Photo: U.S. Coast Guard · Public domainEarthquakes are Comox’s biggest hazard: $0.49 of damage a year per $1,000 of buildings, 16 times the norm
Since 1986 almost nothing has burned near Comox: 0% of the land within 25 km, or 0.000% a year. Radon is lower than usual: 0.9% of tested homes in the survey area topped the guideline, against 6.6% for the typical town. Comox grades B− for hazard risk; wildfire is low here, so it earns no credit.
What stands out about Comox’s hazards
Four national sources, each read for Comox: earthquakes, radon, past fires and flood studies.
What Comox faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Comox grades B− for hazard risk
The grade weighs Comox’s seismic risk and radon equally, and wildfire is one-sided: a high band counts against a town, a low one earns nothing.
Its place: #121 of 254 in British Columbia and #1,635 of 2,589 Canadian towns.
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.
Few fires near Comox: 0% within 5 km, 0% within 25 km
Past fire around Comox’s homes, from the national burned-area record, with the fuel within 5 km.
The yearly burn rate around Comox is 0.000%, low beside 0.000% for the typical Canadian town.
Comox’s homes have had no fire within 5 km since 1986; the closest was 13 km away.
Forest fuel covers 21% of the land close to Comox and 66% across 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
Of the 255 towns in British Columbia, 7 have a burn rate that rounds to zero, Comox among them; Oliver leads at 0.98% 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.
Comox 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.
Comox is on the flood map inventory: 1 study, by Ministry of Environment and Climate Change Strategy
What Canada’s Flood Map Inventory lists for Comox: who studied flooding and where to see their maps.
For Comox the inventory points to Ministry of Environment and Climate Change Strategy’s 1991 study, whose map is the one to check.
| Study | By | Year | Status |
|---|---|---|---|
| Courtenay, Puntledge and Tsolum River Floodplain Mapping | Ministry of Environment and Climate Change Strategy | 1991 | final |
Towns with a flood study on file
Mapping in British Columbia reaches 76% of towns, Comox included, beside 58% across Canada.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
Flood mapping is shown for Comox to be opened and checked, never turned into a grade.
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 Comox’s costliest hazard: $0.49 a year per $1,000
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
At $0.49 per $1,000, Comox carries roughly 16.3 times the typical Canadian town’s earthquake risk ($0.030).
Shaking damage a year per $1,000 of building value
Comox’s $0.49 tops the median in British Columbia, $0.36, though Duncan reaches $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.
Only 1.4% of Canada’s 2,611 towns expect more shaking damage than Comox.
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 Comox’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).
0.9% of homes tested around Comox are over the radon guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline. · Radon tests for the North Vancouver Island health region
A lower share than most: 0.9% of tested homes around Comox, the typical Canadian town 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Comox’s area, at 0.9%, is below the median in British Columbia (1.8%).
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Radon rarely tops the guideline around Comox, as for 37% of Canada’s 2,611 towns; 63% see 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.
The share describes the area, not a house: in Comox as anywhere, test to be sure.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Weather and fire alerts for Comox
Alerts for Comox 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 Comox 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 Comox
Wildfire band, earthquake risk, radon and flood studies for each place nearby.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Comox | Low | $0.49 | 0.9% | Yes |
| Courtenay 32,869 · 4.4 km | Low | $0.39 | 0.9% | Yes |
| Electoral Area B (Lazo North), Comox Valley 7,830 · 4.6 km | Low | $0.41 | 0.9% | Yes |
| Cumberland 4,974 · 10 km | Low | $0.41 | 0.9% | None listed |
| Electoral Area A, Comox Valley 8,415 · 13 km | Low | $0.37 | 0.9% | None listed |
| Electoral Area C (Puntledge - Black Creek), Comox Valley 9,803 · 16 km | Low | $0.38 | 0.9% | Yes |
The fire record around Electoral Area A, Comox Valley is a touch heavier than Comox’s, but the band is the same: low (here low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Comox faces
What to do about the hazards Comox 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
- Wildfire counts one way. Wildfire is read from the national burned-area record around Comox’s homes since 1986, a history of fire that may lower Risk but never raises it.
- Radon is a survey. About 14,000 homes were tested across Canada in 2009–2011, and the share over the guideline for Comox is its health region’s, the survey’s design unit.
- Earthquakes are modelled. NRCan models what earthquakes would cost buildings each year on average, subdivision by subdivision; Comox’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 Comox.
Questions about flooding and hazards in Comox
How is Comox’s Hazard risk Grade worked out?
Hazard risk gives Comox B−, weighing earthquakes and radon and counting wildfire only against it.
Does Comox flood?
There is flood mapping for Comox on the national inventory, each study linked to its owner’s map, none of them graded.
How big is the earthquake risk in Comox?
In NRCan’s seismic model, Comox’s buildings lose $0.49 per $1,000 of value in an average year.
Is Comox at risk of wildfire?
Less than most of Canada: 0% of the land within 25 km of Comox has burned since 1986, the last in 2025, a low band that leaves Risk alone.
Is radon a problem in Comox?
In Health Canada’s survey, 0.9% of 106 homes tested in Comox’s area were above 200 Bq/m³, though only a test tells you about one house.
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).