Photo: Amakuha · CC BY 4.0A flood study covers Marmora: 1 on the national inventory, the newest from Crowe Valley Conservation Authority
Wildfire barely registers for Marmora, at 0% of the land within 25 km since 1986 (0.000% a year). For earthquakes Marmora is middling, $0.033 a year per $1,000 against $0.030 for the typical town. Radon is higher than usual: 12% of tested homes in the survey area topped the guideline, against 6.6% for the typical town. Marmora grades C+ for hazard risk; wildfire is low here, so it earns no credit.
What stands out about Marmora’s hazards
Four national sources, each read for Marmora: earthquakes, radon, past fires and flood studies.
What Marmora faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Marmora: C+
For Marmora, Risk will be the average of earthquakes and radon, with wildfire added only if it makes the average worse.
Its place: #819 of 866 in Ontario and #2,043 of 2,589 Canadian towns.
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 Marmora has burned: 0% within 5 km, 0% within 25 km since 1986
Past fire around Marmora’s homes, from the national burned-area record, with the fuel within 5 km.
A burn rate of 0.000% a year keeps Marmora in the low band (the typical Canadian town: 0.000%).
The closest burn since 1986 lies 17 km from Marmora’s homes, none within 5 km.
13% of the land within 5 km of Marmora is forest fuel, close to the 15% 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
Near-zero burning puts Marmora with 638 of the 871 towns in Ontario, far below Sioux Lookout 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.
Measured against 2,610 towns, Marmora is in the largest group, low (92%), and at its floor, while 7.5% rank 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.
Marmora is on the flood map inventory: 1 study, by Crowe Valley Conservation Authority
What Canada’s Flood Map Inventory lists for Marmora: who studied flooding and where to see their maps.
Crowe Valley Conservation Authority holds the flood mapping that covers Marmora (2024), linked below.
| Study | By | Year | Status |
|---|---|---|---|
| Crowe River FHIMP | Crowe Valley Conservation Authority | 2024 | under review · not public |
Towns with a flood study on file
Flood maps are common in Ontario: 69% of towns have one, against 58% nationally, and Marmora is among them.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
Listed, not scored: a flood study proves a map exists, not that Marmora floods.
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 Marmora $0.033 per $1,000 a year
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
With $0.033 of shaking damage a year per $1,000, Marmora is about even with the typical $0.030 (1.1 times).
Shaking damage a year per $1,000 of building value
Below the middle in Ontario: Marmora’s $0.033 against a median of $0.043; 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.
Middle of the pack: 48% of Canada’s 2,611 towns have more earthquake risk than Marmora.
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 Marmora’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).
Radon runs high around Marmora: 12% of tested homes over the guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline. · Measured across the Hastings and Prince Edward Counties Health Unit: radon tests
A higher share than most: 12% of tested homes around Marmora, the typical Canadian town 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Around Marmora, 12% 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.
Marmora is in the 10–20% band, with 22% of Canada’s 2,611 towns; only 4.6% 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.
One home in Marmora 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 Marmora
Alerts for Marmora 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 Marmora 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)
How Marmora’s neighbours compare on hazards
Wildfire band, earthquake risk, radon and flood studies for each place nearby.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Marmora | Low | $0.033 | 12% | Yes |
| Havelock 5,663 · 16 km | Low | $0.032 | 8.9% | Yes |
| Madoc 2,467 · 19 km | Low | $0.035 | 12% | None listed |
| Centre Hastings 5,170 · 19 km | Low | $0.034 | 12% | None listed |
The neighbour with the most fire is Havelock (low), still no more than Marmora (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Marmora faces
Practical steps for Marmora’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
- Radon is a survey. About 14,000 homes were tested across Canada in 2009–2011, and the share over the guideline for Marmora is its health region’s, the survey’s design unit.
- 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 Marmora.
- 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 Marmora’s.
- Wildfire counts one way. The wildfire figure is the share of land within 25 km of Marmora’s homes burned each year from 1986 to 2025, past fire rather than a forecast, and it can only lower Risk.
Questions about flooding and hazards in Marmora
Is Marmora at risk of wildfire?
Some, but Marmora’s low band (0% of nearby land burned since 1986, latest 2025) is short of the level that counts.
Does Marmora flood?
There is flood mapping for Marmora on the national inventory, each study linked to its owner’s map, none of them graded.
Is radon a problem in Marmora?
The area’s survey found 12% of 99 tested homes above Health Canada’s guideline, so a three-month test is worth doing in Marmora.
How big is the earthquake risk in Marmora?
NRCan’s model expects shaking to cost buildings in Marmora $0.033 a year for every $1,000 of their value, on average over many years.
How is Marmora’s Hazard risk Grade worked out?
Hazard risk gives Marmora C+, weighing earthquakes and radon and counting wildfire only against 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).