Photo: Calvin411 · CC BY-SA 4.0Hazards in Grenet: wildfire low, radon over the guideline in 6.8% of tested homes
Little of the land around Grenet has burned: 0.1% within 25 km since 1986, or 0.001% a year. Earthquakes add more: NRCan’s model puts building losses at $0.20 a year per $1,000 of value, against $0.030 for the typical town. Grenet grades C for hazard risk; wildfire is low here, so it earns no credit.
What stands out about Grenet’s hazards
Four national sources, each read for Grenet: earthquakes, radon, past fires and flood studies.
What Grenet faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Grenet: C
The grade weighs Grenet’s seismic risk and radon equally, and wildfire is one-sided: a high band counts against a town, a low one earns nothing.
Its place: #161 of 507 in Quebec and #2,110 of 2,589 Canadian towns.
How sure: The seismic figure is a long-run average from NRCan’s model, not a prediction. The radon share rests on 74 home tests in the survey area, so a few homes move it. Small fires and grass fires are largely missing from the national burned-area record.
Wildfire is rare near Grenet: 0.1% of the land within 25 km burned since 1986, 0% within 5 km
Past fire around Grenet’s homes, from the national burned-area record, with the fuel within 5 km.
Low: the land around Grenet burns at 0.001% a year, where the typical Canadian town sees 0.000%.
The closest burn since 1986 lies 14 km from Grenet’s homes, none within 5 km.
Forest fuel is scarce around Grenet: 0.4% of the land within 5 km, 1.3% 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 Quebec · highest of 513
At 0.001% a year, Grenet ranks 136th of the 513 towns in Quebec; Mistissini leads at 0.31%.
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.
Grenet is in the low band with 92% of Canada’s 2,610 towns; 7.5% sit in moderate or 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.
The flood map inventory lists nothing for Grenet
What Canada’s Flood Map Inventory lists for Grenet: who studied flooding and where to see their maps.
NRCan’s inventory is silent on Grenet, so any flood map would be the municipality’s own.
Towns with a flood study on file
No study touches Grenet; in Quebec, 45% of towns have one, below Canada’s 58%.
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 Grenet’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.”
Shaking is Grenet’s costliest hazard: $0.20 a year per $1,000
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
At $0.20 per $1,000, Grenet carries roughly 6.7 times the typical Canadian town’s earthquake risk ($0.030).
Shaking damage a year per $1,000 of building value
Above the middle in Quebec: Grenet’s $0.20 against a median of $0.14, with La Pocatière highest at $0.48.
NRCan seismic risk model (2022): mean yearly building loss per $1,000 of value; medians of towns of 2,500 people or more.
Grenet is in the top tenth of Canada’s 2,611 towns for earthquake risk; 8.5% rank 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).
The loss is to Grenet’s buildings alone, from ground shaking; infrastructure and secondary hazards are left out.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean). · Earthquake risk: one figure for all of the city of Montréal
6.8% of homes tested around Grenet are over the radon guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline. · Radon tests for the Montreal health region
Grenet’s area sits close to the typical Canadian town: 6.8% over the guideline, against 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
The typical town in Quebec has 8.2% over 200 Bq/m³; Grenet’s area has 6.8%, much the same.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
A middling share of high tests puts Grenet with 37% of Canada’s 2,611 towns, below 26% of them.
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 Grenet only a test can say.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Weather and fire alerts for Grenet
Environment and Climate Change Canada issues the weather alerts for Grenet; 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. |
Smoke and fire warnings for Grenet come through Environment Canada and Alert Ready; the fire map is CWFIS’s.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
Hazards in the places around Grenet
Wildfire band, earthquake risk, radon and flood studies for each place nearby.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Grenet | Low | $0.20 | 6.8% | None listed |
| Dutrisac 10,643 · 0.9 km | Low | $0.20 | 6.8% | None listed |
| Du College/Hodge 22,329 · 1.8 km | Low | $0.20 | 6.8% | None listed |
| Chameran/Montpellier 21,170 · 1.8 km | Low | $0.20 | 6.8% | None listed |
| Nouveau-Bordeaux 30,171 · 1.8 km | Low | $0.20 | 6.8% | None listed |
| Bois-Francs 35,858 · 1.8 km | Low | $0.20 | 6.8% | None listed |
| Cartierville 24,617 · 2.0 km | Low | $0.20 | 6.8% | None listed |
Nowhere around Grenet burns more: Dutrisac, 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 Grenet faces
What to do about the hazards Grenet 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.
- Drop, cover and hold on.
- Strap the water heater down.
- Keep 72 hours of supplies.
- Has it had a radon test?
- Ask the municipality for flood maps.
- Are flood and wildfire insured?
- Is earthquake cover included?
What this data can and can’t tell you
- Wildfire counts one way. Wildfire is read from the national burned-area record around Grenet’s homes since 1986, a history of fire that may lower Risk but never raises it.
- Earthquakes are modelled. NRCan models what earthquakes would cost buildings each year on average, subdivision by subdivision; Grenet’s figure is its subdivision’s.
- 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 Grenet 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 Grenet floods.
Questions about flooding and hazards in Grenet
Is radon a problem in Grenet?
In Health Canada’s survey, 6.8% of 74 homes tested in Grenet’s area were above 200 Bq/m³, though only a test tells you about one house.
How is Grenet’s Hazard risk Grade worked out?
Hazard risk gives Grenet C, weighing earthquakes and radon and counting wildfire only against it.
Does Grenet flood?
Nothing is listed for Grenet on the national inventory (0); local maps may still exist with the municipality.
Is Grenet at risk of wildfire?
Less than most of Canada: 0.1% of the land within 25 km of Grenet has burned since 1986, the last in 2025, a low band that leaves Risk alone.
How big is the earthquake risk in Grenet?
NRCan’s model expects shaking to cost buildings in Grenet $0.20 a year for every $1,000 of their value, on average over many years.
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).