Photo: SimonP · CC BY-SA 3.0Humber Summit is on Canada’s flood inventory: 1 listed, led by Toronto Regional Conservation Authority
Wildfire barely registers for Humber Summit, at 0% of the land within 25 km since 1986 (0.000% a year). Seismic risk in Humber Summit sits near the middle: $0.043 of expected damage per $1,000 of buildings a year, the typical town $0.030. In Health Canada’s survey, just 2.7% of homes tested in the area exceeded 200 Bq/m³ (6.6% typical). Humber Summit grades A− for hazard risk; wildfire is low here, so it earns no credit.
What stands out about Humber Summit’s hazards
For Humber Summit, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Humber Summit faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Humber Summit grades A− for hazard risk
Earthquake risk and radon make Humber Summit’s grade; wildfire can only lower it, never raise it, and flood studies are listed but not scored.
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. The burned-area record misses fires under about 10 ha and most grass and farm fires.
Few fires near Humber Summit: 0% within 5 km, 0% within 25 km
Fires mapped since 1986 around where Humber Summit’s residents live, and the fuel next to their homes.
Humber Summit burns at 0.000% a year, low against 0.000% for the typical Canadian town.
Forest makes up 0.6% of the land within 5 km of Humber Summit and 2.2% within 25 km, little for a forest fire to run through.
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 Humber Summit, 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.
Humber Summit 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.
Toronto Regional Conservation Authority has mapped flooding for Humber Summit (1 study)
Flood studies whose area touches Humber Summit, from NRCan’s inventory, each linked to its owner.
The flood study touching Humber Summit 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, Humber Summit 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 Humber Summit.
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.
Earthquakes cost buildings in Humber Summit $0.043 per $1,000 a year
NRCan’s seismic risk model: the damage shaking is expected to do to buildings each year, on average over many years.
At $0.043 per $1,000, Humber Summit’s earthquake risk is about the typical Canadian town’s ($0.030; 1.4 times).
Humber Summit 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
The median in Ontario is $0.043; Humber Summit, 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.
Humber Summit 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).
Only shaking damage to buildings in Humber Summit is counted; landslides, liquefaction, tsunami and fire after a quake aren’t.
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 Humber Summit are over the radon guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline. · Shared with the rest of the City of Toronto Health Unit: radon tests
A lower share than most: 2.7% of tested homes around Humber Summit, the typical Canadian town 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Humber Summit’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.
Under 5% puts Humber Summit with 37% of Canada’s 2,611 towns; 63% have more high tests.
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 low area share in Humber Summit doesn’t clear a house, nor does a high one condemn it: test.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Where to get warnings in Humber Summit
Environment and Climate Change Canada issues the weather alerts for Humber Summit; 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 Humber Summit, 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 Humber Summit’s neighbours compare on hazards
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Humber Summit | Low | $0.043 | 2.7% | Yes |
| Thistletown-Beaumond Heights 9,357 · 1.5 km | Low | $0.043 | 2.7% | Yes |
| Mount Olive-Silverstone-Jamestown 32,069 · 1.8 km | Low | $0.043 | 2.7% | Yes |
| Humbermede 16,959 · 1.9 km | Low | $0.043 | 2.7% | Yes |
| Rexdale-Kipling 10,378 · 3.4 km | Low | $0.043 | 2.7% | Yes |
| Woodbridge 18,835 · 3.5 km | Low | $0.028 | 0% | Yes |
| West Humber-Clairville 33,690 · 3.6 km | Low | $0.043 | 2.7% | Yes |
Thistletown-Beaumond Heights (low) has the heaviest fire record of Humber Summit’s neighbours, and Humber Summit (low) matches or beats it.
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Humber Summit faces
Practical steps for Humber Summit’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
- Earthquakes are modelled. Seismic risk is NRCan’s model of yearly building losses from shaking, averaged over many years and given for Humber Summit’s census subdivision (a neighbourhood shows its city’s).
- Wildfire counts one way. For Humber Summit, wildfire means how much nearby land burned in the past forty years, a one-way input that can pull Risk down and nothing more.
- 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 Humber Summit.
- Radon is a survey. About 14,000 homes were tested across Canada in 2009–2011, and the share over the guideline for Humber Summit is its health region’s, the survey’s design unit.
Questions about flooding and hazards in Humber Summit
Does Humber Summit flood?
There is flood mapping for Humber Summit on the national inventory, each study linked to its owner’s map, none of them graded.
How is Humber Summit’s Hazard risk Grade worked out?
Hazard risk gives Humber Summit A−, weighing earthquakes and radon and counting wildfire only against it.
Is Humber Summit at risk of wildfire?
Very little by the national record: Humber Summit’s band is low, with 0% of the land within 25 km burned since 1986, so wildfire doesn’t change its grade.
How big is the earthquake risk in Humber Summit?
About $0.043 a year per $1,000 of building value, NRCan’s long-run expectation for Humber Summit.
Is radon a problem in Humber Summit?
2.7% of the 74 homes Health Canada tested around Humber Summit topped the guideline; your own house needs its own test.
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).