Hazard risk in Dufferin Hill is lower than in 90% of Canadian towns
For Dufferin Hill, wildfire history is close to nil: 0% of nearby land since 1986, 0.000% a year. Seismic risk in Dufferin Hill sits near the middle: $0.028 of expected damage per $1,000 of buildings a year, the typical town $0.030. Radon is lower than usual: 0% of tested homes in the survey area topped the guideline, against 6.6% for the typical town. Hazard risk gives Dufferin Hill a grade of A, from earthquakes and radon alone.
What stands out about Dufferin Hill’s hazards
Four national sources, each read for Dufferin Hill: earthquakes, radon, past fires and flood studies.
What Dufferin Hill faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Dufferin Hill grades A for hazard risk
Seismic risk and radon set Dufferin Hill’s grade, wildfire can drag it down, and flood mapping stays out of it.
Its place: #74 of 866 in Ontario and #383 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 Dufferin Hill: 0% of the land within 25 km burned since 1986, 0% within 5 km
Fires mapped since 1986 around where Dufferin Hill’s residents live, and the fuel next to their homes.
A burn rate of 0.000% a year keeps Dufferin Hill in the low band (the typical Canadian town: 0.000%).
Little near Dufferin Hill’s homes can carry a forest fire; only 0.6% of the land within 5 km is forest fuel, and 3.7% within 25 km.
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
Of the 871 towns in Ontario, 638 have a burn rate that rounds to zero, Dufferin Hill among them; Sioux Lookout leads at 0.16% a year.
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.
Most of the country’s 2,610 towns are low-band (92%, against 7.5% above); around Dufferin Hill, burning rounds to zero.
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.
Toronto Regional Conservation Authority has mapped flooding for Dufferin Hill (1 study)
Flood studies whose area touches Dufferin Hill, from NRCan’s inventory, each linked to its owner.
For Dufferin Hill the inventory points to Toronto Regional Conservation Authority’s 2021 study, whose map is the one to check.
| 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, Dufferin Hill 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.
Flood studies don’t enter the grade; they are listed so you can open the official map for Dufferin Hill.
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 Dufferin Hill: $0.028 per $1,000 of buildings a year
NRCan’s seismic risk model: the damage shaking is expected to do to buildings each year, on average over many years.
Earthquake losses in Dufferin Hill, $0.028 per $1,000, are in line with the typical $0.030 (0.9 times).
Behind earthquake risk sits data gathered across the city of Vaughan, with Dufferin Hill one part of it.
Shaking damage a year per $1,000 of building value
At $0.028, Dufferin Hill is below the typical town in Ontario ($0.043); Alexandria is highest 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.
Around half of Canada’s 2,611 towns expect more shaking damage than Dufferin Hill (51%).
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 Dufferin Hill’s 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).
Little radon around Dufferin Hill: 0% of area homes over the guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline. · Area-wide: radon tests, counted over the York Regional Health Unit
Dufferin Hill’s survey area reads 0% over the guideline, 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 Dufferin Hill has fewer high tests: 0%.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
63% of Canada’s 2,611 towns have a higher share of homes over 200 Bq/m³ than Dufferin Hill’s band, which holds 37%.
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 Dufferin Hill only a test can say.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Weather and fire alerts for Dufferin Hill
Alerts for Dufferin Hill 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 Dufferin Hill 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 Dufferin Hill
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Dufferin Hill | Low | $0.028 | 0% | Yes |
| Crossroads 4,525 · 1.6 km | Low | $0.028 | 0% | Yes |
| Carrville Corners 13,004 · 1.7 km | Low | $0.028 | 0% | Yes |
| Thornhill Woods 13,237 · 1.7 km | Low | $0.028 | 0% | Yes |
| The Valleys of Thornhill 9,979 · 2.4 km | Low | $0.028 | 0% | Yes |
| Maple 20,122 · 2.9 km | Low | $0.028 | 0% | Yes |
| Beverley Glen 38,720 · 4.1 km | Low | $0.028 | 0% | Yes |
Beverley Glen burns a little more than Dufferin Hill, in the same low band (low here).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Dufferin Hill faces
Practical steps for Dufferin Hill’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
- Radon is a survey. Health Canada’s survey tested some 14,000 homes over three months; until postal-area boundaries are loaded, Dufferin Hill takes its 2007 health region’s share.
- 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 Dufferin Hill’s.
- Flood studies aren’t flood zones. The flood inventory points to maps; it is incomplete and not the official source, so ask the municipality about any street in Dufferin Hill.
- Wildfire counts one way. The wildfire figure is the share of land within 25 km of Dufferin Hill’s homes burned each year from 1986 to 2025, past fire rather than a forecast, and it can only lower Risk.
Questions about flooding and hazards in Dufferin Hill
Does Dufferin Hill flood?
The inventory lists a study touching Dufferin Hill; whether a given street floods is on that map, not in the grade.
How big is the earthquake risk in Dufferin Hill?
Expected earthquake damage in Dufferin Hill comes to $0.028 a year for each $1,000 that buildings are worth.
Is radon a problem in Dufferin Hill?
0% of the 95 homes Health Canada tested around Dufferin Hill topped the guideline; your own house needs its own test.
How is Dufferin Hill’s Hazard risk Grade worked out?
Dufferin Hill grades A for hazard risk, from earthquakes and radon, with wildfire counted only where it lowers the grade.
Is Dufferin Hill at risk of wildfire?
Hardly at all on record: 0% of the land within 25 km of Dufferin Hill since 1986, a low band, though small grass fires aren’t mapped.
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).