Photo: Pymouss · CC BY-SA 4.0Hazards in Mont-Royal: wildfire low, radon over the guideline in 6.8% of tested homes
Burn scars are few around Mont-Royal, with 0.1% 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 $0.22 a year per $1,000 of building value ($0.030 typical). Mont-Royal grades C for hazard risk; wildfire is low here, so it earns no credit.
What stands out about Mont-Royal’s hazards
Four national sources, each read for Mont-Royal: earthquakes, radon, past fires and flood studies.
What Mont-Royal faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Mont-Royal grades C for hazard risk
The grade weighs Mont-Royal’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: #240 of 507 in Quebec and #2,189 of 2,589 Canadian towns.
How sure: Earthquake losses are a model’s expectation over many years, not a forecast for any one. The radon share rests on 74 home tests in the survey area, so a few homes move it. Small fires and grass fires are largely missing from the national burned-area record.
Little of the land around Mont-Royal has burned: 0% within 5 km, 0.1% within 25 km since 1986
Past fire around Mont-Royal’s homes, from the national burned-area record, with the fuel within 5 km.
Mont-Royal burns at 0.001% a year, low against 0.000% for the typical Canadian town.
The closest burn since 1986 lies 12 km from Mont-Royal’s homes, none within 5 km.
Only 0.7% of the land within 25 km of Mont-Royal is forest fuel, and 0.1% close in.
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
Mont-Royal 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.
The low band takes in 92% of Canada’s 2,610 towns, Mont-Royal among them, though its rate is above zero; 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 Mont-Royal
What Canada’s Flood Map Inventory lists for Mont-Royal: who studied flooding and where to see their maps.
NRCan’s inventory is silent on Mont-Royal, so any flood map would be the municipality’s own.
Towns with a flood study on file
Flood maps are thinner in Quebec, 45% of towns against 58% nationally, and Mont-Royal has none.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
Nothing here counts toward Risk; the studies are pointers to the maps their owners keep for Mont-Royal.
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 Mont-Royal’s costliest hazard: $0.22 a year per $1,000
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
At $0.22 per $1,000, Mont-Royal carries roughly 7.3 times the typical Canadian town’s earthquake risk ($0.030).
Shaking damage a year per $1,000 of building value
Earthquake risk in Quebec peaks in La Pocatière ($0.48); Mont-Royal, at $0.22, 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.
Mont-Royal is in the top tenth of Canada’s 2,611 towns for earthquake risk; 7.4% 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).
The loss is to Mont-Royal’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).
Some radon around Mont-Royal: 6.8% of area homes over the guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline. · Shared with the rest of the Montreal health region: radon tests
At 6.8% over the guideline, the area around Mont-Royal is about level with the typical Canadian town’s 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
The typical town in Quebec has 8.2% over 200 Bq/m³; Mont-Royal’s area has 6.8%, much the same.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
A middling share of high tests puts Mont-Royal with 37% of Canada’s 2,611 towns, below 26% of them.
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.
The survey sampled homes around Mont-Royal; it can’t tell you your basement’s level.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Weather and fire alerts for Mont-Royal
Environment and Climate Change Canada issues the weather alerts for Mont-Royal; 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 Mont-Royal, and listen to local authorities for orders.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How Mont-Royal’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 |
|---|---|---|---|---|
| Mont-Royal | Low | $0.22 | 6.8% | None listed |
| Parc-Kent 27,291 · 1.6 km | Low | $0.20 | 6.8% | None listed |
| Parc-Extension 29,066 · 1.9 km | Low | $0.20 | 6.8% | None listed |
| Savane 32,028 · 2.1 km | Low | $0.20 | 6.8% | None listed |
| Chameran/Montpellier 21,170 · 2.6 km | Low | $0.20 | 6.8% | None listed |
| Outremont 24,629 · 2.7 km | Low | $0.20 | 6.8% | None listed |
| Édouard-Montpetit 20,601 · 2.8 km | Low | $0.20 | 6.8% | None listed |
The fire record around Outremont is a touch heavier than Mont-Royal’s, but the band is the same: low (here low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Mont-Royal faces
What to do about the hazards Mont-Royal 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
- Wildfire counts one way. Wildfire is read from the national burned-area record around Mont-Royal’s homes since 1986, a history of fire that may lower Risk but never raises it.
- Earthquakes are modelled. NRCan models what earthquakes would cost buildings each year on average, subdivision by subdivision; Mont-Royal’s figure is its subdivision’s.
- Radon is a survey. About 14,000 homes were tested across Canada in 2009–2011, and the share over the guideline for Mont-Royal is its health region’s, the survey’s design unit.
- Flood studies aren’t flood zones. NRCan’s inventory says where flood mapping exists, not where water goes; the map’s owner is the authority for Mont-Royal.
Questions about flooding and hazards in Mont-Royal
Does Mont-Royal flood?
Nothing is listed for Mont-Royal on the national inventory (0); local maps may still exist with the municipality.
How big is the earthquake risk in Mont-Royal?
In NRCan’s seismic model, Mont-Royal’s buildings lose $0.22 per $1,000 of value in an average year.
How is Mont-Royal’s Hazard risk Grade worked out?
Mont-Royal grades C for hazard risk, from earthquakes and radon, with wildfire counted only where it lowers the grade.
Is radon a problem in Mont-Royal?
In Health Canada’s survey, 6.8% of 74 homes tested in Mont-Royal’s area were above 200 Bq/m³, though only a test tells you about one house.
Is Mont-Royal at risk of wildfire?
Less than most of Canada: 0.1% of the land within 25 km of Mont-Royal has burned since 1986, the last in 2025, a low band that leaves Risk alone.
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).