Photo: Amakuha · CC BY 4.0A flood study covers Glebe-Dows Lake: 1 on the national inventory, the newest from Rideau Valley Conservation Authority
Wildfire barely registers for Glebe-Dows Lake, at 0% of the land within 25 km since 1986 (0.000% a year). Seismic risk runs high: $0.15 of expected damage per $1,000 of buildings a year, the typical town $0.030. Radon is about average around Glebe-Dows Lake: 6.2% of tested homes in the survey area topped the guideline, against 6.6% for the typical town. Hazard risk gives Glebe-Dows Lake a grade of C+, from earthquakes and radon alone.
What stands out about Glebe-Dows Lake’s hazards
Four national sources, each read for Glebe-Dows Lake: earthquakes, radon, past fires and flood studies.
What Glebe-Dows Lake faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Glebe-Dows Lake grades C+ for hazard risk
Earthquake risk and radon make Glebe-Dows Lake’s grade; wildfire can only lower it, never raise it, and flood studies are listed but not scored.
Its place: #703 of 866 in Ontario and #1,894 of 2,589 Canadian towns.
How sure: The seismic figure is a long-run average from NRCan’s model, not a prediction. The radon share rests on 64 home tests in the survey area, so a few homes move it. Small fires and grass fires are largely missing from the national burned-area record.
Wildfire is rare near Glebe-Dows Lake: 0% of the land within 25 km burned since 1986, 0% within 5 km
Past fire around Glebe-Dows Lake’s homes, from the national burned-area record, with the fuel within 5 km.
With 0.000% burned a year, Glebe-Dows Lake is among the many low-band places (the typical Canadian town 0.000%).
Glebe-Dows Lake’s homes have had no fire within 5 km since 1986; the closest was 19 km away.
7.7% of the land within 25 km of Glebe-Dows Lake is forest fuel, yet only 0.3% within 5 km of its homes.
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 Glebe-Dows Lake 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.
Most of the country’s 2,610 towns are low-band (92%, against 7.5% above); around Glebe-Dows Lake, 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.
Rideau Valley Conservation Authority has mapped flooding for Glebe-Dows Lake (1 study)
What Canada’s Flood Map Inventory lists for Glebe-Dows Lake: who studied flooding and where to see their maps.
The flood study touching Glebe-Dows Lake is Rideau Valley Conservation Authority’s, dated 2016; its own map shows the zones street by street.
| Study | By | Year | Status |
|---|---|---|---|
| Rideau River, Hogs Back to Rideau Falls | Rideau Valley Conservation Authority | 2016 | final |
Towns with a flood study on file
69% of towns in Ontario have a flood study, more than Canada’s 58%; Glebe-Dows Lake has one too.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
The grade leaves flood out, since a study area says nothing about how many of Glebe-Dows Lake’s homes are at risk.
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.
Shaking is Glebe-Dows Lake’s costliest hazard: $0.15 a year per $1,000
Expected yearly building losses from earthquakes, from Natural Resources Canada’s model.
Glebe-Dows Lake’s $0.15 is about 5 times the typical town’s $0.030: it sits in one of Canada’s more active seismic zones.
Nobody publishes earthquake risk for Glebe-Dows Lake alone, so this card uses the figure for the city of Ottawa.
Shaking damage a year per $1,000 of building value
Above the middle in Ontario: Glebe-Dows Lake’s $0.15 against a median of $0.043, with Alexandria highest 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.
More earthquake risk than most: only 15% of Canada’s 2,611 towns are above Glebe-Dows Lake.
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).
The model counts damage to Glebe-Dows Lake’s buildings and their occupants from shaking only: not liquefaction, landslides, tsunami or fires after a quake.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean).
6.2% of homes tested around Glebe-Dows Lake are over the radon guideline
Long-term radon tests in homes across the survey area, against Health Canada’s guideline.
Around Glebe-Dows Lake, 6.2% of tested homes topped the guideline, near the typical Canadian town’s 6.6%. For radon tests, the only official count covers all of the City of Ottawa Health Unit, Glebe-Dows Lake included.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
The median in Ontario is 4% over 200 Bq/m³; the survey area around Glebe-Dows Lake has 6.2%.
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Between 5% and 10% of tests over the guideline: Glebe-Dows Lake, and 37% of Canada’s 2,611 towns; 26% 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.
The survey sampled homes around Glebe-Dows Lake; it can’t tell you your basement’s level.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Weather and fire alerts for Glebe-Dows Lake
Environment and Climate Change Canada issues the weather alerts for Glebe-Dows Lake; 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. |
In fire season, check CWFIS for danger and active fires around Glebe-Dows Lake, and listen to local authorities for orders.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
Hazards in the places around Glebe-Dows Lake
Wildfire band, earthquake risk, radon and flood studies for each place nearby.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Glebe-Dows Lake | Low | $0.15 | 6.2% | Yes |
| Centretown 32,035 · 1.4 km | Low | $0.15 | 6.2% | Yes |
| Old Ottawa South 6,704 · 1.4 km | Low | $0.15 | 6.2% | Yes |
| West Centretown 8,560 · 1.6 km | Low | $0.15 | 6.2% | Yes |
| Old Ottawa East 8,308 · 1.7 km | Low | $0.15 | 6.2% | Yes |
| Civic Hospital 6,091 · 2.0 km | Low | $0.15 | 6.2% | None listed |
| Alta Vista 8,387 · 2.7 km | Low | $0.15 | 6.2% | Yes |
Centretown burns a little more than Glebe-Dows Lake, in the same low band (low here).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Glebe-Dows Lake faces
Practical steps for Glebe-Dows Lake’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.
- Drop, cover and hold on.
- Strap the water heater down.
- Keep 72 hours of supplies.
- Has it had a radon test?
- Check the address on the flood map.
- Are flood and wildfire insured?
- Is earthquake cover included?
What this data can and can’t tell you
- Earthquakes are modelled. NRCan models what earthquakes would cost buildings each year on average, subdivision by subdivision; Glebe-Dows Lake’s figure is its subdivision’s.
- Wildfire counts one way. Wildfire is read from the national burned-area record around Glebe-Dows Lake’s homes since 1986, a history of fire that may lower Risk but never raises it.
- 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 Glebe-Dows Lake floods.
- 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 Glebe-Dows Lake sits in.
Questions about flooding and hazards in Glebe-Dows Lake
How is Glebe-Dows Lake’s Hazard risk Grade worked out?
Hazard risk gives Glebe-Dows Lake C+, weighing earthquakes and radon and counting wildfire only against it.
Is Glebe-Dows Lake at risk of wildfire?
Not much by Canadian standards: Glebe-Dows Lake’s band is low, with 0% of the land within 25 km burned since 1986 (last in 2014), so wildfire doesn’t change its grade.
Is radon a problem in Glebe-Dows Lake?
6.2% of the 64 homes Health Canada tested around Glebe-Dows Lake topped the guideline; your own house needs its own test.
How big is the earthquake risk in Glebe-Dows Lake?
In NRCan’s seismic model, Glebe-Dows Lake’s buildings lose $0.15 per $1,000 of value in an average year.
Does Glebe-Dows Lake flood?
Glebe-Dows Lake’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).