Photo: Nelro2 at en.wikipedia · CC BY 3.0Flood mapping exists for Seaforth: 1 on record, latest by Maitland Valley Conservation Authority
No wildfire is mapped within 25 km of Seaforth’s homes since 1986 (0% of the land, 0.000% a year). Seismic risk runs low: $0.015 of expected damage per $1,000 of buildings a year, the typical town $0.030. Radon is higher than usual: 11% of tested homes in the survey area topped the guideline, against 6.6% for the typical town. Seaforth grades B for hazard risk; wildfire is low here, so it earns no credit.
What stands out about Seaforth’s hazards
For Seaforth, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Seaforth faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Seaforth: B
Risk averages earthquakes and radon; wildfire joins only where it pulls the average down, so a town like Seaforth with little fire nearby would get no credit for it.
Its place: #632 of 866 in Ontario and #1,463 of 2,589 Canadian towns.
How sure: Earthquake losses are a model’s expectation over many years, not a forecast for any one. The burned-area record misses fires under about 10 ha and most grass and farm fires.
Little of the land around Seaforth has burned: 0% within 5 km, 0% within 25 km since 1986
Fires mapped since 1986 around where Seaforth’s residents live, and the fuel next to their homes.
Seaforth burns at 0.000% a year, low against 0.000% for the typical Canadian town.
Little near Seaforth’s homes can carry a forest fire; only 0.4% of the land within 5 km is forest fuel, and 1.1% 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
To three decimals the burn rate around Seaforth 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.
92% of Canada’s 2,610 towns are in the low band and 7.5% above it; Seaforth is among the many where the yearly burn rate rounds to zero.
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.
A flood study covers Seaforth, from Maitland Valley Conservation Authority: 1 on the inventory
Flood studies whose area touches Seaforth, from NRCan’s inventory, each linked to its owner.
The flood study touching Seaforth is Maitland Valley Conservation Authority’s, dated 2024; its own map shows the zones street by street.
| Study | By | Year | Status |
|---|---|---|---|
| North Perth | Maitland Valley Conservation Authority | 2024 | final |
Towns with a flood study on file
69% of towns in Ontario have a flood study, more than Canada’s 58%; Seaforth has one too.
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 Seaforth’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.”
Natural Resources Canada, Canada Flood Map Inventory; links go to each study’s owner.
Low seismic risk in Seaforth: $0.015 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.
0.5 times the typical $0.030: Seaforth’s $0.015 is low for Canada.
Shaking damage a year per $1,000 of building value
Below the middle in Ontario: Seaforth’s $0.015 against a median of $0.043; Alexandria has $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.
Most of Canada’s 2,611 towns (72%) face more earthquake damage than Seaforth.
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).
For Seaforth the model prices shaking damage to buildings, nothing more.
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 Seaforth are over the radon guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline.
Seaforth’s area, at 11%, is above the 6.6% of the typical Canadian town, so testing is worth more here than most places. For radon tests, the only official count covers all of the Huron County Health Unit, Seaforth included.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Around Seaforth, 11% of tests were over 200 Bq/m³ and 0.9% over 600, against a median of 4% in Ontario.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
The 10–20% band holds 22% of Canada’s 2,611 towns, Seaforth among them; 4.6% rank above.
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.
Neighbouring homes in Seaforth can differ a lot; only a long-term test tells you about yours.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Where to get warnings in Seaforth
Environment and Climate Change Canada issues the weather alerts for Seaforth; 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 Seaforth, 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)
How Seaforth’s neighbours compare on hazards
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Seaforth | Low | $0.015 | 11% | Yes |
| Mitchell 10,080 · 19 km | Low | $0.017 | 12% | None listed |
Nowhere around Seaforth burns more: Mitchell, 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 Seaforth faces
What to do about the hazards Seaforth 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
- Radon is a survey. Health Canada’s survey tested some 14,000 homes over three months; until postal-area boundaries are loaded, Seaforth takes its 2007 health region’s share.
- Wildfire counts one way. For Seaforth, wildfire means how much nearby land burned in the past forty years, a one-way input that can pull Risk down and nothing more.
- Earthquakes are modelled. Seismic risk is NRCan’s model of yearly building losses from shaking, averaged over many years and given for Seaforth’s census subdivision (a neighbourhood shows its city’s).
- Flood studies aren’t flood zones. The flood inventory points to maps; it is incomplete and not the official source, so ask the municipality about any street in Seaforth.
Questions about flooding and hazards in Seaforth
Is Seaforth at risk of wildfire?
Very little by the national record: Seaforth’s band is low, with 0% of the land within 25 km burned since 1986, so wildfire doesn’t change its grade.
Does Seaforth flood?
The inventory lists a study touching Seaforth; whether a given street floods is on that map, not in the grade.
How is Seaforth’s Hazard risk Grade worked out?
Seaforth grades B for hazard risk, from earthquakes and radon, with wildfire counted only where it lowers the grade.
Is radon a problem in Seaforth?
Around Seaforth, 106 survey homes were tested and 11% came in over 200 Bq/m³, a guide to the area, not to any one home.
How big is the earthquake risk in Seaforth?
About $0.015 a year per $1,000 of building value, NRCan’s long-run expectation for Seaforth.
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).