Photo: Alasdair McLellan · CC BY-SA 3.0Earthquakes are Cobble Hill’s biggest hazard: $0.68 of damage a year per $1,000 of buildings, 23 times the norm
Little of the land around Cobble Hill has burned: 0.1% within 25 km since 1986, or 0.003% 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. Hazard risk gives Cobble Hill a grade of B−; its wildfire band pulls it down.
What stands out about Cobble Hill’s hazards
For Cobble Hill, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Cobble Hill faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Cobble Hill grades B− for hazard risk
The grade weighs Cobble Hill’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: #131 of 254 in British Columbia and #1,661 of 2,589 Canadian towns.
How sure: The seismic figure is a long-run average from NRCan’s model, not a prediction. The burned-area record misses fires under about 10 ha and most grass and farm fires.
Few fires near Cobble Hill: 0% within 5 km, 0.1% within 25 km
Fires mapped since 1986 around where Cobble Hill’s residents live, and the fuel next to their homes.
Next to the typical Canadian town (0.000% a year), Cobble Hill’s 0.003% is in the low band.
Fire has stayed at least 9.2 km from Cobble Hill’s homes since 1986.
The nearer ring around Cobble Hill is less wooded (47% forest fuel) than the land out to 25 km (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 Cobble Hill (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.
The low band takes in 92% of Canada’s 2,610 towns, Cobble Hill among them, though its rate is above zero; 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.
The flood map inventory lists nothing for Cobble Hill
Flood studies whose area touches Cobble Hill, from NRCan’s inventory, each linked to its owner.
Nationally, Cobble Hill has no listed flood study; the municipality is the place to ask.
Towns with a flood study on file
Cobble Hill has no flood study on file, though 76% of towns in British Columbia do (Canada: 58%).
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 Cobble Hill’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.”
High seismic risk in Cobble Hill: $0.68 per $1,000 of buildings a year
NRCan’s seismic risk model: the damage shaking is expected to do to buildings each year, on average over many years.
At $0.68 per $1,000, Cobble Hill carries roughly 22.6 times the typical Canadian town’s earthquake risk ($0.030).
Shaking damage a year per $1,000 of building value
At $0.68, Cobble Hill is above the typical town in British Columbia ($0.36); Duncan has the most 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.
Cobble Hill is in the top tenth of Canada’s 2,611 towns for earthquake risk; 0.7% rank higher.
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 Cobble Hill 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 runs low around Cobble Hill: 0.9% of tested homes over the guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline. · Area-wide: radon tests, counted over the Central Vancouver Island health region
Fewer homes than usual test high around Cobble Hill: 0.9% against 6.6% for the typical Canadian town.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Radon runs lower around Cobble Hill than in most towns in British Columbia: 0.9% against 1.8%.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
The quietest radon band, under 5%, holds 37% of Canada’s 2,611 towns and Cobble Hill; 63% sit 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.
A low area share in Cobble Hill doesn’t clear a house, nor does a high one condemn it: test.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Where to get warnings in Cobble Hill
Environment and Climate Change Canada issues the weather alerts for Cobble Hill; 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 Cobble Hill 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 Cobble Hill
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Cobble Hill | Low | $0.68 | 0.9% | None listed |
| Cowichan Bay 3,713 · 5.6 km | Low | $1.08 | 0.9% | Yes |
| Electoral Area A, Cowichan Valley 5,156 · 6.0 km | Low | $0.75 | 0.9% | Yes |
| Shawnigan 9,903 · 7.0 km | Low | $0.57 | 0.9% | Yes |
| North Saanich 12,986 · 11 km | Low | $0.73 | 1.8% | Yes |
| Cowichan 2,509 · 12 km | Low | $0.72 | 0.9% | Yes |
| Electoral Area E, Cowichan Valley 4,482 · 12 km | Low | $0.83 | 0.9% | Yes |
Shawnigan burns a little more than Cobble Hill, 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 Cobble Hill faces
What to do about the hazards Cobble Hill 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?
- Ask the municipality for flood maps.
- Are flood and wildfire insured?
- Is earthquake cover included?
What this data can and can’t tell you
- Flood studies aren’t flood zones. Flood studies cover areas of every size, which is why the page lists them for Cobble Hill without grading them.
- Wildfire counts one way. For Cobble Hill, wildfire means how much nearby land burned in the past forty years, a one-way input that can pull Risk down and nothing more.
- Earthquakes are modelled. Seismic risk is NRCan’s model of yearly building losses from shaking, averaged over many years and given for Cobble Hill’s census subdivision (a neighbourhood shows its city’s).
- Radon is a survey. Radon figures pool the survey’s home tests by area: postal areas once their boundaries arrive, the 2007 health region around Cobble Hill until then.
Questions about flooding and hazards in Cobble Hill
Is Cobble Hill at risk of wildfire?
Less than most of Canada: 0.1% of the land within 25 km of Cobble Hill has burned since 1986, the last in 2022, a low band that leaves Risk alone.
How is Cobble Hill’s Hazard risk Grade worked out?
Cobble Hill grades B− for hazard risk, from earthquakes and radon, with wildfire counted only where it lowers the grade.
How big is the earthquake risk in Cobble Hill?
About $0.68 a year per $1,000 of building value, NRCan’s long-run expectation for Cobble Hill.
Is radon a problem in Cobble Hill?
In Health Canada’s survey, 0.9% of 109 homes tested in Cobble Hill’s area were above 200 Bq/m³, though only a test tells you about one house.
Does Cobble Hill flood?
Nothing is listed for Cobble Hill on the national inventory (0); local maps may still exist with the municipality.
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).