Photo: GTD Aquitaine · Public domainA flood study covers Weston: 2 on the national inventory, the newest from Toronto Regional Conservation Authority
No wildfire is mapped within 25 km of Weston’s homes since 1986 (0% of the land, 0.000% a year). For earthquakes Weston is middling, $0.043 a year per $1,000 against $0.030 for the typical town. Radon is lower than usual: 2.7% of tested homes in the survey area topped the guideline, against 6.6% for the typical town. Weston grades A− for hazard risk; wildfire is low here, so it earns no credit.
What stands out about Weston’s hazards
Four national sources, each read for Weston: earthquakes, radon, past fires and flood studies.
What Weston faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Weston: A−
Risk averages earthquakes and radon; wildfire joins only where it pulls the average down, so a town like Weston 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: The seismic figure is a long-run average from NRCan’s model, not a prediction. 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.
Few fires near Weston: 0% within 5 km, 0% within 25 km
Fires mapped since 1986 around where Weston’s residents live, and the fuel next to their homes.
Low by Canadian standards: 0.000% of the land a year around Weston, 0.000% for the typical Canadian town.
Little near Weston’s homes can carry a forest fire; only 0.5% of the land within 5 km is forest fuel, and 1% 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
Sioux Lookout has the highest burn rate in Ontario, 0.16% a year; around Weston, as around 638 of the 871 towns, it rounds to zero.
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.
Weston shares the low band with 92% of Canada’s 2,610 towns, its burn rate rounding to nothing; 7.5% burn faster.
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.
2 flood studies cover Weston, the newest from Toronto Regional Conservation Authority
Flood studies whose area touches Weston, from NRCan’s inventory, each linked to its owner.
2 studies on the inventory touch Weston, the newest Toronto Regional Conservation Authority’s from 2021, and their areas can be large, so they say maps exist, not that the town floods.
| Study | By | Year | Status |
|---|---|---|---|
| Toronto Floodline Consolidation | Toronto Regional Conservation Authority | 2021 | final |
| Rockcliffe Special Policy Area | Toronto and Region Conservation Authority | 2020 | final |
Towns with a flood study on file
Its flood study puts Weston with 69% of towns in Ontario; Canada’s share is 58%.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
Listed, not scored: a flood study proves a map exists, not that Weston floods.
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.
Expected shaking damage in Weston: $0.043 a year per $1,000
NRCan’s seismic risk model: the damage shaking is expected to do to buildings each year, on average over many years.
Nothing unusual about Weston’s 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; Weston, 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.
Weston 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).
The model counts damage to Weston’s 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). · Area behind the earthquake risk figures: the city of Toronto
Little radon around Weston: 2.7% of area homes over the guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline.
A lower share than most: 2.7% of tested homes around Weston, the typical Canadian town 6.6%. Figures for radon tests are published for the City of Toronto Health Unit as a whole, not for Weston alone.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Weston’s 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.
Weston 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.
One home in Weston 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).
Weather and fire alerts for Weston
Alerts for Weston 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. |
Fire danger and active fires near Weston are mapped daily by the Canadian Wildland Fire Information System; evacuation orders come from the municipality or province.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How Weston’s neighbours compare on hazards
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Weston | Low | $0.043 | 2.7% | Yes |
| Humber Heights-Westmount 10,427 · 1.1 km | Low | $0.043 | 2.7% | Yes |
| Rustic 9,543 · 1.9 km | Low | $0.043 | 2.7% | Yes |
| Brookhaven-Amesbury 17,541 · 2.1 km | Low | $0.043 | 2.7% | Yes |
| Mount Dennis 13,364 · 2.3 km | Low | $0.043 | 2.7% | Yes |
| Pelmo Park-Humberlea 11,396 · 2.5 km | Low | $0.043 | 2.7% | Yes |
| Oakdale-Beverley Heights 21,386 · 2.7 km | Low | $0.043 | 2.7% | Yes |
The neighbour with the most fire is Humber Heights-Westmount (low), still no more than Weston (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Weston faces
What to do about the hazards Weston 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. NRCan models what earthquakes would cost buildings each year on average, subdivision by subdivision; Weston’s figure is its subdivision’s.
- Flood studies aren’t flood zones. Flood studies cover areas of every size, which is why the page lists them for Weston without grading them.
- Wildfire counts one way. Wildfire is read from the national burned-area record around Weston’s homes since 1986, a history of fire that may lower Risk but never raises it.
- 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 Weston until then.
Questions about flooding and hazards in Weston
How big is the earthquake risk in Weston?
Expected earthquake damage in Weston comes to $0.043 a year for each $1,000 that buildings are worth.
Does Weston flood?
A flood study covers Weston on Canada’s Flood Map Inventory; open the owner’s map to check a street, since flood isn’t graded.
Is Weston at risk of wildfire?
Very little by the national record: Weston’s band is low, with 0% of the land within 25 km burned since 1986, so wildfire doesn’t change its grade.
How is Weston’s Hazard risk Grade worked out?
Weston grades A− for hazard risk, from earthquakes and radon, with wildfire counted only where it lowers the grade.
Is radon a problem in Weston?
Around Weston, 74 survey homes were tested and 2.7% came in over 200 Bq/m³, a guide to the area, not to any one home.
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).