Photo: Silver Dovelet · CC BY-SA 3.0Box Grove faces fewer hazards than 88% of Canadian towns
Since 1986 almost nothing has burned near Box Grove: 0% of the land within 25 km, or 0.001% a year. NRCan expects $0.034 of shaking damage a year per $1,000 of buildings in Box Grove, near the typical $0.030. Fewer homes than usual carry radon here, 0% over the guideline where the typical town has 6.6%. Box Grove grades A for hazard risk, with wildfire counted against it.
What stands out about Box Grove’s hazards
For Box Grove, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Box Grove faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Box Grove: A
For Box Grove, Risk will be the average of earthquakes and radon, with wildfire added only if it makes the average worse.
Its place: #165 of 866 in Ontario and #484 of 2,589 Canadian towns.
How sure: The seismic figure is a long-run average from NRCan’s model, not a prediction. The burned-area record misses fires under about 10 ha and most grass and farm fires.
Wildfire is rare near Box Grove: 0% of the land within 25 km burned since 1986, 0% within 5 km
Fires mapped since 1986 around where Box Grove’s residents live, and the fuel next to their homes.
Low: the land around Box Grove burns at 0.001% a year, where the typical Canadian town sees 0.000%.
The 5 km ring around Box Grove’s homes is clear of burns since 1986, the nearest 5.4 km out.
Forest fuel rises from 3.6% within 5 km of Box Grove to 7.2% 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
In the top quarter in Ontario: Box Grove 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.
7.5% of Canada’s 2,610 towns burn fast enough to rank moderate or above; Box Grove stays low, with 92%.
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.
Box Grove is on the flood map inventory: 2 studies, latest by Toronto Regional Conservation Authority
Flood studies whose area touches Box Grove, from NRCan’s inventory, each linked to its owner.
The newest of 2 studies covering Box Grove is Toronto Regional Conservation Authority’s, from 2021; open its map to see the zones.
| Study | By | Year | Status |
|---|---|---|---|
| Toronto Floodline Consolidation | Toronto Regional Conservation Authority | 2021 | final |
| Unionville Special Policy Area | Toronto and Region Conservation Authority | 2019 | final |
Towns with a flood study on file
Box Grove 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 mapping around Box Grove has come in steps: 2 studies from the 2010s to the 2020s.
Study dates as the NRCan inventory lists them, one count per study touching Box Grove.
Flood studies don’t enter the grade; they are listed so you can open the official map for Box Grove.
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 Box Grove: $0.034 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.
With $0.034 of shaking damage a year per $1,000, Box Grove is about even with the typical $0.030 (1.1 times).
Shaking damage a year per $1,000 of building value
Box Grove’s $0.034 sits under the median in Ontario, $0.043, and well under Alexandria’s $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.
Box Grove’s earthquake risk lands near the centre of Canada’s range; 46% of the 2,611 towns are higher.
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).
What a quake does after the shaking, fire, landslides, tsunami, falls outside NRCan’s figure for Box Grove.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean). · Earthquake risk: the city of Markham
Little radon around Box Grove: 0% of area homes over the guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline.
Radon runs below the typical Canadian town (6.6%) in Box Grove’s area, at 0%. Box Grove doesn’t get its own radon tests figures; the ones here come from the York Regional Health Unit.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Box Grove’s area, at 0%, is below the median in Ontario (4%).
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Few tests over the guideline: Box Grove shares the bottom band with 37% of Canada’s 2,611 towns, below the other 63%.
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 Box Grove 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 Box Grove
Alerts for Box Grove 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 Box Grove to phones; CWFIS shows the day’s fire danger.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How Box Grove’s neighbours compare on hazards
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Box Grove | Low | $0.034 | 0% | Yes |
| Vinegar Hill 19,543 · 1.8 km | Low | $0.034 | 0% | Yes |
| Markham Village 10,319 · 3.2 km | Low | $0.034 | 0% | Yes |
| Cornell 22,014 · 4.0 km | Low | $0.034 | 0% | Yes |
| Mount Joy 8,345 · 4.1 km | Low | $0.034 | 0% | Yes |
| Hagerman's Corners 43,555 · 4.3 km | Low | $0.034 | 0% | Yes |
| Morningside Heights 24,972 · 4.6 km | Low | $0.043 | 2.7% | Yes |
Vinegar Hill (low) has the heaviest fire record of Box Grove’s neighbours, and Box Grove (low) matches or beats it.
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Box Grove faces
Practical steps for Box Grove’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?
- 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 Box Grove sits in.
- 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 Box Grove floods.
- Wildfire counts one way. Burned land within 25 km of where people live, averaged over 1986–2025 and checked for fuel near homes, is the measure; it looks back, not ahead, and only ever counts against Box Grove.
- Earthquakes are modelled. The earthquake figure is an expected loss, not a forecast, worked out by NRCan for each census subdivision, Box Grove’s included.
Questions about flooding and hazards in Box Grove
Is radon a problem in Box Grove?
The area’s survey found 0% of 95 tested homes above Health Canada’s guideline, so a three-month test is worth doing in Box Grove.
How big is the earthquake risk in Box Grove?
About $0.034 a year per $1,000 of building value, NRCan’s long-run expectation for Box Grove.
Is Box Grove at risk of wildfire?
Some, but Box Grove’s low band (0% of nearby land burned since 1986, latest 2001) is short of the level that counts.
How is Box Grove’s Hazard risk Grade worked out?
Hazard risk gives Box Grove A, weighing earthquakes and radon and counting wildfire only against it.
Does Box Grove flood?
Box Grove’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).