Photo: Earth Science and Remote Sensing Unit , Lyndon B. Johnson Space Center · Public domain20% of homes tested in Dundas’ area are above the radon guideline
Burn scars are few around Dundas, with 0.1% of the land within 25 km touched by fire since 1986 (0.002% a year). Shaking is about as much of a worry in Dundas as in most places, at $0.033 a year per $1,000 of building value ($0.030 typical). Dundas grades C− for hazard risk; wildfire is low here, so it earns no credit.
What stands out about Dundas’s hazards
Four national sources, each read for Dundas: earthquakes, radon, past fires and flood studies.
What Dundas faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Dundas grades C− for hazard risk
For Dundas, Risk will be the average of earthquakes and radon, with wildfire added only if it makes the average worse.
Its place: #25 of 60 in New Brunswick and #2,323 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.
Little of the land around Dundas has burned: 0% within 5 km, 0.1% within 25 km since 1986
Fires mapped since 1986 around where Dundas’ residents live, and the fuel next to their homes.
A burn rate of 0.002% a year keeps Dundas in the low band (the typical Canadian town: 0.000%).
Since 1986 the nearest fire to Dundas’ homes came within 12 km, never inside 5 km.
Within 5 km of Dundas, 59% of the land is forest fuel; widen the ring to 25 km and it is 69%.
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 New Brunswick · highest of 60
Dundas sits mid-table in New Brunswick: 30th of 60 towns, at 0.002% a year, well behind Tracadie (0.28%).
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.
Dundas 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.
Service New Brunswick - GeoNB has mapped flooding for Dundas (1 study)
Flood studies whose area touches Dundas, from NRCan’s inventory, each linked to its owner.
For Dundas the inventory points to Service New Brunswick - GeoNB’s 2020 study, whose map is the one to check.
| Study | By | Year | Status |
|---|---|---|---|
| Inland Flood Mapping in New Brunswick and Updated Sea-Level Rise and Flooding Estimates for New Brunswick Coastal Sections 2020 | Service New Brunswick - GeoNB | 2020 | final |
Towns with a flood study on file
Its flood study puts Dundas with 93% of towns in New Brunswick; Canada’s share is 58%.
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 Dundas 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.
Ordinary seismic risk in Dundas: $0.033 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.
Nothing unusual about Dundas’ ground: $0.033 against a typical $0.030, 1.1 times.
Shaking damage a year per $1,000 of building value
Dundas’ $0.033 is close to the median in New Brunswick, $0.036; St. Stephen is highest at $0.16.
NRCan seismic risk model (2022): mean yearly building loss per $1,000 of value; medians of towns of 2,500 people or more.
Neither high nor low for Canada: 48% of the 2,611 towns expect more damage than Dundas.
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 Dundas’ 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).
20% of homes tested around Dundas are over the radon guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline.
More homes than usual test high around Dundas: 20% against 6.6% for the typical Canadian town.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Dundas’ area, at 20%, is close to the median in New Brunswick (20%); 3.7% of its tests passed 600 Bq/m³.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
One test in ten or more tops the guideline around Dundas, as in 22% of Canada’s 2,611 towns; 4.6% go 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 Dundas 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). · Area behind the radon tests figures: the Region 1 health region
Weather and fire alerts for Dundas
Alerts for Dundas 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. |
Evacuation orders for Dundas come from the municipality or the province, while CWFIS maps fire danger every day.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
Hazards in the places around Dundas
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Dundas | Low | $0.033 | 20% | Yes |
| Cocagne 2,982 · 6.7 km | Low | $0.035 | 20% | Yes |
| Shediac 5,699 · 9.9 km | Low | $0.036 | 20% | Yes |
| Shediac 9,849 · 12 km | Low | $0.032 | 20% | Yes |
| Saint-Antoine 1,880 · 15 km | Low | $0.040 | 20% | None listed |
The fire record around Saint-Antoine is a touch heavier than Dundas’, 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 Dundas faces
Practical steps for Dundas’ hazards, most pressing first.
- 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.
- Clear needles and wood nearby.
- Keep a grab-and-go bag ready.
- In smoke, stay in; filter air.
- Has it had a radon test?
- Check the address on the flood map.
- Are flood and wildfire insured?
What this data can and can’t tell you
- Wildfire counts one way. The wildfire figure is the share of land within 25 km of Dundas’ homes burned each year from 1986 to 2025, past fire rather than a forecast, and it can only lower Risk.
- Earthquakes are modelled. Shaking damage is modelled from the ground, the buildings and the odds of each quake, and published for whole subdivisions such as Dundas’.
- 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 Dundas floods.
- 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 Dundas sits in.
Questions about flooding and hazards in Dundas
Is Dundas at risk of wildfire?
Not much by Canadian standards: Dundas’ band is low, with 0.1% of the land within 25 km burned since 1986 (last in 2025), so wildfire doesn’t change its grade.
How is Dundas’s Hazard risk Grade worked out?
Dundas grades C− for hazard risk, from earthquakes and radon, with wildfire counted only where it lowers the grade.
Is radon a problem in Dundas?
20% of the 107 homes Health Canada tested around Dundas topped the guideline; your own house needs its own test.
Does Dundas flood?
Dundas’ 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 Dundas?
About $0.033 a year per $1,000 of building value, NRCan’s long-run expectation for Dundas.
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).