Photo: Wilson Hui from Calgary, Canada · CC BY 2.0Hazards in Trochu: wildfire low, radon over the guideline in 7.5% of tested homes
Wildfire barely registers for Trochu, at 0% of the land within 25 km since 1986 (0.000% a year). Shaking is less of a worry than in most places, at $0.013 a year per $1,000 of building value ($0.030 typical). Hazard risk gives Trochu a grade of A−, from earthquakes and radon alone.
What stands out about Trochu’s hazards
For Trochu, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Trochu faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Trochu: A−
Two inputs always count for Trochu, earthquakes and radon; the third, wildfire, counts only against a town.
How sure: Earthquake losses are a model’s expectation over many years, not a forecast for any one. The burned-area record misses fires under about 10 ha and most grass and farm fires.
Little of the land around Trochu has burned: 0% within 5 km, 0% within 25 km since 1986
Fires mapped since 1986 around where Trochu’s residents live, and the fuel next to their homes.
Low by Canadian standards: 0.000% of the land a year around Trochu, 0.000% for the typical Canadian town.
Only 0.1% of the land within 25 km of Trochu is forest fuel, and 0% 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 Alberta · highest of 479
Fire has taken almost none of the land around Trochu, as for 387 of the 479 towns in Alberta; Wainwright tops the list at 1.43%.
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.
Like most of Canada’s 2,610 towns (92%), Trochu is in the low band, with a burn rate of zero to three decimals; 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 Trochu
Flood studies whose area touches Trochu, from NRCan’s inventory, each linked to its owner.
Canada’s Flood Map Inventory lists no study whose area touches Trochu, which doesn’t mean it has never been mapped.
Towns with a flood study on file
Flood maps are thinner in Alberta, 46% of towns against 58% nationally, and Trochu 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 Trochu.
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 Trochu just $0.013 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.
Trochu’s $0.013 is a fraction of the typical town’s $0.030 (0.4 times as much): quiet ground by Canadian standards.
Shaking damage a year per $1,000 of building value
Neither high nor low in Alberta: Trochu’s $0.013 sits by the median of $0.013, while Black Diamond reaches $0.048.
NRCan seismic risk model (2022): mean yearly building loss per $1,000 of value; medians of towns of 2,500 people or more.
Trochu is in the lower part of Canada’s range for earthquake risk; 75% of the 2,611 towns 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 Trochu 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).
Some radon around Trochu: 7.5% of area homes over the guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline.
The survey area of Trochu reads 7.5%, a shade from the typical Canadian town’s 6.6%. For radon tests, the only official count covers all of the David Thompson Regional Health Authority, Trochu included.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Radon around Trochu is ordinary for towns in Alberta: 7.5%, beside a median of 7.5%.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Trochu is in the 5–10% band with 37% of Canada’s 2,611 towns; 26% have more.
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 low area share in Trochu doesn’t clear a house, nor does a high one condemn it: test.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Where to get warnings in Trochu
Alerts for Trochu 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. |
Evacuation orders for Trochu come from the municipality or the province, while CWFIS maps fire danger every day.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How Trochu’s neighbours compare on hazards
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Trochu | Low | $0.013 | 7.5% | None listed |
| Kneehill County 5,129 · 13 km | Low | $0.014 | 7.5% | Yes |
| Three Hills 3,502 · 14 km | Low | $0.012 | 7.5% | None listed |
Nowhere around Trochu burns more: Kneehill County, the closest rival, is low to its low.
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Trochu faces
What to do about the hazards Trochu 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.
- 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
- 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 Trochu.
- Radon is a survey. About 14,000 homes were tested across Canada in 2009–2011, and the share over the guideline for Trochu is its health region’s, the survey’s design unit.
- Earthquakes are modelled. The earthquake figure is an expected loss, not a forecast, worked out by NRCan for each census subdivision, Trochu’s included.
- 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 Trochu.
Questions about flooding and hazards in Trochu
Is Trochu at risk of wildfire?
The burned-area record shows next to nothing around Trochu (0% within 25 km since 1986), so its band is low.
How big is the earthquake risk in Trochu?
Expected earthquake damage in Trochu comes to $0.013 a year for each $1,000 that buildings are worth.
Is radon a problem in Trochu?
In Health Canada’s survey, 7.5% of 107 homes tested in Trochu’s area were above 200 Bq/m³, though only a test tells you about one house.
Does Trochu flood?
Nothing is listed for Trochu on the national inventory (0); local maps may still exist with the municipality.
How is Trochu’s Hazard risk Grade worked out?
Trochu grades A− 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).