Photo: Loozrboy from Toronto, Canada · CC BY-SA 2.0Cornell faces fewer hazards than 88% of Canadian towns
Since 1986 almost nothing has burned near Cornell: 0% of the land within 25 km, or 0.001% a year. Earthquake risk in Cornell is ordinary: NRCan’s model puts building losses at $0.034 a year per $1,000 of value, close to the typical town’s $0.030. Fewer homes than usual carry radon here, 0% over the guideline where the typical town has 6.6%. Cornell grades A for hazard risk, with wildfire counted against it.
What stands out about Cornell’s hazards
For Cornell, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Cornell faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Cornell grades A for hazard risk
Risk averages earthquakes and radon; wildfire joins only where it pulls the average down, so a town like Cornell with little fire nearby would get no credit for it.
Its place: #165 of 866 in Ontario and #484 of 2,589 Canadian towns.
How sure: The seismic figure is a long-run average from NRCan’s model, not a prediction. The burned-area record misses fires under about 10 ha and most grass and farm fires.
Little of the land around Cornell has burned: 0% within 5 km, 0% within 25 km since 1986
Past fire around Cornell’s homes, from the national burned-area record, with the fuel within 5 km.
Next to the typical Canadian town (0.000% a year), Cornell’s 0.001% is in the low band.
The 5 km ring around Cornell’s homes is clear of burns since 1986, the nearest 5.9 km out.
Close to Cornell there is little to burn (4.5% forest fuel within 5 km), but 8.5% of the land within 25 km is forest.
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
In the top quarter in Ontario: Cornell ranks 83rd of 871 at 0.001% a year, with Sioux Lookout first at 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.
Low, like 92% of the country’s 2,610 towns: the land around Cornell burns, but slower than in the 7.5% above it.
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 Cornell, the newest from Toronto Regional Conservation Authority
What Canada’s Flood Map Inventory lists for Cornell: who studied flooding and where to see their maps.
For Cornell the inventory points to 2 studies, most recently Toronto Regional Conservation Authority’s in 2021.
| Study | By | Year | Status |
|---|---|---|---|
| Toronto Floodline Consolidation | Toronto Regional Conservation Authority | 2021 | final |
| Duffins Creek | Toronto and Region Conservation Authority | 2020 | final |
Towns with a flood study on file
69% of towns in Ontario have a flood study, more than Canada’s 58%; Cornell has one too.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
The grade leaves flood out, since a study area says nothing about how many of Cornell’s homes are at risk.
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 Cornell: $0.034 per $1,000 of buildings a year
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
Cornell’s $0.034 is close to the typical town’s $0.030 (1.1 times as much).
Behind earthquake risk sits data gathered across the city of Markham, with Cornell one part of it.
Shaking damage a year per $1,000 of building value
Cornell’s $0.034 sits under the median in Ontario, $0.043, and well under 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.
Cornell’s earthquake risk lands near the centre of Canada’s range; 46% 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).
For Cornell the model prices shaking damage to buildings, nothing more.
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 Cornell: 0% of area homes over the guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline. · Area-wide: radon tests, counted over the York Regional Health Unit
Where the typical Canadian town has 6.6% of homes over the guideline, Cornell’s area has fewer, 0%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Fewer homes top the guideline around Cornell (0%) 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.
Cornell 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.
Whatever Cornell’s area share, the reading that matters is your own home’s, over a winter.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Where to get warnings in Cornell
Environment and Climate Change Canada issues the weather alerts for Cornell; 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. |
For fires near Cornell, the national fire information system maps danger and active fires daily; local authorities give any evacuation order.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How Cornell’s neighbours compare on hazards
Wildfire band, earthquake risk, radon and flood studies for each place nearby.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Cornell | Low | $0.034 | 0% | Yes |
| Upper Cornell 8,304 · 1.2 km | Low | $0.034 | 0% | Yes |
| Greensborough 19,270 · 2.5 km | Low | $0.034 | 0% | Yes |
| Markham Village 10,319 · 2.6 km | Low | $0.034 | 0% | Yes |
| Mount Joy 8,345 · 2.9 km | Low | $0.034 | 0% | Yes |
| Box Grove 25,496 · 4.0 km | Low | $0.034 | 0% | Yes |
| Wismer Commons 20,591 · 4.1 km | Low | $0.034 | 0% | Yes |
Upper Cornell (low) has the heaviest fire record of Cornell’s neighbours, and Cornell (low) matches or beats it.
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Cornell faces
What to do about the hazards Cornell 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
- Wildfire counts one way. Burned land within 25 km of where people live, averaged over 1986–2025 and checked for fuel near homes, is the measure; it looks back, not ahead, and only ever counts against Cornell.
- 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 Cornell sits in.
- 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 Cornell floods.
- Earthquakes are modelled. The earthquake figure is an expected loss, not a forecast, worked out by NRCan for each census subdivision, Cornell’s included.
Questions about flooding and hazards in Cornell
Is Cornell at risk of wildfire?
Fire has reached 0% of the land around Cornell since 1986 (last in 2001); at low, it neither helps nor hurts the grade.
Does Cornell flood?
Cornell’s area has been studied for flooding, and the owner’s map shows which streets lie in a zone; the grade leaves flood out.
How big is the earthquake risk in Cornell?
In NRCan’s seismic model, Cornell’s buildings lose $0.034 per $1,000 of value in an average year.
How is Cornell’s Hazard risk Grade worked out?
Cornell’s Hazard risk grade is A, built on earthquakes and radon with a one-sided wildfire input.
Is radon a problem in Cornell?
Around Cornell, 95 survey homes were tested and 0% 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).