Sherwood is on Canada’s flood inventory: 1 listed, led by Hamilton Conservation Authority
Wildfire barely registers for Sherwood, at 0% of the land within 25 km since 1986 (0.000% a year). Earthquake risk in Sherwood is ordinary: NRCan’s model puts building losses at $0.044 a year per $1,000 of value, close to the typical town’s $0.030. Radon around Sherwood is ordinary for Canada: 5% of tested homes over the guideline (6.6% typical). Sherwood grades B+ for hazard risk; wildfire is low here, so it earns no credit.
What stands out about Sherwood’s hazards
For Sherwood, from NRCan’s seismic model, Health Canada’s radon survey, the national burned-area record and the flood map inventory.
What Sherwood faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Sherwood: B+
Seismic risk and radon set Sherwood’s grade, wildfire can drag it down, and flood mapping stays out of it.
Its place: #494 of 866 in Ontario and #1,255 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.
Few fires near Sherwood: 0% within 5 km, 0% within 25 km
Past fire around Sherwood’s homes, from the national burned-area record, with the fuel within 5 km.
A burn rate of 0.000% a year keeps Sherwood in the low band (the typical Canadian town: 0.000%).
Forest fuel is scarce around Sherwood: 0.2% of the land within 5 km, 0.9% 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
Sioux Lookout has the highest burn rate in Ontario, 0.16% a year; around Sherwood, as around 638 of the 871 towns, it rounds to zero.
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%), Sherwood 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.
Sherwood is on the flood map inventory: 1 study, by Hamilton Conservation Authority
What Canada’s Flood Map Inventory lists for Sherwood: who studied flooding and where to see their maps.
For Sherwood the inventory points to Hamilton Conservation Authority’s 2025 study, whose map is the one to check.
| Study | By | Year | Status |
|---|---|---|---|
| Red Hill Creek | Hamilton Conservation Authority | 2025 | final |
Towns with a flood study on file
Flood maps are common in Ontario: 69% of towns have one, against 58% nationally, and Sherwood is among them.
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 Sherwood 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.
Expected shaking damage in Sherwood: $0.044 a year per $1,000
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
Sherwood’s $0.044 is close to the typical town’s $0.030 (1.5 times as much).
Sherwood doesn’t get its own earthquake risk figures; the ones here come from the city of Hamilton.
Shaking damage a year per $1,000 of building value
The median in Ontario is $0.043; Sherwood, at $0.044, is right beside it, and Alexandria tops the list at $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.
32% of Canada’s 2,611 towns expect more shaking damage than Sherwood, which places it in the upper third.
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).
Only shaking damage to buildings in Sherwood is counted; landslides, liquefaction, tsunami and fire after a quake aren’t.
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 Sherwood: 5% of area homes over the guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline.
Near the middle for radon: Sherwood’s area 5%, the typical Canadian town 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Sherwood’s area, at 5%, is above the median in Ontario (4%).
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
37% of Canada’s 2,611 towns share Sherwood’s band of 5 to 10%; 26% sit 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.
A low area share in Sherwood 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). · Area behind the radon tests figures: the City of Hamilton Health Unit
Where to get warnings in Sherwood
Alerts for Sherwood 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 Sherwood 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)
Hazards in the places around Sherwood
Wildfire band, earthquake risk, radon and flood studies for each place nearby.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Sherwood | Low | $0.044 | 5% | Yes |
| Huntington 5,024 · 0.7 km | Low | $0.044 | 5% | Yes |
| Hampton Heights 3,498 · 1.3 km | Low | $0.044 | 5% | None listed |
| Delta East 6,186 · 1.3 km | Low | $0.044 | 5% | None listed |
| Rosedale 3,070 · 1.3 km | Low | $0.044 | 5% | Yes |
| Raleigh 7,113 · 1.5 km | Low | $0.044 | 5% | None listed |
| Macassa 2,584 · 1.6 km | Low | $0.044 | 5% | None listed |
Sherwood’s low band tops its neighbours; Huntington is next (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Sherwood faces
Practical steps for Sherwood’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 Sherwood’s census subdivision (a neighbourhood shows its city’s).
- 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 Sherwood floods.
- Wildfire counts one way. For Sherwood, 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. The radon share comes from about 14,000 long-term home tests in 2009–2011, pooled for now by the 2007 health region Sherwood sits in.
Questions about flooding and hazards in Sherwood
Is radon a problem in Sherwood?
5% of the 100 homes Health Canada tested around Sherwood topped the guideline; your own house needs its own test.
Does Sherwood flood?
Sherwood’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 Sherwood at risk of wildfire?
No meaningful wildfire history near Sherwood: 0% of nearby land since 1986, band low.
How big is the earthquake risk in Sherwood?
NRCan’s model expects shaking to cost buildings in Sherwood $0.044 a year for every $1,000 of their value, on average over many years.
How is Sherwood’s Hazard risk Grade worked out?
Sherwood grades B+ 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).