Photo: Khayman · CC BY-SA 3.0Sainte-Thérèse faces more hazards than 89% of Canadian towns
Burn scars are few around Sainte-Thérèse, with 0% of the land within 25 km touched by fire since 1986 (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). More homes than usual carry radon here, 10% over the guideline where the typical town has 6.6%. Sainte-Thérèse grades D for hazard risk; wildfire is low here, so it earns no credit.
What stands out about Sainte-Thérèse’s hazards
Four national sources, each read for Sainte-Thérèse: earthquakes, radon, past fires and flood studies.
What Sainte-Thérèse faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Sainte-Thérèse grades D for hazard risk
Seismic risk and radon set Sainte-Thérèse’s grade, wildfire can drag it down, and flood mapping stays out of it.
Its place: #470 of 507 in Quebec and #2,471 of 2,589 Canadian towns.
How sure: The seismic figure is a long-run average from NRCan’s model, not a prediction. Only 78 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.
Little of the land around Sainte-Thérèse has burned: 0% within 5 km, 0% within 25 km since 1986
Fires mapped since 1986 around where Sainte-Thérèse’s residents live, and the fuel next to their homes.
The yearly burn rate around Sainte-Thérèse is 0.001%, low beside 0.000% for the typical Canadian town.
6.7% of the land within 25 km of Sainte-Thérèse is forest fuel, yet only 3.5% within 5 km of its homes.
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
Sainte-Thérèse sits mid-table in Quebec: 136th of 513 towns, at 0.001% a year, well behind Mistissini (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 Sainte-Thérèse, 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.
The flood map inventory lists nothing for Sainte-Thérèse
Flood studies whose area touches Sainte-Thérèse, from NRCan’s inventory, each linked to its owner.
NRCan’s inventory is silent on Sainte-Thérèse, so any flood map would be the municipality’s own.
Towns with a flood study on file
No study touches Sainte-Thérèse; in Quebec, 45% of towns have one, below Canada’s 58%.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
Flood studies don’t enter the grade; they are listed so you can open the official map for Sainte-Thérèse.
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-Thérèse’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.
Sainte-Thérèse’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
Sainte-Thérèse’s $0.20 tops the median in Quebec, $0.14, though 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.
Sainte-Thérèse sits above most of Canada’s 2,611 towns on earthquake risk; 12% 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 Sainte-Thérèse’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).
Test for radon in Sainte-Thérèse: 10% of area homes were over the guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline.
Sainte-Thérèse’s area, at 10%, is above the 6.6% of the typical Canadian town, so testing is worth more here than most places.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
More homes top the guideline around Sainte-Thérèse (10%) than in the typical town in Quebec (8.2%); 1.3% went over 600.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Sainte-Thérèse is in the 10–20% band, with 22% of Canada’s 2,611 towns; only 4.6% are 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.
One home in Sainte-Thérèse can be high while next door is low; a three-month test settles it.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011). · Radon tests: the Laurentides health region
Weather and fire alerts for Sainte-Thérèse
Alerts for Sainte-Thérèse 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-Thérèse 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-Thérèse’s neighbours compare on hazards
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Sainte-Thérèse | Low | $0.20 | 10% | None listed |
| Boisbriand 29,830 · 3.3 km | Low | $0.20 | 10% | Yes |
| Rosemère 14,198 · 3.6 km | Low | $0.16 | 10% | Yes |
| Blainville 61,739 · 3.8 km | Low | $0.19 | 10% | None listed |
| Lorraine 9,721 · 5.4 km | Low | $0.18 | 10% | Yes |
| Sainte-Rose 37,408 · 6.5 km | Low | $0.21 | 12% | Yes |
| Bois-des-Filion 10,666 · 6.9 km | Low | $0.13 | 10% | Yes |
Boisbriand (low) has the heaviest fire record of Sainte-Thérèse’s neighbours, and Sainte-Thérèse (low) matches or beats it.
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Sainte-Thérèse faces
Practical steps for Sainte-Thérèse’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
- Flood studies aren’t flood zones. Flood studies cover areas of every size, which is why the page lists them for Sainte-Thérèse without grading them.
- Earthquakes are modelled. NRCan models what earthquakes would cost buildings each year on average, subdivision by subdivision; Sainte-Thérèse’s figure is its subdivision’s.
- Radon is a survey. Radon figures pool the survey’s home tests by area: postal areas once their boundaries arrive, the 2007 health region around Sainte-Thérèse until then.
- Wildfire counts one way. Wildfire is read from the national burned-area record around Sainte-Thérèse’s homes since 1986, a history of fire that may lower Risk but never raises it.
Questions about flooding and hazards in Sainte-Thérèse
Is radon a problem in Sainte-Thérèse?
10% of the 78 homes Health Canada tested around Sainte-Thérèse topped the guideline; your own house needs its own test.
Does Sainte-Thérèse flood?
No study on Canada’s Flood Map Inventory covers Sainte-Thérèse (0), which doesn’t mean it has never been mapped, so ask the municipality.
How big is the earthquake risk in Sainte-Thérèse?
Expected earthquake damage in Sainte-Thérèse comes to $0.20 a year for each $1,000 that buildings are worth.
Is Sainte-Thérèse at risk of wildfire?
Not much by Canadian standards: Sainte-Thérèse’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.
How is Sainte-Thérèse’s Hazard risk Grade worked out?
Sainte-Thérèse’s Hazard risk grade is D, built on earthquakes and radon with a one-sided wildfire input.
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).