Photo: Vintotal · CC BY-SA 3.0Wildfire low, radon 2.8%: how Mashteuiatsh stands on hazards
Wildfire is rare near Mashteuiatsh: 0.1% of the land within 25 km has burned since 1986, a burn rate of 0.003% a year. Shaking is a bigger worry than in most places, at $0.13 a year per $1,000 of building value ($0.030 typical). Mashteuiatsh grades B for hazard risk, with wildfire counted against it.
What stands out about Mashteuiatsh’s hazards
For Mashteuiatsh, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Mashteuiatsh faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Mashteuiatsh: B
Two inputs always count for Mashteuiatsh, 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. Only 72 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 Mashteuiatsh: 0% within 5 km, 0.1% within 25 km
Past fire around Mashteuiatsh’s homes, from the national burned-area record, with the fuel within 5 km.
Forty years of fire maps put Mashteuiatsh at 0.003% a year, low next to the typical Canadian town’s 0.000%.
The closest burn since 1986 lies 13 km from Mashteuiatsh’s homes, none within 5 km.
Within 5 km of Mashteuiatsh, 14% of the land is forest fuel; widen the ring to 25 km and it is 61%.
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
In the top quarter in Quebec: Mashteuiatsh ranks 32nd of 514 at 0.003% a year, with Mistissini first 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.
Low, like 92% of the country’s 2,610 towns: the land around Mashteuiatsh burns, but slower than in the 7.5% above it.
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 Mashteuiatsh
What Canada’s Flood Map Inventory lists for Mashteuiatsh: who studied flooding and where to see their maps.
The inventory has nothing for Mashteuiatsh, but a local or conservation-authority map may still exist.
Towns with a flood study on file
Mashteuiatsh 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 is shown here, never graded: a study says where a map exists, not how many of Mashteuiatsh’s homes stand in a flood zone.
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.”
High seismic risk in Mashteuiatsh: $0.13 per $1,000 of buildings a year
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
The typical town loses $0.030 a year to shaking; Mashteuiatsh loses $0.13, 4.4 times as much.
Shaking damage a year per $1,000 of building value
Neither high nor low in Quebec: Mashteuiatsh’s $0.13 sits by the median of $0.14, while La Pocatière reaches $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.
In the upper part of Canada’s range: 22% of its 2,611 towns expect more damage than Mashteuiatsh.
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).
What a quake does after the shaking, fire, landslides, tsunami, falls outside NRCan’s figure for Mashteuiatsh.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean).
Little radon around Mashteuiatsh: 2.8% of area homes 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 Saguenay - Lac-Saint-Jean health region
At 2.8% over the guideline, the area around Mashteuiatsh is under the typical Canadian town’s 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Below the typical town in Quebec (8.2%) at 2.8%, the area around Mashteuiatsh still had 1.4% of tests over 600 Bq/m³.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
The quietest radon band, under 5%, holds 37% of Canada’s 2,611 towns and Mashteuiatsh; 63% sit higher.
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 Mashteuiatsh 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 Mashteuiatsh
Environment and Climate Change Canada issues the weather alerts for Mashteuiatsh; 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. |
In fire season, check CWFIS for danger and active fires around Mashteuiatsh, and listen to local authorities for orders.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How Mashteuiatsh’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 |
|---|---|---|---|---|
| Mashteuiatsh | Low | $0.13 | 2.8% | None listed |
| Roberval 9,828 · 6.9 km | Low | $0.13 | 2.8% | Yes |
| Saint-Prime 2,808 · 7.7 km | Low | $0.16 | 2.8% | Yes |
| Saint-Félicien 10,143 · 17 km | Low | $0.13 | 2.8% | Yes |
The neighbour with the most fire is Roberval (low), still no more than Mashteuiatsh (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Mashteuiatsh faces
What to do about the hazards Mashteuiatsh 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
- Earthquakes are modelled. Seismic risk is NRCan’s model of yearly building losses from shaking, averaged over many years and given for Mashteuiatsh’s census subdivision (a neighbourhood shows its city’s).
- Radon is a survey. Health Canada’s survey tested some 14,000 homes over three months; until postal-area boundaries are loaded, Mashteuiatsh takes its 2007 health region’s share.
- Wildfire counts one way. For Mashteuiatsh, 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. The flood inventory points to maps; it is incomplete and not the official source, so ask the municipality about any street in Mashteuiatsh.
Questions about flooding and hazards in Mashteuiatsh
Is Mashteuiatsh at risk of wildfire?
Fire has reached 0.1% of the land around Mashteuiatsh since 1986 (last in 2009); at low, it neither helps nor hurts the grade.
Is radon a problem in Mashteuiatsh?
Around Mashteuiatsh, 72 survey homes were tested and 2.8% came in over 200 Bq/m³, a guide to the area, not to any one home.
How big is the earthquake risk in Mashteuiatsh?
NRCan’s model expects shaking to cost buildings in Mashteuiatsh $0.13 a year for every $1,000 of their value, on average over many years.
Does Mashteuiatsh flood?
With 0 studies on the inventory, Mashteuiatsh’s flood risk is unmapped nationally; check with the municipality before buying.
How is Mashteuiatsh’s Hazard risk Grade worked out?
Hazard risk gives Mashteuiatsh B, weighing earthquakes and radon and counting wildfire only against it.
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).