Photo: P199 · Public domainFlood mapping exists for L'Île-Perrot: 2 on record, latest by Communauté métropolitaine de Montréal
Fire seldom reaches L'Île-Perrot: since 1986, 0.1% of the land within 25 km has burned (0.001% a year). Shaking is a bigger worry than in most places, at $0.16 a year per $1,000 of building value ($0.030 typical). Radon around L'Île-Perrot is ordinary for Canada: 8.2% of tested homes over the guideline (6.6% typical). Hazard risk gives L'Île-Perrot a grade of C, from earthquakes and radon alone.
What stands out about L'Île-Perrot’s hazards
Four national sources, each read for L'Île-Perrot: earthquakes, radon, past fires and flood studies.
What L'Île-Perrot faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in L'Île-Perrot: C
For L'Île-Perrot, Risk will be the average of earthquakes and radon, with wildfire added only if it makes the average worse.
Its place: #283 of 507 in Quebec and #2,239 of 2,589 Canadian towns.
How sure: Earthquake losses are a model’s expectation over many years, not a forecast for any one. Small fires and grass fires are largely missing from the national burned-area record.
Few fires near L'Île-Perrot: 0% within 5 km, 0.1% within 25 km
Fires mapped since 1986 around where L'Île-Perrot’s residents live, and the fuel next to their homes.
L'Île-Perrot burns at 0.001% a year, low against 0.000% for the typical Canadian town.
L'Île-Perrot’s homes have had no fire within 5 km since 1986; the closest was 13 km away.
Land that isn’t forest covers nearly all the ground around L'Île-Perrot: forest fuel is 2% within 5 km and 2.4% 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
L'Île-Perrot 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.
The low band takes in 92% of Canada’s 2,610 towns, L'Île-Perrot 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.
L'Île-Perrot is on the flood map inventory: 2 studies, latest by Communauté métropolitaine de Montréal
Flood studies whose area touches L'Île-Perrot, from NRCan’s inventory, each linked to its owner.
2 studies on the inventory touch L'Île-Perrot, the newest Communauté métropolitaine de Montréal’s from 2008, and their areas can be large, so they say maps exist, not that the town floods.
| Study | By | Year | Status |
|---|---|---|---|
| Montréal-Argenteuil-Deux-Montagnes-Vaudreuil-Soulanges | Communauté métropolitaine de Montréal | 2008 | final |
| St-Louis-Varennes | Gouvernement du Québec | 1977 | final |
Towns with a flood study on file
L'Île-Perrot is one of the 45% of towns in Quebec with a flood study on file, fewer than Canada’s 58%.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
No single decade dominates: 2 studies for L'Île-Perrot between the 1970s and the 2000s.
Study dates as the NRCan inventory lists them, one count per study touching L'Île-Perrot.
Listed, not scored: a flood study proves a map exists, not that L'Île-Perrot 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.”
Natural Resources Canada, Canada Flood Map Inventory; links go to each study’s owner.
Shaking is L'Île-Perrot’s costliest hazard: $0.16 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.
Roughly 5.3 times the typical $0.030: L'Île-Perrot’s $0.16 marks real seismic exposure.
Shaking damage a year per $1,000 of building value
Shaking damage around L'Île-Perrot runs at $0.16 a year, near the $0.14 of the typical town in Quebec; La Pocatière has $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.
15% of Canada’s 2,611 towns expect more shaking damage than L'Île-Perrot, which places it in the upper third.
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 L'Île-Perrot’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).
8.2% of homes tested around L'Île-Perrot are over the radon guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline. · The radon tests numbers here cover the Monteregie health region
L'Île-Perrot’s area, at 8.2%, is close to the 6.6% of the typical Canadian town.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
L'Île-Perrot’s area, at 8.2%, is close to the median in Quebec (8.2%).
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Between 5% and 10% of tests over the guideline: L'Île-Perrot, and 37% of Canada’s 2,611 towns; 26% 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.
Basements, soil and how a house is sealed decide its radon, so in L'Île-Perrot only a test can say.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Weather and fire alerts for L'Île-Perrot
Alerts for L'Île-Perrot 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. |
Alert Ready carries evacuation orders for L'Île-Perrot to phones; CWFIS shows the day’s fire danger.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
Hazards in the places around L'Île-Perrot
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| L'Île-Perrot | Low | $0.16 | 8.2% | Yes |
| Pincourt 15,220 · 2.5 km | Low | $0.17 | 8.2% | Yes |
| Sainte-Anne-de-Bellevue 5,393 · 2.5 km | Low | $0.17 | 6.8% | Yes |
| Terrasse-Vaudreuil 1,883 · 2.6 km | Low | $0.19 | 8.2% | Yes |
| Senneville 1,042 · 2.9 km | Low | $0.15 | 6.8% | Yes |
| Notre-Dame-de-l'Île-Perrot 11,716 · 3.2 km | Low | $0.14 | 8.2% | Yes |
| Baie-D'Urfé 3,706 · 4.4 km | Low | $0.16 | 6.8% | Yes |
The neighbour with the most fire is Pincourt (low), still no more than L'Île-Perrot (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what L'Île-Perrot faces
Practical steps for L'Île-Perrot’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?
- Check the address on the flood map.
- Are flood and wildfire insured?
- Is earthquake cover included?
What this data can and can’t tell you
- 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 L'Île-Perrot’s.
- Wildfire counts one way. The wildfire figure is the share of land within 25 km of L'Île-Perrot’s homes burned each year from 1986 to 2025, past fire rather than a forecast, and it can only lower Risk.
- 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 L'Île-Perrot.
- Radon is a survey. Health Canada’s survey tested some 14,000 homes over three months; until postal-area boundaries are loaded, L'Île-Perrot takes its 2007 health region’s share.
Questions about flooding and hazards in L'Île-Perrot
Is L'Île-Perrot at risk of wildfire?
Some, but L'Île-Perrot’s low band (0.1% of nearby land burned since 1986, latest 2025) is short of the level that counts.
Is radon a problem in L'Île-Perrot?
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 L'Île-Perrot.
Does L'Île-Perrot flood?
The inventory lists a study touching L'Île-Perrot; whether a given street floods is on that map, not in the grade.
How big is the earthquake risk in L'Île-Perrot?
Expected earthquake damage in L'Île-Perrot comes to $0.16 a year for each $1,000 that buildings are worth.
How is L'Île-Perrot’s Hazard risk Grade worked out?
L'Île-Perrot grades C for hazard risk, from earthquakes and radon, with wildfire counted only where it lowers the grade.
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).