Photo: Quinn Desilets · CC BY-SA 4.0Around Nelson, 29% of tested homes have radon above the guideline
The burn rate around Nelson is 0.21% a year (8.3% of the land within 25 km since 1986), a moderate band. Shaking is less of a worry than in most places, at $0.007 a year per $1,000 of building value ($0.030 typical). Nelson grades C+ for hazard risk, with wildfire counted against it.
What stands out about Nelson’s hazards
Four national sources, each read for Nelson: earthquakes, radon, past fires and flood studies.
What Nelson faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Nelson grades C+ for hazard risk
Two inputs always count for Nelson, earthquakes and radon; the third, wildfire, counts only against a town.
Its place: #183 of 254 in British Columbia and #1,796 of 2,589 Canadian towns.
How sure: The seismic figure is a long-run average from NRCan’s model, not a prediction. Small fires and grass fires are largely missing from the national burned-area record.
A moderate wildfire record for Nelson: 8.3% within 25 km burned, 0.2% within 5 km
Past fire around Nelson’s homes, from the national burned-area record, with the fuel within 5 km.
The yearly burn rate around Nelson is 0.21%, above 0.000% for the typical Canadian town but under the high band.
Forest fuel is denser close to Nelson (82% within 5 km) than further out (71% 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 British Columbia · highest of 255
In the top quarter in British Columbia: Nelson ranks 33rd of 255 at 0.21% a year, with Oliver first at 0.98%.
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.
Only 5.4% of Canada’s 2,610 towns share the moderate band with Nelson, and 2.1% sit above it.
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.
The flood map inventory lists nothing for Nelson
What Canada’s Flood Map Inventory lists for Nelson: who studied flooding and where to see their maps.
Canada’s Flood Map Inventory lists no study whose area touches Nelson, which doesn’t mean it has never been mapped.
Towns with a flood study on file
Flood maps are common in British Columbia, 76% of towns against 58% nationally, but none in the inventory touches Nelson.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
Listed, not scored: a flood study proves a map exists, not that Nelson floods.
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.”
Low seismic risk in Nelson: $0.007 per $1,000 of buildings a year
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
Nelson’s $0.007 is a fraction of the typical town’s $0.030 (0.2 times as much): quiet ground by Canadian standards.
Shaking damage a year per $1,000 of building value
At $0.007, Nelson is below the typical town in British Columbia ($0.36); Duncan is highest at $1.33.
NRCan seismic risk model (2022): mean yearly building loss per $1,000 of value; medians of towns of 2,500 people or more.
Toward the quiet end of Canada’s range: 88% of its 2,611 towns sit above Nelson.
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).
Roads, pipes and bridges aren’t in Nelson’s figure, nor landslides or tsunami: it is buildings and shaking.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean).
Test for radon in Nelson: 29% of area homes were over the guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline. · The radon tests numbers here cover the Kootenay/Boundary health region
Nelson’s area, at 29%, is above the 6.6% of the typical Canadian town, so testing is worth more here than most places.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
More homes top the guideline around Nelson (29%) than in the typical town in British Columbia (1.8%); 7.3% went over 600.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Nelson is in the 20–30% band, which holds only 3.1% of Canada’s 2,611 towns; 1.5% are higher.
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 Nelson 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 Nelson
Alerts for Nelson 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 Nelson to phones; CWFIS shows the day’s fire danger.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
Hazards in the places around Nelson
Wildfire band, earthquake risk, radon and flood studies for each place nearby.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Nelson | Moderate | $0.007 | 29% | None listed |
| Electoral Area E, Central Kootenay 4,309 · 3.2 km | Moderate | $0.007 | 29% | None listed |
| Electoral Area F, Central Kootenay 4,209 · 4.8 km | Moderate | $0.007 | 29% | None listed |
None of the places around has more fire nearby than Nelson (moderate); Electoral Area F, Central Kootenay comes closest (moderate).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Nelson faces
What to do about the hazards Nelson faces, and what to ask before you buy.
- Clear needles and wood nearby.
- Keep a grab-and-go bag ready.
- In smoke, stay in; filter air.
- 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.
- Has it had a radon test?
- Ask the municipality for flood maps.
- How close is the forest edge?
- Are flood and wildfire insured?
What this data can and can’t tell you
- Wildfire counts one way. Wildfire is read from the national burned-area record around Nelson’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 Nelson floods.
- Earthquakes are modelled. NRCan models what earthquakes would cost buildings each year on average, subdivision by subdivision; Nelson’s figure is its subdivision’s.
- 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 Nelson sits in.
Questions about flooding and hazards in Nelson
How is Nelson’s Hazard risk Grade worked out?
Nelson’s Hazard risk grade is C+, built on earthquakes and radon with a one-sided wildfire input.
Does Nelson flood?
Nothing is listed for Nelson on the national inventory (0); local maps may still exist with the municipality.
Is radon a problem in Nelson?
In Health Canada’s survey, 29% of 109 homes tested in Nelson’s area were above 200 Bq/m³, though only a test tells you about one house.
How big is the earthquake risk in Nelson?
In NRCan’s seismic model, Nelson’s buildings lose $0.007 per $1,000 of value in an average year.
Is Nelson at risk of wildfire?
Less than most of Canada: 8.3% of the land within 25 km of Nelson has burned since 1986, the last in 2025, a moderate band that leaves Risk alone.
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).