Photo: U.S. Embassy and Consulates in Canada · Public domainOn hazards, Thompson comes out behind 97% of Canadian towns
Fire is a regular visitor: 16% of the land within 25 km of Thompson has burned since 1986 (0.40% a year). Seismic risk runs low: $0.004 of expected damage per $1,000 of buildings a year, the typical town $0.030. Radon is about average around Thompson: 7.9% of tested homes in the survey area topped the guideline, against 6.6% for the typical town. Thompson grades D− for hazard risk, with wildfire counted against it.
What stands out about Thompson’s hazards
For Thompson, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Thompson faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Thompson grades D− for hazard risk
Two inputs always count for Thompson, earthquakes and radon; the third, wildfire, counts only against a town.
Its place: #183 of 185 in Manitoba and #2,557 of 2,589 Canadian towns.
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.
Fire country: 16% of the land within 25 km of Thompson has burned since 1986, 7.8% within 5 km
Fires mapped since 1986 around where Thompson’s residents live, and the fuel next to their homes.
The yearly burn rate around Thompson is 0.40%, against 0.000% for the typical Canadian town: the high band.
78% of the land within 5 km of Thompson is forest fuel, close to the 81% 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 Manitoba · highest of 189
The land around Thompson burns at 0.40% a year, the 3rd highest rate of 189 towns in Manitoba; Flin Flon (Part) tops it at 1.68%.
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.
Just 1.9% of Canada’s 2,610 towns burn fast enough for the high band where Thompson sits; 0.2% burn faster.
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 Thompson
Flood studies whose area touches Thompson, from NRCan’s inventory, each linked to its owner.
Nationally, Thompson has no listed flood study; the municipality is the place to ask.
Towns with a flood study on file
Only 18% of towns in Manitoba have a flood study, short of Canada’s 58%, and Thompson is not among them.
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 Thompson.
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.”
Low seismic risk in Thompson: $0.004 per $1,000 of buildings a year
NRCan’s seismic risk model: the damage shaking is expected to do to buildings each year, on average over many years.
0.1 times the typical $0.030: Thompson’s $0.004 is low for Canada.
Shaking damage a year per $1,000 of building value
At $0.004, Thompson is below the typical town in Manitoba ($0.006); Virden is highest at $0.007.
NRCan seismic risk model (2022): mean yearly building loss per $1,000 of value; medians of towns of 2,500 people or more.
At the bottom of Canada’s range, Thompson has 98% of the 2,611 towns above it.
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).
What a quake does after the shaking, fire, landslides, tsunami, falls outside NRCan’s figure for Thompson.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean).
7.9% of homes tested around Thompson are over the radon guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline. · Area-wide: radon tests, counted over the Burntwood/Churchill health region
Around Thompson, 7.9% of tested homes topped the guideline, near the typical Canadian town’s 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Around Thompson, 7.9% of tests were over 200 Bq/m³, under the median in Manitoba (12%); 0.7% were over 600.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
26% of Canada’s 2,611 towns have more homes over 200 Bq/m³ than Thompson’s 5–10% band, which holds 37%.
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, Thompson’s included, whatever the area’s figure.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Where to get warnings in Thompson
Alerts for Thompson 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 Thompson to phones; CWFIS shows the day’s fire danger.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
Get ready for what Thompson faces
What to do about the hazards Thompson faces, and what to ask before you buy.
- Clear needles and wood nearby.
- Keep a grab-and-go bag ready.
- In smoke, stay in; filter air.
- 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.
- Has it had a radon test?
- Ask the municipality for flood maps.
- How close is the forest edge?
- Are flood and wildfire insured?
What this data can and can’t tell you
- 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 Thompson 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 Thompson floods.
- Earthquakes are modelled. The earthquake figure is an expected loss, not a forecast, worked out by NRCan for each census subdivision, Thompson’s included.
- 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 Thompson.
Questions about flooding and hazards in Thompson
Is radon a problem in Thompson?
Around Thompson, 152 survey homes were tested and 7.9% came in over 200 Bq/m³, a guide to the area, not to any one home.
Does Thompson flood?
With 0 studies on the inventory, Thompson’s flood risk is unmapped nationally; check with the municipality before buying.
Is Thompson at risk of wildfire?
More than most Canadian towns; Thompson’s high band rests on 16% of nearby land burned since 1986 (most recently 2025).
How big is the earthquake risk in Thompson?
About $0.004 a year per $1,000 of building value, NRCan’s long-run expectation for Thompson.
How is Thompson’s Hazard risk Grade worked out?
Hazard risk gives Thompson D−, weighing earthquakes and radon and counting wildfire only against it.
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).