Photo: Earth Science and Remote Sensing Unit , Lyndon B. Johnson Space Center · Public domainLethbridge County is on Canada’s flood inventory: 1 listed, led by Government of Alberta
Burn scars are few around Lethbridge County, with 1.1% of the land within 25 km touched by fire since 1986 (0.03% a year). Shaking is about as much of a worry in Lethbridge County as in most places, at $0.024 a year per $1,000 of building value ($0.030 typical). Lethbridge County’s survey area, 8.9% over the radon guideline, is close to the typical town’s 6.6%. Lethbridge County grades B for hazard risk, with wildfire counted against it.
What stands out about Lethbridge County’s hazards
Four national sources, each read for Lethbridge County: earthquakes, radon, past fires and flood studies.
What Lethbridge County faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Lethbridge County grades B for hazard risk
For Lethbridge County, Risk will be the average of earthquakes and radon, with wildfire added only if it makes the average worse.
Its place: #448 of 474 in Alberta and #1,506 of 2,589 Canadian towns.
How sure: The seismic figure is a long-run average from NRCan’s model, not a prediction. Small fires and grass fires are largely missing from the national burned-area record.
Few fires near Lethbridge County: 1.5% within 5 km, 1.1% within 25 km
Fires mapped since 1986 around where Lethbridge County’s residents live, and the fuel next to their homes.
Lethbridge County burns at 0.03% a year, low against 0.000% for the typical Canadian town.
Forest makes up 0.1% of the land within 5 km of Lethbridge County and 0% within 25 km, little for a forest fire to run through.
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 478
In the top quarter in Alberta: Lethbridge County ranks 44th of 478 at 0.03% a year, with Wainwright first 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.
The low band takes in 92% of Canada’s 2,610 towns, Lethbridge County 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.
Government of Alberta has mapped flooding for Lethbridge County (1 study)
Flood studies whose area touches Lethbridge County, from NRCan’s inventory, each linked to its owner.
The flood study touching Lethbridge County is Government of Alberta’s, dated 2007; its own map shows the zones street by street.
| Study | By | Year | Status |
|---|---|---|---|
| Lethbridge Flood Hazard Study | Government of Alberta | 2007 | final |
Towns with a flood study on file
Its flood study sets Lethbridge County apart in Alberta, where 46% of towns have one (Canada: 58%).
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 Lethbridge County.
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.
Expected shaking damage in Lethbridge County: $0.024 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.
At $0.024 per $1,000, Lethbridge County’s earthquake risk is about the typical Canadian town’s ($0.030; 0.8 times).
Shaking damage a year per $1,000 of building value
Lethbridge County’s $0.024 tops the median in Alberta, $0.013, though 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.
Lethbridge County sits mid-range among Canada’s 2,611 towns: 54% expect more shaking damage.
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 Lethbridge County’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).
8.9% of homes tested around Lethbridge County are over the radon guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline.
Near the middle for radon: Lethbridge County’s area 8.9%, the typical Canadian town 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
0.9% of tests around Lethbridge County passed 600 Bq/m³; over 200, its 8.9% matches the median in Alberta, 7.5%.
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: Lethbridge County, 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.
A survey sample isn’t a map: any home in Lethbridge County can be high, and a three-month test is the only way to know.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011). · Radon tests: one figure for all of the Chinook Regional Health Authority
Weather and fire alerts for Lethbridge County
Environment and Climate Change Canada issues the weather alerts for Lethbridge County; 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 Lethbridge County, and listen to local authorities for orders.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
Hazards in the places around Lethbridge County
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Lethbridge County | Low | $0.024 | 8.9% | Yes |
| Picture Butte 2,380 · 3.8 km | Low | $0.023 | 8.9% | None listed |
| Coalhurst 3,244 · 15 km | Moderate | $0.029 | 8.9% | None listed |
| Lethbridge 113,671 · 18 km | Moderate | $0.025 | 8.9% | Yes |
| Coaldale 9,644 · 18 km | Low | $0.027 | 8.9% | None listed |
| Nobleford 1,694 · 19 km | Moderate | $0.026 | 8.9% | None listed |
The heaviest fire record nearby is Coalhurst’s, moderate to Lethbridge County’s low.
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Lethbridge County faces
Practical steps for Lethbridge County’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.
- Clear needles and wood nearby.
- Keep a grab-and-go bag ready.
- In smoke, stay in; filter air.
- Has it had a radon test?
- Check the address on the flood map.
- Are flood and wildfire insured?
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 Lethbridge County’s.
- 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 Lethbridge County sits in.
- 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 Lethbridge County floods.
- Wildfire counts one way. The wildfire figure is the share of land within 25 km of Lethbridge County’s homes burned each year from 1986 to 2025, past fire rather than a forecast, and it can only lower Risk.
Questions about flooding and hazards in Lethbridge County
How big is the earthquake risk in Lethbridge County?
Expected earthquake damage in Lethbridge County comes to $0.024 a year for each $1,000 that buildings are worth.
Is radon a problem in Lethbridge County?
8.9% of the 112 homes Health Canada tested around Lethbridge County topped the guideline; your own house needs its own test.
Does Lethbridge County flood?
Lethbridge County’s area has been studied for flooding, and the owner’s map shows which streets lie in a zone; the grade leaves flood out.
Is Lethbridge County at risk of wildfire?
Not much by Canadian standards: Lethbridge County’s band is low, with 1.1% of the land within 25 km burned since 1986 (last in 2021), so wildfire doesn’t change its grade.
How is Lethbridge County’s Hazard risk Grade worked out?
Lethbridge County’s Hazard risk grade is B, built on earthquakes and radon with a one-sided wildfire input.
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).