Earthquake risk in Douglas runs 16 times the typical Canadian town’s: $0.47 per $1,000 a year
Little of the land around Douglas has burned: 0.1% within 25 km since 1986, or 0.002% a year. Radon is lower than usual: 0% of tested homes in the survey area topped the guideline, against 6.6% for the typical town. Douglas grades B for hazard risk, with wildfire counted against it.
What stands out about Douglas’s hazards
For Douglas, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Douglas faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Douglas: B
Risk averages earthquakes and radon; wildfire joins only where it pulls the average down, so a town like Douglas with little fire nearby would get no credit for it.
Its place: #59 of 254 in British Columbia and #1,520 of 2,589 Canadian towns.
How sure: The seismic figure is a long-run average from NRCan’s model, not a prediction. The radon share rests on 70 home tests in the survey area, so a few homes move it. The burned-area record misses fires under about 10 ha and most grass and farm fires.
Few fires near Douglas: 0% within 5 km, 0.1% within 25 km
Fires mapped since 1986 around where Douglas’ residents live, and the fuel next to their homes.
A burn rate of 0.002% a year keeps Douglas in the low band (the typical Canadian town: 0.000%).
No fire has burned within 5 km of Douglas’ homes since 1986; the nearest burn is 21 km away.
9.2% of the land within 5 km of Douglas is forest fuel, close to the 5.3% 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
Some fire is mapped around Douglas (0.002% a year), but it ranks only 230th 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.
Douglas 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.
City of Surrey has mapped flooding for Douglas (1 study)
Flood studies whose area touches Douglas, from NRCan’s inventory, each linked to its owner.
The flood study touching Douglas is City of Surrey’s, dated 2015; its own map shows the zones street by street.
| Study | By | Year | Status |
|---|---|---|---|
| Serpentine & Nicomekl River Climate Change Floodplain Review Phase 2 | City of Surrey | 2015 | final |
Towns with a flood study on file
76% of towns in British Columbia have a flood study, more than Canada’s 58%; Douglas has one too.
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 Douglas’ 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.”
Natural Resources Canada, Canada Flood Map Inventory; links go to each study’s owner.
High seismic risk in Douglas: $0.47 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 $0.47 per $1,000, Douglas carries roughly 15.7 times the typical Canadian town’s earthquake risk ($0.030).
Shaking damage a year per $1,000 of building value
At $0.47, Douglas 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.
Few of Canada’s 2,611 towns face more earthquake damage than Douglas: 1.6% 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).
Only shaking damage to buildings in Douglas is counted; landslides, liquefaction, tsunami and fire after a quake aren’t.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean). · Area behind the earthquake risk figures: the city of Surrey
Little radon around Douglas: 0% of area 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 Fraser South health region
At 0% over the guideline, the area around Douglas is under the typical Canadian town’s 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Radon runs lower around Douglas than in most towns in British Columbia: 0% against 1.8%.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Douglas 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.
Whatever Douglas’ area share, the reading that matters is your own home’s, over a winter.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Where to get warnings in Douglas
Environment and Climate Change Canada issues the weather alerts for Douglas; 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 Douglas 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 Douglas’ neighbours compare on hazards
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Douglas | Low | $0.47 | 0% | Yes |
| Grandview 16,947 · 4.2 km | Low | $0.47 | 0% | Yes |
| White Rock 25,057 · 4.4 km | Low | $0.60 | 0% | Yes |
| Semiahmoo Town Centre 13,381 · 4.5 km | Low | $0.47 | 0% | Yes |
| Sunnyside 16,784 · 5.3 km | Low | $0.47 | 0% | Yes |
| South Surrey 6,431 · 7.1 km | Low | $0.47 | 0% | Yes |
| Morgan Creek 8,084 · 7.2 km | Low | $0.47 | 0% | Yes |
White Rock burns a little more than Douglas, 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 Douglas faces
What to do about the hazards Douglas 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
- 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 Douglas sits in.
- Wildfire counts one way. Burned land within 25 km of where people live, averaged over 1986–2025 and checked for fuel near homes, is the measure; it looks back, not ahead, and only ever counts against Douglas.
- 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 Douglas floods.
- Earthquakes are modelled. The earthquake figure is an expected loss, not a forecast, worked out by NRCan for each census subdivision, Douglas’ included.
Questions about flooding and hazards in Douglas
How is Douglas’s Hazard risk Grade worked out?
Douglas grades B for hazard risk, from earthquakes and radon, with wildfire counted only where it lowers the grade.
Does Douglas flood?
Douglas’ area has been studied for flooding, and the owner’s map shows which streets lie in a zone; the grade leaves flood out.
How big is the earthquake risk in Douglas?
About $0.47 a year per $1,000 of building value, NRCan’s long-run expectation for Douglas.
Is Douglas at risk of wildfire?
Less than most of Canada: 0.1% of the land within 25 km of Douglas has burned since 1986, the last in 2016, a low band that leaves Risk alone.
Is radon a problem in Douglas?
In Health Canada’s survey, 0% of 70 homes tested in Douglas’ 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).