Photo: Providence Doucet providence · CC0Flood mapping exists for Crabtree: 2 on record, latest by Gouvernement du Québec
Fire seldom reaches Crabtree: since 1986, 0.1% of the land within 25 km has burned (0.001% a year). Seismic risk runs high: $0.16 of expected damage per $1,000 of buildings a year, the typical town $0.030. Fewer homes than usual carry radon here, 3.9% over the guideline where the typical town has 6.6%. Hazard risk gives Crabtree a grade of B−, from earthquakes and radon alone.
What stands out about Crabtree’s hazards
For Crabtree, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Crabtree faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Crabtree grades B− for hazard risk
For Crabtree, Risk will be the average of earthquakes and radon, with wildfire added only if it makes the average worse.
Its place: #95 of 507 in Quebec and #1,717 of 2,589 Canadian towns.
How sure: The seismic figure is a long-run average from NRCan’s model, not a prediction. Only 77 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.
Little of the land around Crabtree has burned: 0% within 5 km, 0.1% within 25 km since 1986
Past fire around Crabtree’s homes, from the national burned-area record, with the fuel within 5 km.
Low by Canadian standards: 0.001% of the land a year around Crabtree, 0.000% for the typical Canadian town.
Nothing inside 5 km of Crabtree’s homes has burned since 1986, and the nearest scar is 8.1 km off.
Homes in Crabtree sit on open or built-up ground (3.4% forest fuel within 5 km); the wider 25 km holds 9.2%.
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
Crabtree 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.
Some fire is mapped around Crabtree, 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.
Flooding around Crabtree is mapped in 2 studies, the newest by Gouvernement du Québec
What Canada’s Flood Map Inventory lists for Crabtree: who studied flooding and where to see their maps.
Gouvernement du Québec and others have studied flooding in areas that include Crabtree: 2 studies, the latest from 2006.
Towns with a flood study on file
Flood maps are thinner in Quebec, 45% of towns against 58% nationally, but Crabtree has one.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
The grade leaves flood out, since a study area says nothing about how many of Crabtree’s homes are at risk.
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 Crabtree’s costliest hazard: $0.16 a year per $1,000
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
Crabtree’s $0.16 is about 5.3 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
Shaking damage around Crabtree 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.
Crabtree sits above most of Canada’s 2,611 towns on earthquake risk; 15% 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).
Only shaking damage to buildings in Crabtree is counted; landslides, liquefaction, tsunami and fire after a quake aren’t.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean).
Little radon around Crabtree: 3.9% of area homes over the guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline.
Radon runs below the typical Canadian town (6.6%) in Crabtree’s area, at 3.9%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Radon runs lower around Crabtree than in most towns in Quebec: 3.9% against 8.2%.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Under 5% puts Crabtree 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.
Health Canada advises testing every home, Crabtree’s included, whatever the area’s figure.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011). · Radon tests: one figure for all of the Lanaudiere health region
Where to get warnings in Crabtree
Environment and Climate Change Canada issues the weather alerts for Crabtree; 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. |
Smoke and fire warnings for Crabtree come through Environment Canada and Alert Ready; the fire map is CWFIS’s.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How Crabtree’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 |
|---|---|---|---|---|
| Crabtree | Low | $0.16 | 3.9% | Yes |
| Saint-Paul 7,208 · 4.0 km | Low | $0.17 | 3.9% | Yes |
| Sainte-Marie-Salomé 1,296 · 5.1 km | Low | $0.18 | 3.9% | None listed |
| Joliette 22,408 · 6.3 km | Low | $0.17 | 3.9% | Yes |
| Saint-Liguori 2,268 · 7.4 km | Low | $0.16 | 3.9% | None listed |
| Saint-Jacques 4,830 · 7.4 km | Low | $0.16 | 3.9% | None listed |
| Saint-Charles-Borromée 16,904 · 8.9 km | Low | $0.16 | 3.9% | Yes |
The neighbour with the most fire is Saint-Paul (low), still no more than Crabtree (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Crabtree faces
Practical steps for Crabtree’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
- 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 Crabtree floods.
- Earthquakes are modelled. The earthquake figure is an expected loss, not a forecast, worked out by NRCan for each census subdivision, Crabtree’s included.
- 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 Crabtree sits in.
- 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 Crabtree.
Questions about flooding and hazards in Crabtree
Is radon a problem in Crabtree?
3.9% of the 77 homes Health Canada tested around Crabtree topped the guideline; your own house needs its own test.
Is Crabtree at risk of wildfire?
Not much by Canadian standards: Crabtree’s band is low, with 0.1% of the land within 25 km burned since 1986 (last in 2025), so wildfire doesn’t change its grade.
How is Crabtree’s Hazard risk Grade worked out?
Crabtree grades B− for hazard risk, from earthquakes and radon, with wildfire counted only where it lowers the grade.
How big is the earthquake risk in Crabtree?
NRCan’s model expects shaking to cost buildings in Crabtree $0.16 a year for every $1,000 of their value, on average over many years.
Does Crabtree flood?
Crabtree’s area has been studied for flooding, and the owner’s map shows which streets lie in a zone; the grade leaves flood out.
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).