Photo: JFVoll · CC BY-SA 4.0A flood study covers Colborne: 1 on the national inventory, the newest from Conservation Halton
Around Colborne, wildfire is practically absent from the record: 0% within 25 km since 1986, 0.000% a year. Seismic risk in Colborne sits near the middle: $0.044 of expected damage per $1,000 of buildings a year, the typical town $0.030. Radon around Colborne is ordinary for Canada: 5% of tested homes over the guideline (6.6% typical). Hazard risk gives Colborne a grade of B+, from earthquakes and radon alone.
What stands out about Colborne’s hazards
For Colborne, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Colborne faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Colborne grades B+ for hazard risk
For Colborne, Risk will be the average of earthquakes and radon, with wildfire added only if it makes the average worse.
Its place: #494 of 866 in Ontario and #1,255 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 Colborne: 0% within 5 km, 0% within 25 km
Fires mapped since 1986 around where Colborne’s residents live, and the fuel next to their homes.
At 0.000% of the land a year, Colborne’s burn rate is in the low band; the typical Canadian town sees 0.000%.
Little near Colborne’s homes can carry a forest fire; only 2.3% of the land within 5 km is forest fuel, and 4% 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 Ontario · highest of 871
Among the 871 towns in Ontario, Sioux Lookout burns fastest (0.16% a year); Colborne is with the 638 near zero.
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.
Most of the country’s 2,610 towns are low-band (92%, against 7.5% above); around Colborne, burning rounds to zero.
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.
Colborne is on the flood map inventory: 1 study, by Conservation Halton
Flood studies whose area touches Colborne, from NRCan’s inventory, each linked to its owner.
A 2020 study by Conservation Halton covers Colborne, and its map, not the inventory, shows the zones.
| Study | By | Year | Status |
|---|---|---|---|
| Halton Shoreline Flood Hazard | Conservation Halton | 2020 | final · not public |
Towns with a flood study on file
69% of towns in Ontario have a flood study, more than Canada’s 58%; Colborne 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 Colborne’s 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.
Expected shaking damage in Colborne: $0.044 a year per $1,000
NRCan’s seismic risk model: the damage shaking is expected to do to buildings each year, on average over many years.
1.5 times the typical $0.030: Colborne’s $0.044 is ordinary.
Figures for earthquake risk are published for the city of Hamilton as a whole, not for Colborne alone.
Shaking damage a year per $1,000 of building value
Neither high nor low in Ontario: Colborne’s $0.044 sits by the median of $0.043, while Alexandria reaches $0.21.
NRCan seismic risk model (2022): mean yearly building loss per $1,000 of value; medians of towns of 2,500 people or more.
32% of Canada’s 2,611 towns expect more shaking damage than Colborne, which places it in the upper third.
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 Colborne 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).
5% of homes tested around Colborne are over the radon 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 City of Hamilton Health Unit
5% of tested homes around Colborne were over the guideline, much like the typical Canadian town at 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
The median in Ontario is 4% over 200 Bq/m³; the survey area around Colborne has 5%.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Between 5% and 10% of tests over the guideline: Colborne, and 37% of Canada’s 2,611 towns; 26% are 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.
Neighbouring homes in Colborne can differ a lot; only a long-term test tells you about yours.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Where to get warnings in Colborne
Environment and Climate Change Canada issues the weather alerts for Colborne; 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 Colborne 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 Colborne
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Colborne | Low | $0.044 | 5% | Yes |
| Golf Course 3,741 · 2.4 km | Low | $0.044 | 5% | None listed |
| York Road 4,931 · 2.4 km | Low | $0.044 | 5% | Yes |
| Central Business Dis 6,127 · 2.5 km | Low | $0.044 | 5% | None listed |
| Turnball 6,312 · 3.1 km | Low | $0.044 | 5% | None listed |
| Ainslie Wood West 3,917 · 3.9 km | Low | $0.044 | 5% | None listed |
| Ainslie Wood East 3,112 · 4.6 km | Low | $0.044 | 5% | None listed |
None of the places around has more fire nearby than Colborne (low); Golf Course comes closest (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Colborne faces
Practical steps for Colborne’s 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
- Earthquakes are modelled. Seismic risk is NRCan’s model of yearly building losses from shaking, averaged over many years and given for Colborne’s census subdivision (a neighbourhood shows its city’s).
- Radon is a survey. Health Canada’s survey tested some 14,000 homes over three months; until postal-area boundaries are loaded, Colborne takes its 2007 health region’s share.
- Wildfire counts one way. For Colborne, 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. The flood inventory points to maps; it is incomplete and not the official source, so ask the municipality about any street in Colborne.
Questions about flooding and hazards in Colborne
Is Colborne at risk of wildfire?
Hardly at all on record: 0% of the land within 25 km of Colborne since 1986, a low band, though small grass fires aren’t mapped.
How is Colborne’s Hazard risk Grade worked out?
Hazard risk gives Colborne B+, weighing earthquakes and radon and counting wildfire only against it.
Does Colborne flood?
The inventory lists a study touching Colborne; whether a given street floods is on that map, not in the grade.
Is radon a problem in Colborne?
5% of the 100 homes Health Canada tested around Colborne topped the guideline; your own house needs its own test.
How big is the earthquake risk in Colborne?
About $0.044 a year per $1,000 of building value, NRCan’s long-run expectation for Colborne.
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).