Photo: SamuelFreli · CC BY-SA 3.0Cowansville’s hazards at a glance: a low wildfire record and 8.2% of area homes over the radon guideline
Wildfire barely registers for Cowansville, at 0% of the land within 25 km since 1986 (0.000% a year). Earthquakes add more: NRCan’s model puts building losses at $0.089 a year per $1,000 of value, against $0.030 for the typical town. Hazard risk gives Cowansville a grade of C+, from earthquakes and radon alone.
What stands out about Cowansville’s hazards
Four national sources, each read for Cowansville: earthquakes, radon, past fires and flood studies.
What Cowansville faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Cowansville: C+
For Cowansville, Risk will be the average of earthquakes and radon, with wildfire added only if it makes the average worse.
Its place: #121 of 507 in Quebec and #2,005 of 2,589 Canadian towns.
How sure: The seismic figure is a long-run average from NRCan’s model, not a prediction. Small fires and grass fires are largely missing from the national burned-area record.
Little of the land around Cowansville has burned: 0% within 5 km, 0% within 25 km since 1986
Past fire around Cowansville’s homes, from the national burned-area record, with the fuel within 5 km.
A burn rate of 0.000% a year keeps Cowansville in the low band (the typical Canadian town: 0.000%).
Since 1986 the nearest fire to Cowansville’s homes came within 17 km, never inside 5 km.
Forest fuel is denser close to Cowansville (17% within 5 km) than further out (10% 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
Of the 513 towns in Quebec, 144 have a burn rate that rounds to zero, Cowansville among them; Mistissini leads at 0.31% a year.
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.
Measured against 2,610 towns, Cowansville is in the largest group, low (92%), and at its floor, while 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 Cowansville
What Canada’s Flood Map Inventory lists for Cowansville: who studied flooding and where to see their maps.
An empty entry for Cowansville on the inventory isn’t proof of safety; ask locally for flood maps.
Towns with a flood study on file
Flood maps are thinner in Quebec, 45% of towns against 58% nationally, and Cowansville has none.
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 Cowansville.
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 Cowansville: $0.089 per $1,000 of buildings a year
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
Roughly 3 times the typical $0.030: Cowansville’s $0.089 marks real seismic exposure.
Shaking damage a year per $1,000 of building value
At $0.089, Cowansville 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.
Cowansville sits above most of Canada’s 2,611 towns on earthquake risk; 27% 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).
Roads, pipes and bridges aren’t in Cowansville’s figure, nor landslides or tsunami: it is buildings and shaking.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean).
Some radon around Cowansville: 8.2% of area homes over the guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline.
The survey area of Cowansville reads 8.2%, a shade from the typical Canadian town’s 6.6%. Nobody publishes radon tests for Cowansville alone, so this card uses the figure for the Monteregie health region.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Around Cowansville, 8.2% of tests topped the guideline, about the same as 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.
Radon tops the guideline in a modest share of homes around Cowansville, a band holding 37% of Canada’s 2,611 towns; 26% 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 survey sample isn’t a map: any home in Cowansville 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).
Weather and fire alerts for Cowansville
Alerts for Cowansville 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 Cowansville 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)
Hazards in the places around Cowansville
Wildfire band, earthquake risk, radon and flood studies for each place nearby.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Cowansville | Low | $0.089 | 8.2% | None listed |
| Brigham 2,386 · 6.2 km | Low | $0.099 | 8.2% | Yes |
| Dunham 3,632 · 6.7 km | Low | $0.072 | 8.2% | None listed |
| Bromont 12,413 · 13 km | Low | $0.067 | 8.2% | Yes |
| Saint-Alphonse-de-Granby 3,545 · 13 km | Low | $0.10 | 8.2% | None listed |
| Sutton 4,775 · 16 km | Low | $0.045 | 8.2% | None listed |
| Lac-Brome 6,307 · 17 km | Low | $0.051 | 8.2% | None listed |
Brigham (low) has the heaviest fire record of Cowansville’s neighbours, and Cowansville (low) matches or beats it.
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Cowansville faces
Practical steps for Cowansville’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.
- 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
- Radon is a survey. The radon share comes from about 14,000 long-term home tests in 2009–2011, pooled for now by the 2007 health region Cowansville sits in.
- Wildfire counts one way. The wildfire figure is the share of land within 25 km of Cowansville’s homes burned each year from 1986 to 2025, past fire rather than a forecast, and it can only lower Risk.
- Earthquakes are modelled. Shaking damage is modelled from the ground, the buildings and the odds of each quake, and published for whole subdivisions such as Cowansville’s.
- Flood studies aren’t flood zones. A study’s area can be a whole watershed or province, so being on the inventory says a map exists, not that a home in Cowansville floods.
Questions about flooding and hazards in Cowansville
How is Cowansville’s Hazard risk Grade worked out?
Hazard risk gives Cowansville C+, weighing earthquakes and radon and counting wildfire only against it.
Is Cowansville at risk of wildfire?
Some, but Cowansville’s low band (0% of nearby land burned since 1986, latest 2025) is short of the level that counts.
Is radon a problem in Cowansville?
The area’s survey found 8.2% of 110 tested homes above Health Canada’s guideline, so a three-month test is worth doing in Cowansville.
How big is the earthquake risk in Cowansville?
NRCan’s model expects shaking to cost buildings in Cowansville $0.089 a year for every $1,000 of their value, on average over many years.
Does Cowansville flood?
The inventory has 0 studies for Cowansville, and an empty list isn’t a clean bill: the municipality holds any flood maps.
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).