Photo: Gabriel Picard · CC BY-SA 4.0On hazards, Saint-Antoine-de-Tilly comes out behind 91% of Canadian towns
Wildfire isn’t Saint-Antoine-de-Tilly’s worry: 0% of the land within 25 km burned since 1986 (0.000% a year). Shaking is a bigger worry than in most places, at $0.14 a year per $1,000 of building value ($0.030 typical). In Health Canada’s survey, 13% of homes tested in the area exceeded 200 Bq/m³ (6.6% typical). Hazard risk gives Saint-Antoine-de-Tilly a grade of D, from earthquakes and radon alone.
What stands out about Saint-Antoine-de-Tilly’s hazards
For Saint-Antoine-de-Tilly, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Saint-Antoine-de-Tilly faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Saint-Antoine-de-Tilly grades D for hazard risk
Two inputs always count for Saint-Antoine-de-Tilly, earthquakes and radon; the third, wildfire, counts only against a town.
How sure: The seismic figure is a long-run average from NRCan’s model, not a prediction. The burned-area record misses fires under about 10 ha and most grass and farm fires.
Few fires near Saint-Antoine-de-Tilly: 0% within 5 km, 0% within 25 km
Fires mapped since 1986 around where Saint-Antoine-de-Tilly’s residents live, and the fuel next to their homes.
Forty years of fire maps put Saint-Antoine-de-Tilly at 0.000% a year, low next to the typical Canadian town’s 0.000%.
The 5 km ring around Saint-Antoine-de-Tilly’s homes is clear of burns since 1986, the nearest 23 km out.
There is forest near Saint-Antoine-de-Tilly’s homes (14% within 5 km) and more of it further out (32% 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 514
Near-zero burning puts Saint-Antoine-de-Tilly with 145 of the 514 towns in Quebec, far below Mistissini at 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.
92% of Canada’s 2,610 towns are in the low band and 7.5% above it; Saint-Antoine-de-Tilly is among the many where the yearly burn rate rounds to zero.
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 Saint-Antoine-de-Tilly
Flood studies whose area touches Saint-Antoine-de-Tilly, from NRCan’s inventory, each linked to its owner.
Nationally, Saint-Antoine-de-Tilly has no listed flood study; the municipality is the place to ask.
Towns with a flood study on file
Flood maps are thinner in Quebec, 45% of towns against 58% nationally, and Saint-Antoine-de-Tilly has none.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
Flood mapping is shown for Saint-Antoine-de-Tilly to be opened and checked, never turned into a grade.
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.”
Earthquakes cost buildings in Saint-Antoine-de-Tilly $0.14 per $1,000 a year
NRCan’s seismic risk model: the damage shaking is expected to do to buildings each year, on average over many years.
The typical town loses $0.030 a year to shaking; Saint-Antoine-de-Tilly loses $0.14, 4.5 times as much.
Shaking damage a year per $1,000 of building value
The median in Quebec is $0.14; Saint-Antoine-de-Tilly, at $0.14, is right beside it, and La Pocatière tops the list 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.
Saint-Antoine-de-Tilly sits above most of Canada’s 2,611 towns on earthquake risk; 22% 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 Saint-Antoine-de-Tilly 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).
Radon runs high around Saint-Antoine-de-Tilly: 13% of tested homes over the guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline. · Measured across the Chaudiere-Appalaches health region: radon tests
More homes than usual test high around Saint-Antoine-de-Tilly: 13% against 6.6% for the typical Canadian town.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
More homes top the guideline around Saint-Antoine-de-Tilly (13%) than in the typical town in Quebec (8.2%); 0.6% went over 600.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
The 10–20% band holds 22% of Canada’s 2,611 towns, Saint-Antoine-de-Tilly among them; 4.6% 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.
Neighbouring homes in Saint-Antoine-de-Tilly can differ a lot; only a long-term test tells you about yours.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Where to get warnings in Saint-Antoine-de-Tilly
Alerts for Saint-Antoine-de-Tilly 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 Saint-Antoine-de-Tilly to phones; CWFIS shows the day’s fire danger.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How Saint-Antoine-de-Tilly’s neighbours compare on hazards
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Saint-Antoine-de-Tilly | Low | $0.14 | 13% | None listed |
| Neuville 4,579 · 4.5 km | Low | $0.14 | 8.8% | None listed |
| Saint-Apollinaire 9,218 · 7.6 km | Low | $0.14 | 13% | None listed |
| Donnacona 7,785 · 13 km | Low | $0.11 | 8.8% | None listed |
| Saint-Augustin-de-Desmaures 20,864 · 13 km | Low | $0.12 | 8.8% | None listed |
| Sainte-Croix 2,612 · 14 km | Low | $0.13 | 13% | None listed |
| Laurier-Station 2,838 · 14 km | Low | $0.14 | 13% | None listed |
Neuville burns a little more than Saint-Antoine-de-Tilly, in the same low band (low here).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Saint-Antoine-de-Tilly faces
What to do about the hazards Saint-Antoine-de-Tilly 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
- 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 Saint-Antoine-de-Tilly until then.
- 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 Saint-Antoine-de-Tilly.
- Flood studies aren’t flood zones. Flood studies cover areas of every size, which is why the page lists them for Saint-Antoine-de-Tilly without grading them.
- Earthquakes are modelled. The earthquake figure is an expected loss, not a forecast, worked out by NRCan for each census subdivision, Saint-Antoine-de-Tilly’s included.
Questions about flooding and hazards in Saint-Antoine-de-Tilly
Does Saint-Antoine-de-Tilly flood?
With 0 studies on the inventory, Saint-Antoine-de-Tilly’s flood risk is unmapped nationally; check with the municipality before buying.
Is Saint-Antoine-de-Tilly at risk of wildfire?
Fire has reached 0% of the land around Saint-Antoine-de-Tilly since 1986 (last in 1989); at low, it neither helps nor hurts the grade.
How is Saint-Antoine-de-Tilly’s Hazard risk Grade worked out?
Saint-Antoine-de-Tilly’s Hazard risk grade is D, built on earthquakes and radon with a one-sided wildfire input.
How big is the earthquake risk in Saint-Antoine-de-Tilly?
Expected earthquake damage in Saint-Antoine-de-Tilly comes to $0.14 a year for each $1,000 that buildings are worth.
Is radon a problem in Saint-Antoine-de-Tilly?
Around Saint-Antoine-de-Tilly, 175 survey homes were tested and 13% came in over 200 Bq/m³, a guide to the area, not to any one home.
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).