Photo: P199 · CC BY-SA 4.0Boisbriand faces more hazards than 89% of Canadian towns
Little of the land around Boisbriand has burned: 0% within 25 km since 1986, or 0.001% a year. Shaking is a bigger worry than in most places, at $0.20 a year per $1,000 of building value ($0.030 typical). In Health Canada’s survey, 10% of homes tested in the area exceeded 200 Bq/m³ (6.6% typical). Hazard risk gives Boisbriand a grade of D, from earthquakes and radon alone.
What stands out about Boisbriand’s hazards
Four national sources, each read for Boisbriand: earthquakes, radon, past fires and flood studies.
What Boisbriand faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Boisbriand: D
Earthquake risk and radon make Boisbriand’s grade; wildfire can only lower it, never raise it, and flood studies are listed but not scored.
Its place: #469 of 507 in Quebec and #2,469 of 2,589 Canadian towns.
How sure: Earthquake losses are a model’s expectation over many years, not a forecast for any one. The radon share rests on 78 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.
Little of the land around Boisbriand has burned: 0% within 5 km, 0% within 25 km since 1986
Fires mapped since 1986 around where Boisbriand’s residents live, and the fuel next to their homes.
In a typical year 0.001% of the land near Boisbriand burns; the typical Canadian town sees 0.000%, and both are low.
Homes in Boisbriand sit on open or built-up ground (2.6% forest fuel within 5 km); the wider 25 km holds 6%.
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, Boisbriand 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.
Boisbriand 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.
Gouvernement du Québec has mapped flooding for Boisbriand (1 study)
Flood studies whose area touches Boisbriand, from NRCan’s inventory, each linked to its owner.
For Boisbriand the inventory points to Gouvernement du Québec’s 2006 study, whose map is the one to check.
| Study | By | Year | Status |
|---|---|---|---|
| Moulins-Thérèse-De-Blainville-Deux-Montagnes-Laval | Gouvernement du Québec | 2006 | final |
Towns with a flood study on file
Flood maps are thinner in Quebec, 45% of towns against 58% nationally, but Boisbriand has one.
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 Boisbriand 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.
Shaking is Boisbriand’s costliest hazard: $0.20 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.
Boisbriand’s $0.20 is about 6.6 times the typical town’s $0.030: it sits in one of Canada’s more active seismic zones.
Shaking damage a year per $1,000 of building value
At $0.20, Boisbriand is above the typical town in Quebec ($0.14); La Pocatière has the most 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.
12% of Canada’s 2,611 towns expect more shaking damage than Boisbriand, which places it in the upper third.
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 Boisbriand’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).
Radon runs high around Boisbriand: 10% of tested homes over the guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline.
More homes than usual test high around Boisbriand: 10% against 6.6% for the typical Canadian town.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Boisbriand’s area, at 10%, is above the median in Quebec (8.2%), and 1.3% of its tests passed 600 Bq/m³.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
The 10–20% band holds 22% of Canada’s 2,611 towns, Boisbriand among them; 4.6% rank above.
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 Boisbriand only a test can say.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011). · Area behind the radon tests figures: the Laurentides health region
Weather and fire alerts for Boisbriand
Alerts for Boisbriand 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 Boisbriand 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)
How Boisbriand’s neighbours compare on hazards
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Boisbriand | Low | $0.20 | 10% | Yes |
| Sainte-Thérèse 27,253 · 3.3 km | Low | $0.20 | 10% | None listed |
| Rosemère 14,198 · 4.9 km | Low | $0.16 | 10% | Yes |
| Fabreville 48,457 · 5.2 km | Low | $0.21 | 12% | Yes |
| Sainte-Rose 37,408 · 5.3 km | Low | $0.21 | 12% | Yes |
| Saint-Eustache 47,562 · 6.4 km | Low | $0.20 | 10% | Yes |
| Blainville 61,739 · 6.7 km | Low | $0.19 | 10% | None listed |
Among its neighbours Boisbriand has the most fire on record (low); Sainte-Thérèse follows (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Boisbriand faces
Practical steps for Boisbriand’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.
- Drop, cover and hold on.
- Strap the water heater down.
- Keep 72 hours of supplies.
- Has it had a radon test?
- Check the address on the flood map.
- Are flood and wildfire insured?
- Is earthquake cover included?
What this data can and can’t tell you
- Wildfire counts one way. The wildfire figure is the share of land within 25 km of Boisbriand’s homes burned each year from 1986 to 2025, past fire rather than a forecast, and it can only lower Risk.
- 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 Boisbriand.
- Earthquakes are modelled. Shaking damage is modelled from the ground, the buildings and the odds of each quake, and published for whole subdivisions such as Boisbriand’s.
- Radon is a survey. About 14,000 homes were tested across Canada in 2009–2011, and the share over the guideline for Boisbriand is its health region’s, the survey’s design unit.
Questions about flooding and hazards in Boisbriand
Is radon a problem in Boisbriand?
10% of the 78 homes Health Canada tested around Boisbriand topped the guideline; your own house needs its own test.
Is Boisbriand at risk of wildfire?
Not much by Canadian standards: Boisbriand’s band is low, with 0% of the land within 25 km burned since 1986 (last in 2025), so wildfire doesn’t change its grade.
Does Boisbriand flood?
There is flood mapping for Boisbriand on the national inventory, each study linked to its owner’s map, none of them graded.
How is Boisbriand’s Hazard risk Grade worked out?
Hazard risk gives Boisbriand D, weighing earthquakes and radon and counting wildfire only against it.
How big is the earthquake risk in Boisbriand?
Expected earthquake damage in Boisbriand comes to $0.20 a year for each $1,000 that buildings are worth.
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).