Photo: Jfvoll · CC BY-SA 4.0Hazards in Mildmay: wildfire low, radon over the guideline in 11% of tested homes
The burned-area map is nearly blank around Mildmay, 0% within 25 km since 1986, 0.000% a year. Seismic risk runs low: $0.012 of expected damage per $1,000 of buildings a year, the typical town $0.030. Hazard risk gives Mildmay a grade of B+, from earthquakes and radon alone.
What stands out about Mildmay’s hazards
Four national sources, each read for Mildmay: earthquakes, radon, past fires and flood studies.
What Mildmay faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Mildmay: B+
Earthquake risk and radon make Mildmay’s grade; wildfire can only lower it, never raise it, and flood studies are listed but not scored.
Its place: #605 of 866 in Ontario and #1,387 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.
Wildfire is rare near Mildmay: 0% of the land within 25 km burned since 1986, 0% within 5 km
Past fire around Mildmay’s homes, from the national burned-area record, with the fuel within 5 km.
Low: the land around Mildmay burns at 0.000% a year, where the typical Canadian town sees 0.000%.
Forest fuel rises from 2.9% within 5 km of Mildmay to 5.2% within 25 km: the fuel lies away from 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
Near-zero burning puts Mildmay with 638 of the 871 towns in Ontario, far below Sioux Lookout at 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.
Mildmay shares the low band with 92% of Canada’s 2,610 towns, its burn rate rounding to nothing; 7.5% 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 Mildmay
What Canada’s Flood Map Inventory lists for Mildmay: who studied flooding and where to see their maps.
NRCan’s inventory is silent on Mildmay, so any flood map would be the municipality’s own.
Towns with a flood study on file
Flood maps are common in Ontario, 69% of towns against 58% nationally, but none in the inventory touches Mildmay.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
Flood is shown here, never graded: a study says where a map exists, not how many of Mildmay’s homes stand in a flood zone.
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.”
Little shaking expected in Mildmay: $0.012 a year per $1,000
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
At $0.012 per $1,000, Mildmay carries 0.4 times the typical Canadian town’s earthquake risk ($0.030): low.
Shaking damage a year per $1,000 of building value
The typical town in Ontario expects $0.043 a year in shaking damage; Mildmay expects less, $0.012, 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: 84% of its 2,611 towns sit above Mildmay.
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 model counts damage to Mildmay’s buildings and their occupants from shaking only: not liquefaction, landslides, tsunami or fires after a quake.
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 Mildmay are over the radon guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline.
Radon runs above the typical Canadian town (6.6%) in Mildmay’s area, at 11%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
More homes top the guideline around Mildmay (11%) than in the typical town in Ontario (4%); 1% went over 600.
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 Mildmay, 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.
Basements, soil and how a house is sealed decide its radon, so in Mildmay only a test can say.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011). · Not measured by town: radon tests (the Grey Bruce Health Unit)
Weather and fire alerts for Mildmay
Environment and Climate Change Canada issues the weather alerts for Mildmay; 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. |
For fires near Mildmay, the national fire information system maps danger and active fires daily; local authorities give any evacuation order.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
Hazards in the places around Mildmay
Wildfire band, earthquake risk, radon and flood studies for each place nearby.
Nowhere around Mildmay burns more: Walkerton, 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 Mildmay faces
Practical steps for Mildmay’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?
- Ask the municipality for flood maps.
- 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 Mildmay 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 Mildmay sits in.
- Wildfire counts one way. Wildfire is read from the national burned-area record around Mildmay’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; Mildmay’s figure is its subdivision’s.
Questions about flooding and hazards in Mildmay
Does Mildmay flood?
No study on Canada’s Flood Map Inventory covers Mildmay (0), which doesn’t mean it has never been mapped, so ask the municipality.
Is Mildmay at risk of wildfire?
Very little by the national record: Mildmay’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 Mildmay?
In NRCan’s seismic model, Mildmay’s buildings lose $0.012 per $1,000 of value in an average year.
Is radon a problem in Mildmay?
11% of the 98 homes Health Canada tested around Mildmay topped the guideline; your own house needs its own test.
How is Mildmay’s Hazard risk Grade worked out?
Hazard risk gives Mildmay B+, 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).