Photo: OldYorkGuy · CC BY-SA 3.0A flood study covers Annex: 1 on the national inventory, the newest from Toronto Regional Conservation Authority
No wildfire is mapped within 25 km of Annex’s homes since 1986 (0% of the land, 0.000% a year). For earthquakes Annex is middling, $0.043 a year per $1,000 against $0.030 for the typical town. Fewer homes than usual carry radon here, 2.7% over the guideline where the typical town has 6.6%. Hazard risk gives Annex a grade of A−, from earthquakes and radon alone.
What stands out about Annex’s hazards
Four national sources, each read for Annex: earthquakes, radon, past fires and flood studies.
What Annex faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Annex grades A− for hazard risk
Risk averages earthquakes and radon; wildfire joins only where it pulls the average down, so a town like Annex 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: Earthquake losses are a model’s expectation over many years, not a forecast for any one. 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.
Wildfire is rare near Annex: 0% of the land within 25 km burned since 1986, 0% within 5 km
Past fire around Annex’s homes, from the national burned-area record, with the fuel within 5 km.
Annex burns at 0.000% a year, low against 0.000% for the typical Canadian town.
Land that isn’t forest covers nearly all the ground around Annex: forest fuel is 0.1% within 5 km and 0.9% 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
Near-zero burning puts Annex 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.
Measured against 2,610 towns, Annex 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.
Annex is on the flood map inventory: 1 study, by Toronto Regional Conservation Authority
What Canada’s Flood Map Inventory lists for Annex: who studied flooding and where to see their maps.
Toronto Regional Conservation Authority studied flooding in an area that includes Annex (2021); open its map to see which streets lie in a flood zone.
| Study | By | Year | Status |
|---|---|---|---|
| Toronto Floodline Consolidation | Toronto Regional Conservation Authority | 2021 | final |
Towns with a flood study on file
Flood maps are common in Ontario: 69% of towns have one, against 58% nationally, and Annex is among them.
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 Annex.
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.
Ordinary seismic risk in Annex: $0.043 per $1,000 of buildings a year
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
Earthquake losses in Annex, $0.043 per $1,000, are in line with the typical $0.030 (1.4 times).
Shaking damage a year per $1,000 of building value
Neither high nor low in Ontario: Annex’s $0.043 sits by the median of $0.043, while Alexandria reaches $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.
Annex sits mid-range among Canada’s 2,611 towns: 36% expect more shaking damage.
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 Annex’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). · Earthquake risk: one figure for all of the city of Toronto
Radon runs low around Annex: 2.7% of tested homes over the guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline.
Fewer homes than usual test high around Annex: 2.7% against 6.6% for the typical Canadian town. For radon tests, the only official count covers all of the City of Toronto Health Unit, Annex included.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
The median in Ontario is 4% over 200 Bq/m³; around Annex it is 2.7%.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Annex is in the lowest band, with 37% of Canada’s 2,611 towns: under 5% of tests over the guideline, while 63% have 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.
The survey sampled homes around Annex; it can’t tell you your basement’s level.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Weather and fire alerts for Annex
Alerts for Annex 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 Annex to phones; CWFIS shows the day’s fire danger.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How Annex’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 |
|---|---|---|---|---|
| Annex | Low | $0.043 | 2.7% | Yes |
| University 7,595 · 1.1 km | Low | $0.043 | 2.7% | None listed |
| Casa Loma 11,369 · 1.4 km | Low | $0.043 | 2.7% | None listed |
| Bay-Cloverhill 17,591 · 1.4 km | Low | $0.043 | 2.7% | Yes |
| Church-Wellesley 22,415 · 1.6 km | Low | $0.043 | 2.7% | Yes |
| Palmerston-Little Italy 13,171 · 1.9 km | Low | $0.043 | 2.7% | None listed |
| Yonge-St.Clair 13,177 · 2.1 km | Low | $0.043 | 2.7% | None listed |
Nowhere around Annex burns more: University, 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 Annex faces
What to do about the hazards Annex 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
- Wildfire counts one way. The wildfire figure is the share of land within 25 km of Annex’s homes burned each year from 1986 to 2025, past fire rather than a forecast, and it can only lower Risk.
- Flood studies aren’t flood zones. NRCan’s inventory says where flood mapping exists, not where water goes; the map’s owner is the authority for Annex.
- Radon is a survey. About 14,000 homes were tested across Canada in 2009–2011, and the share over the guideline for Annex is its health region’s, the survey’s design unit.
- 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 Annex’s.
Questions about flooding and hazards in Annex
Is radon a problem in Annex?
Around Annex, 74 survey homes were tested and 2.7% came in over 200 Bq/m³, a guide to the area, not to any one home.
How is Annex’s Hazard risk Grade worked out?
Annex grades A− for hazard risk, from earthquakes and radon, with wildfire counted only where it lowers the grade.
Is Annex at risk of wildfire?
No meaningful wildfire history near Annex: 0% of nearby land since 1986, band low.
Does Annex flood?
There is flood mapping for Annex on the national inventory, each study linked to its owner’s map, none of them graded.
How big is the earthquake risk in Annex?
In NRCan’s seismic model, Annex’s buildings lose $0.043 per $1,000 of value in an average year.
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).