakes and radon, with wildfire counted only where it lowers the grade.
How big is the earthquake risk in Steeles?
In NRCan’s seismic model, Steeles’ buildings lose $0.043 per $1,000 of value in an average year.
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).