Photo: Blake Handley from Victoria, Canada · CC BY 2.0Earthquake risk in North Cowichan runs 25 times the typical Canadian town’s: $0.76 per $1,000 a year
Little of the land around North Cowichan has burned: 0.1% within 25 km since 1986, or 0.003% a year. Fewer homes than usual carry radon here, 0.9% over the guideline where the typical town has 6.6%. North Cowichan grades B− for hazard risk, with wildfire counted against it.
What stands out about North Cowichan’s hazards
For North Cowichan, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What North Cowichan faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in North Cowichan: B−
Two inputs always count for North Cowichan, earthquakes and radon; the third, wildfire, counts only against a town.
Its place: #135 of 254 in British Columbia and #1,666 of 2,589 Canadian towns.
How sure: Earthquake losses are a model’s expectation over many years, not a forecast for any one. The burned-area record misses fires under about 10 ha and most grass and farm fires.
Few fires near North Cowichan: 0.1% within 5 km, 0.1% within 25 km
Past fire around North Cowichan’s homes, from the national burned-area record, with the fuel within 5 km.
Fire claims 0.003% of the land around North Cowichan each year, a low band, with the typical Canadian town at 0.000%.
Within 5 km of North Cowichan, 57% of the land is forest fuel; widen the ring to 25 km and it is 75%.
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
Some fire is mapped around North Cowichan (0.003% a year), but it ranks only 191st of 255 towns in British Columbia; Oliver has 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.
North Cowichan is in the low band with 92% of Canada’s 2,610 towns; 7.5% sit in moderate or 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.
Flooding around North Cowichan is mapped in 5 studies, the newest by Cowichan Valley Regional District
What Canada’s Flood Map Inventory lists for North Cowichan: who studied flooding and where to see their maps.
Cowichan Valley Regional District and others have studied flooding in areas that include North Cowichan: 5 studies, the latest from 2022.
| Study | By | Year | Status |
|---|---|---|---|
| Chemainus River Flood Mapping Program Part 1 Flood Mapping | Cowichan Valley Regional District | 2022 | final |
| Capital Regional Coastal Flood Inundation Mapping Project | Capital Regional District | 2021 | final |
| Lower Cowichan/Koksilah River Integrated Flood Management Plan | Cowichan Valley Regional District | 2009 | final |
| Cowichan and Koksilah Rivers at Duncan Floodplain Mapping | Ministry of Environment and Climate Change Strategy | 1997 | final |
| Chemainus River Floodplain Mapping (including Bonsall Creek) | Ministry of Environment and Climate Change Strategy | 1991 | final |
Towns with a flood study on file
North Cowichan is one of the 76% of towns in British Columbia 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.
No single decade dominates: 5 studies for North Cowichan between the 1990s and the 2020s.
Study dates as the NRCan inventory lists them, one count per study touching North Cowichan.
The grade leaves flood out, since a study area says nothing about how many of North Cowichan’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.”
Natural Resources Canada, Canada Flood Map Inventory; links go to each study’s owner.
Shaking is North Cowichan’s costliest hazard: $0.76 a year per $1,000
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
The typical town loses $0.030 a year to shaking; North Cowichan loses $0.76, 25.2 times as much.
Shaking damage a year per $1,000 of building value
Earthquake risk in British Columbia peaks in Duncan ($1.33); North Cowichan, at $0.76, sits above the median of $0.36.
NRCan seismic risk model (2022): mean yearly building loss per $1,000 of value; medians of towns of 2,500 people or more.
Few of Canada’s 2,611 towns face more earthquake damage than North Cowichan: 0.4% of them.
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 North Cowichan 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).
0.9% of homes tested around North Cowichan are over the radon guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline. · Source area for radon tests: the Central Vancouver Island health region
Where the typical Canadian town has 6.6% of homes over the guideline, North Cowichan’s area has fewer, 0.9%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Fewer homes top the guideline around North Cowichan (0.9%) than in the typical town in British Columbia (1.8%).
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
North Cowichan 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.
Radon varies from house to house in North Cowichan, 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 North Cowichan
Environment and Climate Change Canada issues the weather alerts for North Cowichan; 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 North Cowichan come through Environment Canada and Alert Ready; the fire map is CWFIS’s.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
How North Cowichan’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 |
|---|---|---|---|---|
| North Cowichan | Low | $0.76 | 0.9% | Yes |
| Duncan 5,745 · 3.6 km | Low | $1.33 | 0.9% | Yes |
| Cowichan 2,509 · 4.8 km | Low | $0.72 | 0.9% | Yes |
| Electoral Area E, Cowichan Valley 4,482 · 5.1 km | Low | $0.83 | 0.9% | Yes |
| Cowichan Bay 3,713 · 10 km | Low | $1.08 | 0.9% | Yes |
| Saltspring Island 12,429 · 14 km | Low | $0.42 | 1.8% | Yes |
| Cobble Hill 5,074 · 16 km | Low | $0.68 | 0.9% | None listed |
The neighbour with the most fire is Duncan (low), still no more than North Cowichan (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what North Cowichan faces
What to do about the hazards North Cowichan 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.
- Drop, cover and hold on.
- Strap the water heater down.
- Keep 72 hours of supplies.
- Has it had a radon test?
- Check the address on the flood map.
- Are flood and wildfire insured?
- Is earthquake cover included?
What this data can and can’t tell you
- Earthquakes are modelled. Seismic risk is NRCan’s model of yearly building losses from shaking, averaged over many years and given for North Cowichan’s census subdivision (a neighbourhood shows its city’s).
- Radon is a survey. About 14,000 homes were tested across Canada in 2009–2011, and the share over the guideline for North Cowichan is its health region’s, the survey’s design unit.
- Wildfire counts one way. For North Cowichan, wildfire means how much nearby land burned in the past forty years, a one-way input that can pull Risk down and nothing more.
- 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 North Cowichan.
Questions about flooding and hazards in North Cowichan
Is North Cowichan at risk of wildfire?
Fire has reached 0.1% of the land around North Cowichan since 1986 (last in 2024); at low, it neither helps nor hurts the grade.
Does North Cowichan flood?
There is flood mapping for North Cowichan on the national inventory, each study linked to its owner’s map, none of them graded.
Is radon a problem in North Cowichan?
Around North Cowichan, 109 survey homes were tested and 0.9% came in over 200 Bq/m³, a guide to the area, not to any one home.
How big is the earthquake risk in North Cowichan?
In NRCan’s seismic model, North Cowichan’s buildings lose $0.76 per $1,000 of value in an average year.
How is North Cowichan’s Hazard risk Grade worked out?
Hazard risk gives North Cowichan B−, weighing earthquakes and radon and counting wildfire only against it.
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).