Photo: JFVoll · CC BY-SA 3.0Hazard risk in Waterloo is lower than in 85% of Canadian towns
Since 1986 almost nothing has burned near Waterloo: 0% of the land within 25 km, or 0.000% a year. For earthquakes Waterloo is middling, $0.019 a year per $1,000 against $0.030 for the typical town. Radon is lower than usual: 4% of tested homes in the survey area topped the guideline, against 6.6% for the typical town. Hazard risk gives Waterloo a grade of A, from earthquakes and radon alone.
What stands out about Waterloo’s hazards
For Waterloo, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Waterloo faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Waterloo grades A for hazard risk
Seismic risk and radon set Waterloo’s grade, wildfire can drag it down, and flood mapping stays out of it.
Its place: #228 of 866 in Ontario and #570 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.
Little of the land around Waterloo has burned: 0% within 5 km, 0% within 25 km since 1986
Fires mapped since 1986 around where Waterloo’s residents live, and the fuel next to their homes.
Waterloo burns at 0.000% a year, low against 0.000% for the typical Canadian town.
With 2.9% forest fuel within 5 km and 3% within 25 km, the land around Waterloo gives a fire little to burn.
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
Of the 871 towns in Ontario, 638 have a burn rate that rounds to zero, Waterloo among them; Sioux Lookout leads at 0.16% a year.
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 holds 92% of Canada’s 2,610 towns, and Waterloo sits at its very bottom; only 7.5% are above it.
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.
A flood study covers Waterloo, from Grand River Conservation Authority: 1 on the inventory
Flood studies whose area touches Waterloo, from NRCan’s inventory, each linked to its owner.
A 2018 study by Grand River Conservation Authority covers Waterloo, and its map, not the inventory, shows the zones.
| Study | By | Year | Status |
|---|---|---|---|
| Grand River Regulatory Floodplain | Grand River Conservation Authority | 2018 | final |
Towns with a flood study on file
Waterloo 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.
Nothing here counts toward Risk; the studies are pointers to the maps their owners keep for Waterloo.
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 Waterloo: $0.019 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 $0.019 per $1,000, Waterloo’s earthquake risk is about the typical Canadian town’s ($0.030; 0.6 times).
Shaking damage a year per $1,000 of building value
Waterloo’s $0.019 sits under the median in Ontario, $0.043, and well under Alexandria’s $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.
Earthquakes cost less around Waterloo than in 66% of Canada’s 2,611 towns.
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 Waterloo 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 Waterloo: 4% of tested homes over the guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline. · Measured across the Waterloo Health Unit: radon tests
At 4% over the guideline, the area around Waterloo is under the typical Canadian town’s 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Around Waterloo, 4% of tests topped the guideline, about the same as 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.
Under 5% puts Waterloo with 37% of Canada’s 2,611 towns; 63% have more high tests.
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 Waterloo 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 Waterloo
Environment and Climate Change Canada issues the weather alerts for Waterloo; 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. |
In fire season, check CWFIS for danger and active fires around Waterloo, and listen to local authorities for orders.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
Hazards in the places around Waterloo
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Waterloo | Low | $0.019 | 4% | Yes |
| Westmount 5,048 · 3.3 km | Low | $0.022 | 4% | Yes |
| Cherry Hill 6,304 · 3.4 km | Low | $0.022 | 4% | Yes |
| Mt. Hope Huron Park 5,174 · 3.6 km | Low | $0.022 | 4% | Yes |
| Fairfield 3,497 · 3.7 km | Low | $0.022 | 4% | Yes |
| Victoria Hills 10,760 · 3.9 km | Low | $0.022 | 4% | Yes |
| Victoria Park 3,574 · 4.4 km | Low | $0.022 | 4% | Yes |
Fire is no heavier anywhere nearby than around Waterloo (low), with Westmount next at low.
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Waterloo faces
Practical steps for Waterloo’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
- 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 Waterloo.
- 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 Waterloo floods.
- Earthquakes are modelled. The earthquake figure is an expected loss, not a forecast, worked out by NRCan for each census subdivision, Waterloo’s included.
- 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 Waterloo sits in.
Questions about flooding and hazards in Waterloo
Does Waterloo flood?
Waterloo’s area has been studied for flooding, and the owner’s map shows which streets lie in a zone; the grade leaves flood out.
Is Waterloo at risk of wildfire?
The burned-area record shows next to nothing around Waterloo (0% within 25 km since 1986), so its band is low.
How big is the earthquake risk in Waterloo?
About $0.019 a year per $1,000 of building value, NRCan’s long-run expectation for Waterloo.
Is radon a problem in Waterloo?
The area’s survey found 4% of 101 tested homes above Health Canada’s guideline, so a three-month test is worth doing in Waterloo.
How is Waterloo’s Hazard risk Grade worked out?
Waterloo grades A for hazard risk, from earthquakes and radon, with wildfire counted only where it lowers the grade.
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).