Carrville Corners faces fewer hazards than 90% of Canadian towns
Around Carrville Corners, wildfire is practically absent from the record: 0% within 25 km since 1986, 0.000% a year. Earthquake risk in Carrville Corners is ordinary: NRCan’s model puts building losses at $0.028 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%. Hazard risk gives Carrville Corners a grade of A, from earthquakes and radon alone.
What stands out about Carrville Corners’s hazards
For Carrville Corners, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Carrville Corners faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Carrville Corners grades A for hazard risk
Seismic risk and radon set Carrville Corners’ 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. The burned-area record misses fires under about 10 ha and most grass and farm fires.
Few fires near Carrville Corners: 0% within 5 km, 0% within 25 km
Past fire around Carrville Corners’ homes, from the national burned-area record, with the fuel within 5 km.
Next to the typical Canadian town (0.000% a year), Carrville Corners’ 0.000% is in the low band.
Land that isn’t forest covers nearly all the ground around Carrville Corners: forest fuel is 0.7% within 5 km and 3.9% 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
Near-zero burning puts Carrville Corners with 638 of the 871 towns in Ontario, far below Sioux Lookout 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.
Like most of Canada’s 2,610 towns (92%), Carrville Corners is in the low band, with a burn rate of zero to three decimals; 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.
Carrville Corners is on the flood map inventory: 1 study, by Toronto Regional Conservation Authority
What Canada’s Flood Map Inventory lists for Carrville Corners: who studied flooding and where to see their maps.
For Carrville Corners 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, Carrville Corners 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 mapping is shown for Carrville Corners to be opened and checked, never turned into a grade.
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 Carrville Corners: $0.028 a year per $1,000
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
With $0.028 of shaking damage a year per $1,000, Carrville Corners is about even with the typical $0.030 (0.9 times).
Nobody publishes earthquake risk for Carrville Corners alone, so this card uses the figure for the city of Vaughan.
Shaking damage a year per $1,000 of building value
Below the middle in Ontario: Carrville Corners’ $0.028 against a median of $0.043; Alexandria has $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.
Neither high nor low for Canada: 51% of the 2,611 towns expect more damage than Carrville Corners.
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 Carrville Corners 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).
Radon runs low around Carrville Corners: 0% of tested homes over the guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline.
Where the typical Canadian town has 6.6% of homes over the guideline, Carrville Corners’ area has fewer, 0%. Carrville Corners doesn’t get its own radon tests figures; the ones here come from the York Regional Health Unit.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
The median in Ontario is 4% over 200 Bq/m³; around Carrville Corners it is 0%.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Under 5% puts Carrville Corners 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.
Radon varies from house to house in Carrville Corners, so the survey is a reason to test, not a result for yours.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Where to get warnings in Carrville Corners
Alerts for Carrville Corners 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. |
Evacuation orders for Carrville Corners come from the municipality or the province, while CWFIS maps fire danger every day.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
Hazards in the places around Carrville Corners
Wildfire band, earthquake risk, radon and flood studies for each place nearby.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Carrville Corners | Low | $0.028 | 0% | Yes |
| Dufferin Hill 7,910 · 1.7 km | Low | $0.028 | 0% | Yes |
| The Valleys of Thornhill 9,979 · 2.0 km | Low | $0.028 | 0% | Yes |
| Maple 20,122 · 2.0 km | Low | $0.028 | 0% | Yes |
| Thornhill Woods 13,237 · 2.7 km | Low | $0.028 | 0% | Yes |
| Upper Thornhill Estates 10,435 · 2.9 km | Low | $0.028 | 0% | Yes |
| Crossroads 4,525 · 3.1 km | Low | $0.028 | 0% | Yes |
Nowhere around Carrville Corners burns more: Dufferin Hill, the closest rival, is low to its low.
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Carrville Corners faces
Practical steps for Carrville Corners’ 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
- 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 Carrville Corners.
- Wildfire counts one way. For Carrville Corners, wildfire means how much nearby land burned in the past forty years, a one-way input that can pull Risk down and nothing more.
- Radon is a survey. About 14,000 homes were tested across Canada in 2009–2011, and the share over the guideline for Carrville Corners is its health region’s, the survey’s design unit.
- Earthquakes are modelled. Seismic risk is NRCan’s model of yearly building losses from shaking, averaged over many years and given for Carrville Corners’ census subdivision (a neighbourhood shows its city’s).
Questions about flooding and hazards in Carrville Corners
Is radon a problem in Carrville Corners?
The area’s survey found 0% of 95 tested homes above Health Canada’s guideline, so a three-month test is worth doing in Carrville Corners.
How is Carrville Corners’s Hazard risk Grade worked out?
Carrville Corners’ Hazard risk grade is A, built on earthquakes and radon with a one-sided wildfire input.
Does Carrville Corners flood?
There is flood mapping for Carrville Corners on the national inventory, each study linked to its owner’s map, none of them graded.
Is Carrville Corners at risk of wildfire?
Very little by the national record: Carrville Corners’ 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 Carrville Corners?
In NRCan’s seismic model, Carrville Corners’ buildings lose $0.028 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).