Photo: P199 · Public domainMillbrook is on Canada’s flood inventory: 4 listed, led by Otonabee Region Conservation Authority
The national fire record shows next to nothing around Millbrook, 0% of the land within 25 km since 1986 (0.000% a year). NRCan expects $0.023 of shaking damage a year per $1,000 of buildings in Millbrook, near the typical $0.030. About as many homes carry radon around Millbrook as elsewhere, 8.9% over the guideline where the typical town has 6.6%. Millbrook grades B for hazard risk; wildfire is low here, so it earns no credit.
What stands out about Millbrook’s hazards
For Millbrook, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Millbrook faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Millbrook: B
Earthquake risk and radon make Millbrook’s grade; wildfire can only lower it, never raise it, and flood studies are listed but not scored.
Its place: #634 of 866 in Ontario and #1,465 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.
Wildfire is rare near Millbrook: 0% of the land within 25 km burned since 1986, 0% within 5 km
Fires mapped since 1986 around where Millbrook’s residents live, and the fuel next to their homes.
A burn rate of 0.000% a year keeps Millbrook in the low band (the typical Canadian town: 0.000%).
14% of the land within 5 km of Millbrook 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
Fire has taken almost none of the land around Millbrook, 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.
Like most of Canada’s 2,610 towns (92%), Millbrook is in the low band, with a burn rate of zero to three decimals; 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.
Flooding around Millbrook is mapped in 4 studies, the newest by Otonabee Region Conservation Authority
Flood studies whose area touches Millbrook, from NRCan’s inventory, each linked to its owner.
Otonabee Region Conservation Authority and others have studied flooding in areas that include Millbrook: 4 studies, the latest from 2025.
| Study | By | Year | Status |
|---|---|---|---|
| Byersville Creek Floodplain Mapping Study | Otonabee Region Conservation Authority | 2025 | final |
| Peterborough | Ontonabee Region Conservation Authority | 1991 | final · not public |
| Lakefield West | Ontonabee Region Conservation Authority | 1981 | final · not public |
| Millbrook Town Limits | Ontonabee Region Conservation Authority | 1978 | final · not public |
Towns with a flood study on file
Millbrook 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.
Flood mapping around Millbrook has come in steps: 4 studies from the 1970s to the 2020s.
Study dates as the NRCan inventory lists them, one count per study touching Millbrook.
Flood is shown here, never graded: a study says where a map exists, not how many of Millbrook’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.
Ordinary seismic risk in Millbrook: $0.023 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.
Earthquake losses in Millbrook, $0.023 per $1,000, are in line with the typical $0.030 (0.8 times).
Shaking damage a year per $1,000 of building value
Earthquake risk in Ontario peaks in Alexandria ($0.21); Millbrook, at $0.023, is below the median of $0.043.
NRCan seismic risk model (2022): mean yearly building loss per $1,000 of value; medians of towns of 2,500 people or more.
Neither high nor low for Canada: 54% of the 2,611 towns expect more damage than Millbrook.
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 Millbrook 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).
Some radon around Millbrook: 8.9% of area homes over the guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline. · Source area for radon tests: the Peterborough County-City Health Unit
Millbrook’s area sits close to the typical Canadian town: 8.9% over the guideline, against 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Around Millbrook, 8.9% of tests were over 200 Bq/m³ and 0.9% 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.
Radon tops the guideline in a modest share of homes around Millbrook, 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.
A low area share in Millbrook doesn’t clear a house, nor does a high one condemn it: test.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Where to get warnings in Millbrook
Environment and Climate Change Canada issues the weather alerts for Millbrook; 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 Millbrook 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 Millbrook
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Millbrook | Low | $0.023 | 8.9% | Yes |
| Otonabee-South Monaghan 8,084 · 16 km | Low | $0.029 | 8.9% | Yes |
| Peterborough 97,834 · 16 km | Low | $0.025 | 8.9% | Yes |
Otonabee-South Monaghan (low) has the heaviest fire record of Millbrook’s neighbours, and Millbrook (low) matches or beats it.
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Millbrook faces
Practical steps for Millbrook’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 Millbrook’s census subdivision (a neighbourhood shows its city’s).
- Wildfire counts one way. For Millbrook, wildfire means how much nearby land burned in the past forty years, a one-way input that can pull Risk down and nothing more.
- Radon is a survey. Radon figures pool the survey’s home tests by area: postal areas once their boundaries arrive, the 2007 health region around Millbrook until then.
- Flood studies aren’t flood zones. Flood studies cover areas of every size, which is why the page lists them for Millbrook without grading them.
Questions about flooding and hazards in Millbrook
Is Millbrook at risk of wildfire?
No meaningful wildfire history near Millbrook: 0% of nearby land since 1986, band low.
Does Millbrook flood?
A flood study covers Millbrook on Canada’s Flood Map Inventory; open the owner’s map to check a street, since flood isn’t graded.
Is radon a problem in Millbrook?
The area’s survey found 8.9% of 112 tested homes above Health Canada’s guideline, so a three-month test is worth doing in Millbrook.
How is Millbrook’s Hazard risk Grade worked out?
Millbrook’s Hazard risk grade is B, built on earthquakes and radon with a one-sided wildfire input.
How big is the earthquake risk in Millbrook?
About $0.023 a year per $1,000 of building value, NRCan’s long-run expectation for Millbrook.
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).