Photo: Earth Science and Remote Sensing Unit , Lyndon B. Johnson Space Center · Public domainRadon is Alonsa’s main hazard: 43% of tested homes in its area top Health Canada’s guideline
Fire seldom reaches Alonsa: since 1986, 0.6% of the land within 25 km has burned (0.02% a year). Shaking is less of a worry than in most places, at $0.005 a year per $1,000 of building value ($0.030 typical). Alonsa grades B− for hazard risk, with wildfire counted against it.
What stands out about Alonsa’s hazards
Four national sources, each read for Alonsa: earthquakes, radon, past fires and flood studies.
What Alonsa faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Alonsa: B−
Seismic risk and radon set Alonsa’s grade, wildfire can drag it down, and flood mapping stays out of it.
How sure: Earthquake losses are a model’s expectation over many years, not a forecast for any one. Small fires and grass fires are largely missing from the national burned-area record.
Little of the land around Alonsa has burned: 0% within 5 km, 0.6% within 25 km since 1986
Fires mapped since 1986 around where Alonsa’s residents live, and the fuel next to their homes.
In a typical year 0.02% of the land near Alonsa burns; the typical Canadian town sees 0.000%, and both are low.
The closest burn since 1986 lies 5.6 km from Alonsa’s homes, none within 5 km.
Forest fuel is scarce around Alonsa: 0.1% of the land within 5 km, 0.2% 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 Manitoba · highest of 190
Flin Flon (Part) burns fastest in Manitoba at 1.68% a year; Alonsa, at 0.02%, ranks 25th of 190.
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.
Some fire is mapped around Alonsa, but not enough to leave the low band, where 92% of Canada’s 2,610 towns are; 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.
No flood study is listed for Alonsa
Flood studies whose area touches Alonsa, from NRCan’s inventory, each linked to its owner.
No flood study on the national inventory covers Alonsa; ask the municipality, which is the authority for its flood maps.
Towns with a flood study on file
Only 18% of towns in Manitoba have a flood study, short of Canada’s 58%, and Alonsa is not among them.
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 Alonsa’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.”
Earthquakes cost buildings in Alonsa just $0.005 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.
Shaking costs the typical town $0.030 a year; in Alonsa it is only $0.005, 0.2 times as much.
Shaking damage a year per $1,000 of building value
Neither high nor low in Manitoba: Alonsa’s $0.005 sits by the median of $0.006, while Virden reaches $0.007.
NRCan seismic risk model (2022): mean yearly building loss per $1,000 of value; medians of towns of 2,500 people or more.
At the bottom of Canada’s range, Alonsa has 96% of the 2,611 towns above it.
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 loss is to Alonsa’s buildings alone, from ground shaking; infrastructure and secondary hazards are left out.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean).
Radon runs high around Alonsa: 43% of tested homes over the guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline. · Measured across the Parkland health region: radon tests
Radon runs above the typical Canadian town (6.6%) in Alonsa’s area, at 43%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Radon runs higher around Alonsa than in most towns in Manitoba: 43% over the guideline (12% is typical), 12% over 600.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
At least three tests in ten top the guideline around Alonsa, a level reached by 1.5% of Canada’s towns.
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.
A survey sample isn’t a map: any home in Alonsa can be high, and a three-month test is the only way to know.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Weather and fire alerts for Alonsa
Environment and Climate Change Canada issues the weather alerts for Alonsa; 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. |
Smoke and fire warnings for Alonsa come through Environment Canada and Alert Ready; the fire map is CWFIS’s.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
Hazards in the places around Alonsa
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Alonsa | Low | $0.005 | 43% | None listed |
| Ebb and Flow 52 1,751 · 18 km | Low | $0.005 | 43% | None listed |
Ebb and Flow 52 burns a little more than Alonsa, in the same low band (low here).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Alonsa faces
Practical steps for Alonsa’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
- Radon is a survey. About 14,000 homes were tested across Canada in 2009–2011, and the share over the guideline for Alonsa is its health region’s, the survey’s design unit.
- Wildfire counts one way. Wildfire is read from the national burned-area record around Alonsa’s homes since 1986, a history of fire that may lower Risk but never raises it.
- Earthquakes are modelled. NRCan models what earthquakes would cost buildings each year on average, subdivision by subdivision; Alonsa’s figure is its subdivision’s.
- 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 Alonsa.
Questions about flooding and hazards in Alonsa
Does Alonsa flood?
The inventory has 0 studies for Alonsa, and an empty list isn’t a clean bill: the municipality holds any flood maps.
How big is the earthquake risk in Alonsa?
Expected earthquake damage in Alonsa comes to $0.005 a year for each $1,000 that buildings are worth.
Is Alonsa at risk of wildfire?
Some, but Alonsa’s low band (0.6% of nearby land burned since 1986, latest 2021) is short of the level that counts.
Is radon a problem in Alonsa?
The area’s survey found 43% of 122 tested homes above Health Canada’s guideline, so a three-month test is worth doing in Alonsa.
How is Alonsa’s Hazard risk Grade worked out?
Alonsa’s Hazard risk grade is B−, built on earthquakes and radon with a one-sided wildfire input.
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).