Photo: Vintotal · CC BY-SA 3.0Saint-Roch-de-l'Achigan’s hazards at a glance: a low wildfire record and 3.9% of area homes over the radon guideline
Fire seldom reaches Saint-Roch-de-l'Achigan: since 1986, 0% of the land within 25 km has burned (0.001% a year). Shaking is a bigger worry than in most places, at $0.18 a year per $1,000 of building value ($0.030 typical). Saint-Roch-de-l'Achigan grades C+ for hazard risk; wildfire is low here, so it earns no credit.
What stands out about Saint-Roch-de-l'Achigan’s hazards
Four national sources, each read for Saint-Roch-de-l'Achigan: earthquakes, radon, past fires and flood studies.
What Saint-Roch-de-l'Achigan faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Saint-Roch-de-l'Achigan: C+
The grade weighs Saint-Roch-de-l'Achigan’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: #110 of 507 in Quebec and #1,810 of 2,589 Canadian towns.
How sure: Earthquake losses are a model’s expectation over many years, not a forecast for any one. Only 77 homes were tested in the survey area, so the radon share is rough. Small fires and grass fires are largely missing from the national burned-area record.
Few fires near Saint-Roch-de-l'Achigan: 0% within 5 km, 0% within 25 km
Past fire around Saint-Roch-de-l'Achigan’s homes, from the national burned-area record, with the fuel within 5 km.
The land within 25 km of Saint-Roch-de-l'Achigan burns at 0.001% a year on average, the low band; the typical Canadian town: 0.000%.
Near or far, forest fuel covers a similar share around Saint-Roch-de-l'Achigan: 8.5% within 5 km and 8.5% 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
Saint-Roch-de-l'Achigan burns at 0.001% a year, 136th of 513 towns in Quebec; the leader, Mistissini, reaches 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.
Beside 2,610 Canadian towns, Saint-Roch-de-l'Achigan reads low, with 92% of them; only 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 Saint-Roch-de-l'Achigan
What Canada’s Flood Map Inventory lists for Saint-Roch-de-l'Achigan: who studied flooding and where to see their maps.
No flood study on the national inventory covers Saint-Roch-de-l'Achigan; ask the municipality, which is the authority for its flood maps.
Towns with a flood study on file
Saint-Roch-de-l'Achigan 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.
Listed, not scored: a flood study proves a map exists, not that Saint-Roch-de-l'Achigan 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.”
High seismic risk in Saint-Roch-de-l'Achigan: $0.18 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; Saint-Roch-de-l'Achigan loses $0.18, 6.1 times as much.
Shaking damage a year per $1,000 of building value
Earthquake risk in Quebec peaks in La Pocatière ($0.48); Saint-Roch-de-l'Achigan, at $0.18, sits above the median of $0.14.
NRCan seismic risk model (2022): mean yearly building loss per $1,000 of value; medians of towns of 2,500 people or more.
Saint-Roch-de-l'Achigan sits above most of Canada’s 2,611 towns on earthquake risk; 13% are 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 Saint-Roch-de-l'Achigan’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).
Little radon around Saint-Roch-de-l'Achigan: 3.9% of area homes over the guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline.
A lower share than most: 3.9% of tested homes around Saint-Roch-de-l'Achigan, the typical Canadian town 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Fewer homes top the guideline around Saint-Roch-de-l'Achigan (3.9%) than in the typical town in Quebec (8.2%).
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 Saint-Roch-de-l'Achigan; 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 survey sample isn’t a map: any home in Saint-Roch-de-l'Achigan can be high, and a three-month test is the only way to know.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011). · Area behind the radon tests figures: the Lanaudiere health region
Weather and fire alerts for Saint-Roch-de-l'Achigan
Alerts for Saint-Roch-de-l'Achigan 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 Saint-Roch-de-l'Achigan 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 Saint-Roch-de-l'Achigan’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 |
|---|---|---|---|---|
| Saint-Roch-de-l'Achigan | Low | $0.18 | 3.9% | None listed |
| Saint-Esprit 2,313 · 7.8 km | Low | $0.17 | 3.9% | Yes |
| L'Épiphanie 9,254 · 7.9 km | Low | $0.19 | 3.9% | Yes |
| Sainte-Marie-Salomé 1,296 · 12 km | Low | $0.18 | 3.9% | None listed |
| Saint-Jacques 4,830 · 12 km | Low | $0.16 | 3.9% | None listed |
| Mascouche 56,897 · 12 km | Low | $0.19 | 3.9% | Yes |
| Saint-Alexis 1,462 · 12 km | Low | $0.17 | 3.9% | None listed |
Among its neighbours Saint-Roch-de-l'Achigan has the most fire on record (low); Saint-Esprit follows (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Saint-Roch-de-l'Achigan faces
What to do about the hazards Saint-Roch-de-l'Achigan 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
- Radon is a survey. Health Canada’s survey tested some 14,000 homes over three months; until postal-area boundaries are loaded, Saint-Roch-de-l'Achigan takes its 2007 health region’s share.
- Earthquakes are modelled. NRCan models what earthquakes would cost buildings each year on average, subdivision by subdivision; Saint-Roch-de-l'Achigan’s figure is its subdivision’s.
- Wildfire counts one way. Wildfire is read from the national burned-area record around Saint-Roch-de-l'Achigan’s homes since 1986, a history of fire that may lower Risk but never raises it.
- 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 Saint-Roch-de-l'Achigan.
Questions about flooding and hazards in Saint-Roch-de-l'Achigan
Is radon a problem in Saint-Roch-de-l'Achigan?
Around Saint-Roch-de-l'Achigan, 77 survey homes were tested and 3.9% came in over 200 Bq/m³, a guide to the area, not to any one home.
How is Saint-Roch-de-l'Achigan’s Hazard risk Grade worked out?
Hazard risk gives Saint-Roch-de-l'Achigan C+, weighing earthquakes and radon and counting wildfire only against it.
Is Saint-Roch-de-l'Achigan at risk of wildfire?
Fire has reached 0% of the land around Saint-Roch-de-l'Achigan since 1986 (last in 2025); at low, it neither helps nor hurts the grade.
Does Saint-Roch-de-l'Achigan flood?
With 0 studies on the inventory, Saint-Roch-de-l'Achigan’s flood risk is unmapped nationally; check with the municipality before buying.
How big is the earthquake risk in Saint-Roch-de-l'Achigan?
In NRCan’s seismic model, Saint-Roch-de-l'Achigan’s buildings lose $0.18 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).