Photo: Earth Science and Remote Sensing Unit , Lyndon B. Johnson Space Center · Public domainHazard risk in Medway is lower than in 90% of Canadian towns
For Medway, wildfire history is close to nil: 0% of nearby land since 1986, 0.000% a year. Shaking is about as much of a worry in Medway as in most places, at $0.020 a year per $1,000 of building value ($0.030 typical). In Health Canada’s survey, just 1.8% of homes tested in the area exceeded 200 Bq/m³ (6.6% typical). Hazard risk gives Medway a grade of A, from earthquakes and radon alone.
What stands out about Medway’s hazards
For Medway, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Medway faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Medway grades A for hazard risk
For Medway, Risk will be the average of earthquakes and radon, with wildfire added only if it makes the average worse.
Its place: #43 of 866 in Ontario and #347 of 2,589 Canadian towns.
How sure: Earthquake losses are a model’s expectation over many years, not a forecast for any one. The burned-area record misses fires under about 10 ha and most grass and farm fires.
Few fires near Medway: 0% within 5 km, 0% within 25 km
Past fire around Medway’s homes, from the national burned-area record, with the fuel within 5 km.
In a typical year 0.000% of the land near Medway burns; the typical Canadian town sees 0.000%, and both are low.
Forest fuel is scarce around Medway: 0.4% of the land within 5 km, 0.4% 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
To three decimals the burn rate around Medway is zero, as for 638 of the 871 towns in Ontario, while Sioux Lookout reaches 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.
Most of the country’s 2,610 towns are low-band (92%, against 7.5% above); around Medway, 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.
No flood study is listed for Medway
What Canada’s Flood Map Inventory lists for Medway: who studied flooding and where to see their maps.
NRCan’s inventory is silent on Medway, so any flood map would be the municipality’s own.
Towns with a flood study on file
Flood maps are common in Ontario, 69% of towns against 58% nationally, but none in the inventory touches Medway.
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 Medway 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.”
Expected shaking damage in Medway: $0.020 a year per $1,000
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
0.7 times the typical $0.030: Medway’s $0.020 is ordinary.
Nobody publishes earthquake risk for Medway alone, so this card uses the figure for the city of London.
Shaking damage a year per $1,000 of building value
The typical town in Ontario expects $0.043 a year in shaking damage; Medway expects less, $0.020, 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.
Medway’s earthquake risk lands near the centre of Canada’s range; 64% 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).
For Medway 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).
Little radon around Medway: 1.8% of area homes over the guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline. · Shared with the rest of the Middlesex-London Health Unit: radon tests
Radon runs below the typical Canadian town (6.6%) in Medway’s area, at 1.8%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
The median in Ontario is 4% over 200 Bq/m³; around Medway it is 1.8%.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
63% of Canada’s 2,611 towns have a higher share of homes over 200 Bq/m³ than Medway’s band, which holds 37%.
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.
Health Canada advises testing every home, Medway’s included, whatever the area’s figure.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Where to get warnings in Medway
Alerts for Medway 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 Medway 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 Medway’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 |
|---|---|---|---|---|
| Medway | Low | $0.020 | 1.8% | None listed |
| Hyde Park 14,769 · 2.1 km | Low | $0.020 | 1.8% | None listed |
| Masonville 10,359 · 2.4 km | Low | $0.020 | 1.8% | None listed |
| West London 24,322 · 2.5 km | Low | $0.020 | 1.8% | None listed |
| Oakridge 16,247 · 3.6 km | Low | $0.020 | 1.8% | None listed |
| North London 9,584 · 3.7 km | Low | $0.020 | 1.8% | None listed |
| Sunningdale 21,645 · 4.0 km | Low | $0.020 | 1.8% | None listed |
None of the places around has more fire nearby than Medway (low); Hyde Park comes closest (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Medway faces
Practical steps for Medway’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?
- Ask the municipality for flood maps.
- 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 Medway.
- Earthquakes are modelled. Seismic risk is NRCan’s model of yearly building losses from shaking, averaged over many years and given for Medway’s census subdivision (a neighbourhood shows its city’s).
- Radon is a survey. About 14,000 homes were tested across Canada in 2009–2011, and the share over the guideline for Medway is its health region’s, the survey’s design unit.
- Wildfire counts one way. For Medway, wildfire means how much nearby land burned in the past forty years, a one-way input that can pull Risk down and nothing more.
Questions about flooding and hazards in Medway
How big is the earthquake risk in Medway?
NRCan’s model expects shaking to cost buildings in Medway $0.020 a year for every $1,000 of their value, on average over many years.
Is radon a problem in Medway?
1.8% of the 110 homes Health Canada tested around Medway topped the guideline; your own house needs its own test.
How is Medway’s Hazard risk Grade worked out?
Medway’s Hazard risk grade is A, built on earthquakes and radon with a one-sided wildfire input.
Is Medway at risk of wildfire?
Hardly at all on record: 0% of the land within 25 km of Medway since 1986, a low band, though small grass fires aren’t mapped.
Does Medway flood?
No study on Canada’s Flood Map Inventory covers Medway (0), which doesn’t mean it has never been mapped, so ask the municipality.
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).