Photo: Veillg1 · CC0Wildfire low, radon 6.1%: how Casselman stands on hazards
The burned-area map is nearly blank around Casselman, 0% within 25 km since 1986, 0.000% a year. Shaking is a bigger worry than in most places, at $0.20 a year per $1,000 of building value ($0.030 typical). Casselman grades C for hazard risk; wildfire is low here, so it earns no credit.
What stands out about Casselman’s hazards
Four national sources, each read for Casselman: earthquakes, radon, past fires and flood studies.
What Casselman faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Casselman grades C for hazard risk
Two inputs always count for Casselman, earthquakes and radon; the third, wildfire, counts only against a town.
Its place: #827 of 866 in Ontario and #2,059 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 Casselman: 0% within 5 km, 0% within 25 km
Past fire around Casselman’s homes, from the national burned-area record, with the fuel within 5 km.
Low: the land around Casselman burns at 0.000% a year, where the typical Canadian town sees 0.000%.
6.6% of the land within 25 km of Casselman is forest fuel, yet only 3.5% within 5 km of its homes.
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 Ontario · highest of 871
To three decimals the burn rate around Casselman is zero, as for 638 of the 871 towns in Ontario, while Sioux Lookout reaches 0.16%.
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.
Measured against 2,610 towns, Casselman is in the largest group, low (92%), and at its floor, while 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.
The flood map inventory lists nothing for Casselman
What Canada’s Flood Map Inventory lists for Casselman: who studied flooding and where to see their maps.
No flood study on the national inventory covers Casselman; ask the municipality, which is the authority for its flood maps.
Towns with a flood study on file
Mapping in Ontario reaches 69% of towns, beside 58% across Canada, but not Casselman.
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 Casselman.
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.”
Shaking is Casselman’s costliest hazard: $0.20 a year per $1,000
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
At $0.20 per $1,000, Casselman carries roughly 6.5 times the typical Canadian town’s earthquake risk ($0.030).
Shaking damage a year per $1,000 of building value
Above the middle in Ontario: Casselman’s $0.20 against a median of $0.043, with Alexandria highest at $0.21.
NRCan seismic risk model (2022): mean yearly building loss per $1,000 of value; medians of towns of 2,500 people or more.
12% of Canada’s 2,611 towns expect more shaking damage than Casselman, which places it in the upper third.
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).
Roads, pipes and bridges aren’t in Casselman’s figure, nor landslides or tsunami: it is buildings and shaking.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean).
6.1% of homes tested around Casselman are over the radon guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline.
At 6.1% over the guideline, the area around Casselman is about level with the typical Canadian town’s 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Casselman’s area, at 6.1%, is above the median in Ontario (4%), and 1% of its tests passed 600 Bq/m³.
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 Casselman’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.
One home in Casselman can be high while next door is low; a three-month test settles it.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011). · Data for radon tests covers the The Eastern Ontario Health Unit
Weather and fire alerts for Casselman
Environment and Climate Change Canada issues the weather alerts for Casselman; 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 Casselman, and listen to local authorities for orders.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
Hazards in the places around Casselman
Wildfire band, earthquake risk, radon and flood studies for each place nearby.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Casselman | Low | $0.20 | 6.1% | None listed |
| Limoges 15,122 · 4.3 km | Low | $0.20 | 6.1% | Yes |
| North Stormont 7,946 · 12 km | Low | $0.20 | 6.1% | Yes |
| Embrun 23,655 · 17 km | Low | $0.19 | 6.1% | Yes |
Fire is no heavier anywhere nearby than around Casselman (low), with Limoges next at low.
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Casselman faces
What to do about the hazards Casselman 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
- 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 Casselman floods.
- 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 Casselman sits in.
- Wildfire counts one way. Wildfire is read from the national burned-area record around Casselman’s homes since 1986, a history of fire that may lower Risk but never raises it.
- Earthquakes are modelled. NRCan models what earthquakes would cost buildings each year on average, subdivision by subdivision; Casselman’s figure is its subdivision’s.
Questions about flooding and hazards in Casselman
Is Casselman at risk of wildfire?
Very little by the national record: Casselman’s band is low, with 0% of the land within 25 km burned since 1986, so wildfire doesn’t change its grade.
How big is the earthquake risk in Casselman?
NRCan’s model expects shaking to cost buildings in Casselman $0.20 a year for every $1,000 of their value, on average over many years.
Does Casselman flood?
Nothing is listed for Casselman on the national inventory (0); local maps may still exist with the municipality.
How is Casselman’s Hazard risk Grade worked out?
Hazard risk gives Casselman C, weighing earthquakes and radon and counting wildfire only against it.
Is radon a problem in Casselman?
In Health Canada’s survey, 6.1% of 99 homes tested in Casselman’s area were above 200 Bq/m³, though only a test tells you about one house.
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).