Photo: Nelro2 · Public domainA flood study covers Rockwood: 1 on the national inventory, the newest from Grand River Conservation Authority
The national fire record shows next to nothing around Rockwood, 0% of the land within 25 km since 1986 (0.000% a year). Shaking is about as much of a worry in Rockwood as in most places, at $0.022 a year per $1,000 of building value ($0.030 typical). Radon is higher than usual: 11% of tested homes in the survey area topped the guideline, against 6.6% for the typical town. Hazard risk gives Rockwood a grade of B−, from earthquakes and radon alone.
What stands out about Rockwood’s hazards
Four national sources, each read for Rockwood: earthquakes, radon, past fires and flood studies.
What Rockwood faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Rockwood: B−
Risk averages earthquakes and radon; wildfire joins only where it pulls the average down, so a town like Rockwood with little fire nearby would get no credit for it.
Its place: #663 of 866 in Ontario and #1,700 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.
Few fires near Rockwood: 0% within 5 km, 0% within 25 km
Fires mapped since 1986 around where Rockwood’s residents live, and the fuel next to their homes.
Low by Canadian standards: 0.000% of the land a year around Rockwood, 0.000% for the typical Canadian town.
11% of the land within 5 km of Rockwood is forest fuel, close to the 9.1% 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 871
Fire has taken almost none of the land around Rockwood, as for 638 of the 871 towns in Ontario; Sioux Lookout tops the list at 0.16%.
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 Rockwood 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 Rockwood, from Grand River Conservation Authority: 1 on the inventory
Flood studies whose area touches Rockwood, from NRCan’s inventory, each linked to its owner.
Grand River Conservation Authority holds the flood mapping that covers Rockwood (2018), linked below.
| Study | By | Year | Status |
|---|---|---|---|
| Grand River Regulatory Floodplain | Grand River Conservation Authority | 2018 | final |
Towns with a flood study on file
Mapping in Ontario reaches 69% of towns, Rockwood included, beside 58% across Canada.
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 Rockwood 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.
Earthquakes cost buildings in Rockwood $0.022 per $1,000 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 Rockwood’s ground: $0.022 against a typical $0.030, 0.7 times.
Shaking damage a year per $1,000 of building value
The typical town in Ontario expects $0.043 a year in shaking damage; Rockwood expects less, $0.022, and Alexandria the most, $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.
Rockwood’s earthquake risk lands near the centre of Canada’s range; 61% of the 2,611 towns 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).
Roads, pipes and bridges aren’t in Rockwood’s 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).
11% of homes tested around Rockwood are over the radon guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline. · Radon tests for the Wellington-Dufferin-Guelph Health Unit
A higher share than most: 11% of tested homes around Rockwood, the typical Canadian town 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Around Rockwood, 11% of tests were over 200 Bq/m³ and 2% over 600, against a median of 4% in Ontario.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
4.6% of Canada’s 2,611 towns have a higher share of homes over 200 Bq/m³ than Rockwood, in the 10–20% band with 22%.
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.
The share describes the area, not a house: in Rockwood as anywhere, test to be sure.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Weather and fire alerts for Rockwood
Alerts for Rockwood 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 Rockwood 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 Rockwood
The same four hazards for the places next door.
The neighbour with the most fire is Guelph (low), still no more than Rockwood (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Rockwood faces
What to do about the hazards Rockwood 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.
- 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. Shaking damage is modelled from the ground, the buildings and the odds of each quake, and published for whole subdivisions such as Rockwood’s.
- Wildfire counts one way. The wildfire figure is the share of land within 25 km of Rockwood’s homes burned each year from 1986 to 2025, past fire rather than a forecast, and it can only lower Risk.
- 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 Rockwood sits in.
- 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 Rockwood floods.
Questions about flooding and hazards in Rockwood
How big is the earthquake risk in Rockwood?
Expected earthquake damage in Rockwood comes to $0.022 a year for each $1,000 that buildings are worth.
Is Rockwood at risk of wildfire?
Very little by the national record: Rockwood’s band is low, with 0% of the land within 25 km burned since 1986, so wildfire doesn’t change its grade.
Is radon a problem in Rockwood?
In Health Canada’s survey, 11% of 99 homes tested in Rockwood’s area were above 200 Bq/m³, though only a test tells you about one house.
How is Rockwood’s Hazard risk Grade worked out?
Rockwood grades B− for hazard risk, from earthquakes and radon, with wildfire counted only where it lowers the grade.
Does Rockwood flood?
Rockwood’s area has been studied for flooding, and the owner’s map shows which streets lie in a zone; the grade leaves flood out.
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).