Photo: GTD Aquitaine · Public domainA flood study covers Henry Farm: 1 on the national inventory, the newest from Toronto Regional Conservation Authority
The national fire record shows next to nothing around Henry Farm, 0% of the land within 25 km since 1986 (0.001% a year). Seismic risk in Henry Farm sits near the middle: $0.043 of expected damage per $1,000 of buildings a year, the typical town $0.030. Fewer homes than usual carry radon here, 2.7% over the guideline where the typical town has 6.6%. Hazard risk gives Henry Farm a grade of A−; its wildfire band pulls it down.
What stands out about Henry Farm’s hazards
Four national sources, each read for Henry Farm: earthquakes, radon, past fires and flood studies.
What Henry Farm faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Henry Farm grades A− for hazard risk
Risk averages earthquakes and radon; wildfire joins only where it pulls the average down, so a town like Henry Farm with little fire nearby would get no credit for it.
Its place: #285 of 866 in Ontario and #700 of 2,589 Canadian towns.
How sure: The seismic figure is a long-run average from NRCan’s model, not a prediction. Only 74 homes were tested in the survey area, so the radon share is rough. Small fires and grass fires are largely missing from the national burned-area record.
Few fires near Henry Farm: 0% within 5 km, 0% within 25 km
Fires mapped since 1986 around where Henry Farm’s residents live, and the fuel next to their homes.
Fire claims 0.001% of the land around Henry Farm each year, a low band, with the typical Canadian town at 0.000%.
The closest burn since 1986 lies 18 km from Henry Farm’s homes, none within 5 km.
Forest fuel is scarce around Henry Farm: 0.2% of the land within 5 km, 2.6% 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
In the top quarter in Ontario: Henry Farm ranks 83rd of 871 at 0.001% a year, with Sioux Lookout first 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.
Beside 2,610 Canadian towns, Henry Farm reads low, with 92% of them; only 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.
A flood study covers Henry Farm, from Toronto Regional Conservation Authority: 1 on the inventory
Flood studies whose area touches Henry Farm, from NRCan’s inventory, each linked to its owner.
For Henry Farm the inventory points to Toronto Regional Conservation Authority’s 2021 study, whose map is the one to check.
| Study | By | Year | Status |
|---|---|---|---|
| Toronto Floodline Consolidation | Toronto Regional Conservation Authority | 2021 | final |
Towns with a flood study on file
Its flood study puts Henry Farm with 69% of towns in Ontario; Canada’s share is 58%.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
Flood mapping is shown for Henry Farm to be opened and checked, never turned into a grade.
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.
Earthquakes cost buildings in Henry Farm $0.043 per $1,000 a year
NRCan’s seismic risk model: the damage shaking is expected to do to buildings each year, on average over many years.
Henry Farm’s $0.043 is close to the typical town’s $0.030 (1.4 times as much).
Henry Farm shares its earthquake risk numbers with the rest of the city of Toronto.
Shaking damage a year per $1,000 of building value
The median in Ontario is $0.043; Henry Farm, at $0.043, is right beside it, and Alexandria tops the list 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.
Neither high nor low for Canada: 36% of the 2,611 towns expect more damage than Henry Farm.
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 Henry Farm’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).
Radon runs low around Henry Farm: 2.7% of tested homes over the 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 City of Toronto Health Unit
Where the typical Canadian town has 6.6% of homes over the guideline, Henry Farm’s area has fewer, 2.7%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Radon runs lower around Henry Farm than in most towns in Ontario: 2.7% against 4%.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Radon rarely tops the guideline around Henry Farm, as for 37% of Canada’s 2,611 towns; 63% see more.
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 Henry Farm 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).
Weather and fire alerts for Henry Farm
Alerts for Henry Farm 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 Henry Farm to phones; CWFIS shows the day’s fire danger.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How Henry Farm’s neighbours compare on hazards
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Henry Farm | Low | $0.043 | 2.7% | Yes |
| Don Valley Village 26,972 · 1.3 km | Low | $0.043 | 2.7% | Yes |
| Fenside-Parkwoods 20,615 · 1.7 km | Low | $0.043 | 2.7% | Yes |
| Pleasant View 15,248 · 1.8 km | Low | $0.043 | 2.7% | None listed |
| L'Amoreaux West 21,575 · 2.6 km | Low | $0.043 | 2.7% | Yes |
| Parkwoods-O'Connor Hills 13,943 · 2.9 km | Low | $0.043 | 2.7% | Yes |
| Bayview Village 22,617 · 3.1 km | Low | $0.043 | 2.7% | Yes |
Fire is no heavier anywhere nearby than around Henry Farm (low), with Don Valley Village next at low.
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Henry Farm faces
What to do about the hazards Henry Farm 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. The radon share comes from about 14,000 long-term home tests in 2009–2011, pooled for now by the 2007 health region Henry Farm sits in.
- Earthquakes are modelled. NRCan models what earthquakes would cost buildings each year on average, subdivision by subdivision; Henry Farm’s figure is its subdivision’s.
- Wildfire counts one way. Wildfire is read from the national burned-area record around Henry Farm’s homes since 1986, a history of fire that may lower Risk but never raises it.
- 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 Henry Farm floods.
Questions about flooding and hazards in Henry Farm
Does Henry Farm flood?
Henry Farm’s area has been studied for flooding, and the owner’s map shows which streets lie in a zone; the grade leaves flood out.
Is Henry Farm at risk of wildfire?
Fire has reached 0% of the land around Henry Farm since 1986 (last in 2001); at low, it neither helps nor hurts the grade.
How big is the earthquake risk in Henry Farm?
Expected earthquake damage in Henry Farm comes to $0.043 a year for each $1,000 that buildings are worth.
How is Henry Farm’s Hazard risk Grade worked out?
Henry Farm’s Hazard risk grade is A−, built on earthquakes and radon with a one-sided wildfire input.
Is radon a problem in Henry Farm?
Around Henry Farm, 74 survey homes were tested and 2.7% came in over 200 Bq/m³, a guide to the area, not to any one home.
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).