Photo: Jacques Dupont · CC BY-SA 3.0Bolton-Est’s hazards at a glance: a low wildfire record and 7.3% of area homes over the radon guideline
Wildfire barely registers for Bolton-Est, at 0% of the land within 25 km since 1986 (0.000% a year). NRCan expects $0.036 of shaking damage a year per $1,000 of buildings in Bolton-Est, near the typical $0.030. Hazard risk gives Bolton-Est a grade of B+, from earthquakes and radon alone.
What stands out about Bolton-Est’s hazards
For Bolton-Est, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Bolton-Est faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Bolton-Est: B+
For Bolton-Est, Risk will be the average of earthquakes and radon, with wildfire added only if it makes the average worse.
How sure: Earthquake losses are a model’s expectation over many years, not a forecast for any one. Only 55 homes were tested in the survey area, so the radon share is rough. The burned-area record misses fires under about 10 ha and most grass and farm fires.
Little of the land around Bolton-Est has burned: 0% within 5 km, 0% within 25 km since 1986
Past fire around Bolton-Est’s homes, from the national burned-area record, with the fuel within 5 km.
Around Bolton-Est fire takes 0.000% of the land in a typical year, the typical Canadian town 0.000%, which is low.
Bolton-Est’s homes have had no fire within 5 km since 1986; the closest was 12 km away.
Forest thickens with distance from Bolton-Est: 12% of the land within 5 km, 27% 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 Quebec · highest of 514
Of the 514 towns in Quebec, 145 have a burn rate that rounds to zero, Bolton-Est among them; Mistissini leads at 0.31% a year.
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.
Bolton-Est 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.
No flood study is listed for Bolton-Est
What Canada’s Flood Map Inventory lists for Bolton-Est: who studied flooding and where to see their maps.
No flood study on the national inventory covers Bolton-Est; ask the municipality, which is the authority for its flood maps.
Towns with a flood study on file
Only 45% of towns in Quebec have a flood study, short of Canada’s 58%, and Bolton-Est is not among them.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
The grade leaves flood out, since a study area says nothing about how many of Bolton-Est’s homes are at risk.
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.”
Ordinary seismic risk in Bolton-Est: $0.036 per $1,000 of buildings a year
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
With $0.036 of shaking damage a year per $1,000, Bolton-Est is about even with the typical $0.030 (1.2 times).
Shaking damage a year per $1,000 of building value
The typical town in Quebec expects $0.14 a year in shaking damage; Bolton-Est expects less, $0.036, and La Pocatière the most, $0.48.
NRCan seismic risk model (2022): mean yearly building loss per $1,000 of value; medians of towns of 2,500 people or more.
Bolton-Est sits mid-range among Canada’s 2,611 towns: 46% 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).
For Bolton-Est 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).
Radon about average around Bolton-Est: 7.3% over the guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline.
7.3% of tested homes around Bolton-Est were over the guideline, much like the typical Canadian town at 6.6%. Bolton-Est doesn’t get its own radon tests figures; the ones here come from the Estrie health region.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Radon around Bolton-Est is ordinary for towns in Quebec: 7.3%, beside a median of 8.2%.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Radon tops the guideline in a modest share of homes around Bolton-Est, a band holding 37% of Canada’s 2,611 towns; 26% 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.
Radon varies from house to house in Bolton-Est, so the survey is a reason to test, not a result for yours.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Where to get warnings in Bolton-Est
Environment and Climate Change Canada issues the weather alerts for Bolton-Est; 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. |
In fire season, check CWFIS for danger and active fires around Bolton-Est, and listen to local authorities for orders.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How Bolton-Est’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 |
|---|---|---|---|---|
| Bolton-Est | Low | $0.036 | 7.3% | None listed |
| Austin 1,959 · 9.1 km | Low | $0.042 | 7.3% | None listed |
| Eastman 2,706 · 13 km | Low | $0.040 | 7.3% | Yes |
| Potton 2,201 · 15 km | Low | $0.038 | 7.3% | None listed |
| Stukely-Sud 1,242 · 16 km | Low | $0.053 | 7.3% | None listed |
| Lac-Brome 6,307 · 16 km | Low | $0.051 | 8.2% | None listed |
| Magog 30,764 · 16 km | Low | $0.047 | 7.3% | None listed |
The neighbour with the most fire is Austin (low), still no more than Bolton-Est (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Bolton-Est faces
Practical steps for Bolton-Est’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
- 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 Bolton-Est.
- 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 Bolton-Est.
- Radon is a survey. Health Canada’s survey tested some 14,000 homes over three months; until postal-area boundaries are loaded, Bolton-Est takes its 2007 health region’s share.
- Earthquakes are modelled. The earthquake figure is an expected loss, not a forecast, worked out by NRCan for each census subdivision, Bolton-Est’s included.
Questions about flooding and hazards in Bolton-Est
Is radon a problem in Bolton-Est?
The area’s survey found 7.3% of 55 tested homes above Health Canada’s guideline, so a three-month test is worth doing in Bolton-Est.
Is Bolton-Est at risk of wildfire?
Some, but Bolton-Est’s low band (0% of nearby land burned since 1986, latest 2016) is short of the level that counts.
How big is the earthquake risk in Bolton-Est?
NRCan’s model expects shaking to cost buildings in Bolton-Est $0.036 a year for every $1,000 of their value, on average over many years.
Does Bolton-Est flood?
The inventory has 0 studies for Bolton-Est, and an empty list isn’t a clean bill: the municipality holds any flood maps.
How is Bolton-Est’s Hazard risk Grade worked out?
Bolton-Est grades B+ for hazard risk, from earthquakes and radon, with wildfire counted only where it lowers the grade.
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).