Photo: Cantons-de-l'Est · CC0Saint-Nazaire’s hazards at a glance: a low wildfire record and 2.8% of area homes over the radon guideline
The national fire record shows next to nothing around Saint-Nazaire, 0% of the land within 25 km since 1986 (0.001% a year). Seismic risk runs high: $0.21 of expected damage per $1,000 of buildings a year, the typical town $0.030. Hazard risk gives Saint-Nazaire a grade of C+, from earthquakes and radon alone.
What stands out about Saint-Nazaire’s hazards
For Saint-Nazaire, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Saint-Nazaire faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Saint-Nazaire grades C+ for hazard risk
Earthquake risk and radon make Saint-Nazaire’s grade; wildfire can only lower it, never raise it, and flood studies are listed but not scored.
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 Saint-Nazaire: 0% within 5 km, 0% within 25 km
Fires mapped since 1986 around where Saint-Nazaire’s residents live, and the fuel next to their homes.
Saint-Nazaire burns at 0.001% a year, low against 0.000% for the typical Canadian town.
No fire has burned within 5 km of Saint-Nazaire’s homes since 1986; the nearest burn is 15 km away.
More forest grows near Saint-Nazaire’s homes (62% within 5 km) than across 25 km (56%).
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
Saint-Nazaire burns at 0.001% a year, 136th of 514 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.
Some fire is mapped around Saint-Nazaire, but not enough to leave the low band, where 92% of Canada’s 2,610 towns are; 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-Nazaire
Flood studies whose area touches Saint-Nazaire, from NRCan’s inventory, each linked to its owner.
NRCan’s inventory is silent on Saint-Nazaire, so any flood map would be the municipality’s own.
Towns with a flood study on file
Only 45% of towns in Quebec have a flood study, short of Canada’s 58%, and Saint-Nazaire is not among them.
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 Saint-Nazaire’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 Saint-Nazaire: $0.21 per $1,000 of buildings a year
NRCan’s seismic risk model: the damage shaking is expected to do to buildings each year, on average over many years.
Saint-Nazaire’s $0.21 is about 6.8 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
The typical town in Quebec expects $0.14 a year; Saint-Nazaire expects $0.21, and La Pocatière $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.
Saint-Nazaire is in the top tenth of Canada’s 2,611 towns for earthquake risk; 8.4% 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).
What a quake does after the shaking, fire, landslides, tsunami, falls outside NRCan’s figure for Saint-Nazaire.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean).
2.8% of homes tested around Saint-Nazaire are over the radon guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline.
A lower share than most: 2.8% of tested homes around Saint-Nazaire, the typical Canadian town 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 Saint-Nazaire 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.
Under 5% puts Saint-Nazaire with 37% of Canada’s 2,611 towns; 63% have more high tests.
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.
Neighbouring homes in Saint-Nazaire can differ a lot; only a long-term test tells you about yours.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011). · Data for radon tests covers the Saguenay - Lac-Saint-Jean health region
Where to get warnings in Saint-Nazaire
Environment and Climate Change Canada issues the weather alerts for Saint-Nazaire; 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 Saint-Nazaire, and listen to local authorities for orders.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How Saint-Nazaire’s neighbours compare on hazards
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Saint-Nazaire | Low | $0.21 | 2.8% | None listed |
| Alma 30,659 · 6.7 km | Low | $0.22 | 2.8% | None listed |
| Labrecque 1,375 · 11 km | Low | $0.18 | 2.8% | None listed |
| Saint-Bruno 2,935 · 13 km | Low | $0.24 | 2.8% | None listed |
| L'Ascension-de-Notre-Seigneur 2,291 · 15 km | Low | $0.19 | 2.8% | None listed |
| Larouche 1,734 · 16 km | Low | $0.20 | 2.8% | None listed |
| Saint-Gédéon 2,349 · 16 km | Low | $0.22 | 2.8% | None listed |
Larouche burns a little more than Saint-Nazaire, in the same low band (low here).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Saint-Nazaire faces
Practical steps for Saint-Nazaire’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?
- 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. The earthquake figure is an expected loss, not a forecast, worked out by NRCan for each census subdivision, Saint-Nazaire’s included.
- 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-Nazaire.
- Radon is a survey. Health Canada’s survey tested some 14,000 homes over three months; until postal-area boundaries are loaded, Saint-Nazaire takes its 2007 health region’s share.
- Wildfire counts one way. Burned land within 25 km of where people live, averaged over 1986–2025 and checked for fuel near homes, is the measure; it looks back, not ahead, and only ever counts against Saint-Nazaire.
Questions about flooding and hazards in Saint-Nazaire
Is Saint-Nazaire at risk of wildfire?
Not much by Canadian standards: Saint-Nazaire’s band is low, with 0% of the land within 25 km burned since 1986 (last in 2023), so wildfire doesn’t change its grade.
How big is the earthquake risk in Saint-Nazaire?
About $0.21 a year per $1,000 of building value, NRCan’s long-run expectation for Saint-Nazaire.
Does Saint-Nazaire flood?
No study on Canada’s Flood Map Inventory covers Saint-Nazaire (0), which doesn’t mean it has never been mapped, so ask the municipality.
How is Saint-Nazaire’s Hazard risk Grade worked out?
Hazard risk gives Saint-Nazaire C+, weighing earthquakes and radon and counting wildfire only against it.
Is radon a problem in Saint-Nazaire?
2.8% of the 72 homes Health Canada tested around Saint-Nazaire topped the guideline; your own house needs its own test.
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).