Photo: P199 · CC BY-SA 3.0Wiarton is on Canada’s flood inventory: 2 listed, led by Town of Saugeen Shores
The burned-area map is nearly blank around Wiarton, 0% 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). More homes than usual carry radon here, 11% over the guideline where the typical town has 6.6%. Wiarton grades B for hazard risk; wildfire is low here, so it earns no credit.
What stands out about Wiarton’s hazards
Four national sources, each read for Wiarton: earthquakes, radon, past fires and flood studies.
What Wiarton faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Wiarton grades B for hazard risk
Two inputs always count for Wiarton, earthquakes and radon; the third, wildfire, counts only against a town.
Its place: #619 of 866 in Ontario and #1,421 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 Wiarton: 0% within 5 km, 0% within 25 km
Past fire around Wiarton’s homes, from the national burned-area record, with the fuel within 5 km.
Low by Canadian standards: 0.000% of the land a year around Wiarton, 0.000% for the typical Canadian town.
The ring nearest Wiarton is the most wooded: 27% forest fuel within 5 km against 15% 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 Ontario · highest of 871
Of the 871 towns in Ontario, 638 have a burn rate that rounds to zero, Wiarton among them; Sioux Lookout leads at 0.16% a year.
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 holds 92% of Canada’s 2,610 towns, and Wiarton sits at its very bottom; only 7.5% are above it.
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.
2 flood studies cover Wiarton, the newest from Town of Saugeen Shores
What Canada’s Flood Map Inventory lists for Wiarton: who studied flooding and where to see their maps.
2 studies on the inventory touch Wiarton, the newest Town of Saugeen Shores’s from 2025, and their areas can be large, so they say maps exist, not that the town floods.
| Study | By | Year | Status |
|---|---|---|---|
| Saugeen Shores - Southampton, ON | Town of Saugeen Shores | 2025 | under review |
| Southampton Flood Hazard Mapping | Saugeen Valley Conservation Authority | 2024 | final |
Towns with a flood study on file
Wiarton is one of the 69% of towns in Ontario with a flood study on file; across Canada it is 58%.
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 Wiarton.
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.
Low seismic risk in Wiarton: $0.013 per $1,000 of buildings a year
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
0.4 times the typical $0.030: Wiarton’s $0.013 is low for Canada.
Shaking damage a year per $1,000 of building value
The typical town in Ontario expects $0.043 a year in shaking damage; Wiarton expects less, $0.013, and Alexandria the most, $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.
Toward the quiet end of Canada’s range: 75% of its 2,611 towns sit above Wiarton.
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 Wiarton’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).
11% of homes tested around Wiarton are over the radon guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline. · Measured across the Grey Bruce Health Unit: radon tests
A higher share than most: 11% of tested homes around Wiarton, the typical Canadian town 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Wiarton’s area, at 11%, 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.
4.6% of Canada’s 2,611 towns have a higher share of homes over 200 Bq/m³ than Wiarton, in the 10–20% band with 22%.
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.
The share describes the area, not a house: in Wiarton as anywhere, test to be sure.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Weather and fire alerts for Wiarton
Alerts for Wiarton 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 Wiarton 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 Wiarton’s neighbours compare on hazards
Wildfire band, earthquake risk, radon and flood studies for each place nearby.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Wiarton | Low | $0.013 | 11% | Yes |
| Georgian Bluffs 12,061 · 16 km | Low | $0.012 | 11% | None listed |
The neighbour with the most fire is Georgian Bluffs (low), still no more than Wiarton (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Wiarton faces
What to do about the hazards Wiarton 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?
- Check the address on the flood map.
- Are flood and wildfire insured?
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 Wiarton floods.
- Wildfire counts one way. The wildfire figure is the share of land within 25 km of Wiarton’s homes burned each year from 1986 to 2025, past fire rather than a forecast, and it can only lower Risk.
- 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 Wiarton sits in.
- 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 Wiarton’s.
Questions about flooding and hazards in Wiarton
How is Wiarton’s Hazard risk Grade worked out?
Wiarton’s Hazard risk grade is B, built on earthquakes and radon with a one-sided wildfire input.
Is radon a problem in Wiarton?
Around Wiarton, 98 survey homes were tested and 11% came in over 200 Bq/m³, a guide to the area, not to any one home.
Is Wiarton at risk of wildfire?
Very little by the national record: Wiarton’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 Wiarton?
In NRCan’s seismic model, Wiarton’s buildings lose $0.013 per $1,000 of value in an average year.
Does Wiarton flood?
Wiarton’s area has been studied for flooding, and the owner’s map shows which streets lie in a zone; the grade leaves flood out.
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).