Photo: Mario Roy · CC BY 3.0Hazards in Sainte-Justine: wildfire low, radon over the guideline in 13% of tested homes
Since 1986 almost nothing has burned near Sainte-Justine: 0% of the land within 25 km, or 0.000% a year. Seismic risk runs high: $0.062 of expected damage per $1,000 of buildings a year, the typical town $0.030. Sainte-Justine grades C− for hazard risk; wildfire is low here, so it earns no credit.
What stands out about Sainte-Justine’s hazards
For Sainte-Justine, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Sainte-Justine faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Sainte-Justine: C−
Two inputs always count for Sainte-Justine, earthquakes and radon; the third, wildfire, counts only against a town.
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.
Wildfire is rare near Sainte-Justine: 0% of the land within 25 km burned since 1986, 0% within 5 km
Past fire around Sainte-Justine’s homes, from the national burned-area record, with the fuel within 5 km.
At 0.000% of the land a year, Sainte-Justine’s burn rate is in the low band; the typical Canadian town sees 0.000%.
Sainte-Justine’s homes have had no fire within 5 km since 1986; the closest was 11 km away.
Forest fuel is spread evenly around Sainte-Justine: 77% within 5 km, 77% 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 514
Fire has taken almost none of the land around Sainte-Justine, as for 145 of the 514 towns in Quebec; Mistissini tops the list 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.
Like most of Canada’s 2,610 towns (92%), Sainte-Justine 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.
No flood study is listed for Sainte-Justine
What Canada’s Flood Map Inventory lists for Sainte-Justine: who studied flooding and where to see their maps.
Canada’s Flood Map Inventory lists no study whose area touches Sainte-Justine, which doesn’t mean it has never been mapped.
Towns with a flood study on file
Sainte-Justine has no flood study on file; only 45% of towns in Quebec do, against 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 Sainte-Justine 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.”
Shaking is Sainte-Justine’s costliest hazard: $0.062 a year per $1,000
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
The typical town loses $0.030 a year to shaking; Sainte-Justine loses $0.062, 2.1 times as much.
Shaking damage a year per $1,000 of building value
At $0.062, Sainte-Justine is below the typical town in Quebec ($0.14); La Pocatière is 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.
More earthquake risk than most: only 29% of Canada’s 2,611 towns are above Sainte-Justine.
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 Sainte-Justine 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).
Test for radon in Sainte-Justine: 13% of area homes were 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 Chaudiere-Appalaches health region
Radon runs above the typical Canadian town (6.6%) in Sainte-Justine’s area, at 13%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Around Sainte-Justine, 13% of tests were over 200 Bq/m³ and 0.6% over 600, against a median of 8.2% in Quebec.
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, Sainte-Justine 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.
A low area share in Sainte-Justine 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 Sainte-Justine
Alerts for Sainte-Justine 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. |
Fire danger and active fires near Sainte-Justine are mapped daily by the Canadian Wildland Fire Information System; evacuation orders come from the municipality or province.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How Sainte-Justine’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 |
|---|---|---|---|---|
| Sainte-Justine | Low | $0.062 | 13% | None listed |
| Lac-Etchemin 4,089 · 11 km | Low | $0.052 | 13% | Yes |
Sainte-Justine’s low band tops its neighbours; Lac-Etchemin is next (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Sainte-Justine faces
What to do about the hazards Sainte-Justine 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?
- Ask the municipality for flood maps.
- 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 Sainte-Justine’s census subdivision (a neighbourhood shows its city’s).
- Radon is a survey. About 14,000 homes were tested across Canada in 2009–2011, and the share over the guideline for Sainte-Justine is its health region’s, the survey’s design unit.
- Wildfire counts one way. For Sainte-Justine, 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 Sainte-Justine.
Questions about flooding and hazards in Sainte-Justine
Is Sainte-Justine at risk of wildfire?
Fire has reached 0% of the land around Sainte-Justine since 1986 (last in 2020); at low, it neither helps nor hurts the grade.
How big is the earthquake risk in Sainte-Justine?
NRCan’s model expects shaking to cost buildings in Sainte-Justine $0.062 a year for every $1,000 of their value, on average over many years.
How is Sainte-Justine’s Hazard risk Grade worked out?
Sainte-Justine grades C− for hazard risk, from earthquakes and radon, with wildfire counted only where it lowers the grade.
Is radon a problem in Sainte-Justine?
Around Sainte-Justine, 175 survey homes were tested and 13% came in over 200 Bq/m³, a guide to the area, not to any one home.
Does Sainte-Justine flood?
With 0 studies on the inventory, Sainte-Justine’s flood risk is unmapped nationally; check with the municipality before buying.
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).