Photo: Laslovarga · CC BY-SA 3.0A flood study covers Hamilton: 10 on the national inventory, the newest from Hamilton Conservation Authority
Wildfire barely registers for Hamilton, at 0% of the land within 25 km since 1986 (0.000% a year). Earthquake risk in Hamilton is ordinary: NRCan’s model puts building losses at $0.044 a year per $1,000 of value, close to the typical town’s $0.030. Hamilton’s survey area, 5% over the radon guideline, is close to the typical town’s 6.6%.
What stands out about Hamilton’s hazards
Four national sources, each read for Hamilton: earthquakes, radon, past fires and flood studies.
What Hamilton faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
No Hazard risk grade for Hamilton yet
Seismic risk and radon set Hamilton’s grade, wildfire can drag it down, and flood mapping stays out of it.
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.
Little of the land around Hamilton has burned: 0% within 5 km, 0% within 25 km since 1986
Fires mapped since 1986 around where Hamilton’s residents live, and the fuel next to their homes.
The yearly burn rate around Hamilton is 0.000%, low beside 0.000% for the typical Canadian town.
Little near Hamilton’s homes can carry a forest fire; only 3.1% of the land within 5 km is forest fuel, and 3.1% 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 872
Sioux Lookout has the highest burn rate in Ontario, 0.16% a year; around Hamilton, as around 639 of the 872 towns, it rounds to 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 Hamilton, 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.
Hamilton is on the flood map inventory: 10 studies, latest by Hamilton Conservation Authority
Flood studies whose area touches Hamilton, from NRCan’s inventory, each linked to its owner.
10 studies on the inventory touch Hamilton, the newest Hamilton Conservation Authority’s from 2025, and their areas can be large, so they say maps exist, not that the town floods.
| Study | By | Year | Status |
|---|---|---|---|
| Red Hill Creek | Hamilton Conservation Authority | 2025 | final |
| Floodplain Mapping Update in the Towns of Grimsby and Lincoln | Niagara Peninsula Conservation Authority | 2021 | final |
| Halton Shoreline Flood Hazard | Conservation Halton | 2020 | final · not public |
| Welland River | Niagara Peninsula Conservation Authority | 2018 | final |
| Grand River Regulatory Floodplain | Grand River Conservation Authority | 2018 | final |
| Twenty Mile Creek | Niagara Peninsula Conservation Authority | 2007 | final |
| Sinkhole Creek | Niagara Peninsula Conservation Authority | 2006 | final |
| Forty Mile Creek | Niagara Peninsula Conservation Authority | 1998 | final |
2 more studies on the inventory touch Hamilton.
Towns with a flood study on file
Hamilton is one of the 69% of towns in Ontario with a flood study on file; across Canada it is 58%.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
The studies touching Hamilton lean recent: 3 of 8 date from the 2020s, the first from the 1990s.
Study dates as the NRCan inventory lists them, one count per study touching Hamilton.
Flood studies don’t enter the grade; they are listed so you can open the official map for Hamilton.
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 Hamilton: $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.
Nothing unusual about Hamilton’s ground: $0.044 against a typical $0.030, 1.5 times.
Shaking damage a year per $1,000 of building value
Shaking damage around Hamilton runs at $0.044 a year, near the $0.043 of the typical town in Ontario; Alexandria has $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.
Hamilton sits above most of Canada’s 2,611 towns on earthquake risk; 32% are 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).
The loss is to Hamilton’s buildings alone, from ground shaking; infrastructure and secondary hazards are left out.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean).
Radon about average around Hamilton: 5% over the guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline. · Shared with the rest of the City of Hamilton Health Unit: radon tests
At 5% over the guideline, the area around Hamilton is about level with the typical Canadian town’s 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
More homes top the guideline around Hamilton (5%) than in the typical town in Ontario (4%).
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Radon tops the guideline in a modest share of homes around Hamilton, a band holding 37% of Canada’s 2,611 towns; 26% rank above.
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 Hamilton 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).
Weather and fire alerts for Hamilton
Alerts for Hamilton 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. |
Fire danger and active fires near Hamilton are mapped daily by the Canadian Wildland Fire Information System; evacuation orders come from the municipality or province.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
Hazards in the places around Hamilton
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Hamilton | Low | $0.044 | 5% | Yes |
| Inch Park 4,065 · 0.4 km | Low | $0.044 | 5% | None listed |
| Eastmount 4,496 · 0.6 km | Low | $0.044 | 5% | None listed |
| Hill Park 3,262 · 1.0 km | Low | $0.044 | 5% | None listed |
| Burkholme 3,580 · 1.1 km | Low | $0.044 | 5% | None listed |
| Centremount 4,053 · 1.4 km | Low | $0.044 | 5% | None listed |
| St. Clair 3,201 · 1.5 km | Low | $0.044 | 5% | None listed |
Hamilton’s low band tops its neighbours; Inch Park is next (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Hamilton faces
Practical steps for Hamilton’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
- 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 Hamilton.
- Earthquakes are modelled. NRCan models what earthquakes would cost buildings each year on average, subdivision by subdivision; Hamilton’s figure is its subdivision’s.
- Radon is a survey. About 14,000 homes were tested across Canada in 2009–2011, and the share over the guideline for Hamilton is its health region’s, the survey’s design unit.
- Wildfire counts one way. Wildfire is read from the national burned-area record around Hamilton’s homes since 1986, a history of fire that may lower Risk but never raises it.
Questions about flooding and hazards in Hamilton
How big is the earthquake risk in Hamilton?
Expected earthquake damage in Hamilton comes to $0.044 a year for each $1,000 that buildings are worth.
Is radon a problem in Hamilton?
The area’s survey found 5% of 100 tested homes above Health Canada’s guideline, so a three-month test is worth doing in Hamilton.
Is Hamilton at risk of wildfire?
The burned-area record shows next to nothing around Hamilton (0% within 25 km since 1986), so its band is low.
Does Hamilton flood?
There is flood mapping for Hamilton on the national inventory, each study linked to its owner’s map, none of them graded.
How is Hamilton’s Hazard risk Grade worked out?
Not yet: Canada’s grades come with its first grading run, when Risk will weigh earthquakes and radon in Hamilton, with wildfire able only to lower it.
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).