Home records, explained › Water and flooding
Is the home in a basement flooding study area, and what kind of sewer serves the street?
Toronto publishes the boundaries of its basement flooding study areas, the neighbourhoods where the City is studying or building relief sewers after past flooding. Ottawa publishes its water and wastewater network, which shows where combined sewers (one pipe for sewage and rain) remain.
Report check: Basement flooding and sewers. Entry reviewed 20 Oct 2026; each source below shows its own data date.
How a report shows itsample, made-up home
Inside Basement Flooding Study Area 12. The street has a separated sewer.
- Study area
- Area 12 (study complete)
- Sewer type on this street
- Separated (storm and sanitary)
Where we read it
- Toronto
- Ottawa
- Hamilton
- Guelph
- Other Ontario
the town's own records– not in our reports there yet
Published byCity of TorontoCity of Ottawa
What the record is
A study area is a record of where basement flooding has been reported widely enough for the City to investigate, not a record of flooding at any one house. Combined sewers are the older design that can back up in heavy rain; most cities have separated most of theirs and publish the rest.
In Toronto the report line names the study area the lot sits in, if any. In Ottawa it says whether a combined sewer runs near the address. Other cities don't publish either record as open data, so the line says where to ask (the City's water or sewer department, usually through 311).
Where it runs
What the report reads for this check depends on what each municipality publishes.
What we read in each town5 towns, each with its source and date
| City | What the report reads |
|---|---|
| Toronto |
|
| Ottawa |
|
| Hamilton | Not in our reports here yet. City of Hamilton doesn't publish an open map of basement flooding or sewer type for this address. Its water or sewer department (often through 311) can say whether the street has combined sewers or a basement flooding program. City of Hamilton |
| Guelph | Not in our reports here yet. City of Guelph doesn't publish an open map of basement flooding or sewer type for this address. Its water or sewer department (often through 311) can say whether the street has combined sewers or a basement flooding program. City of Guelph |
| Other Ontario | Not in our reports here yet. The municipality doesn't publish an open map of basement flooding or sewer type for this address. Its water or sewer department (often through 311) can say whether the street has combined sewers or a basement flooding program. List of Ontario municipalities |
Sources
- City of Toronto Basement Flooding Study Areas: data date Feb 2026
- City of Ottawa Water and Wastewater Infrastructure (combined sewers): data date 2026
Contains information licensed under the Open Government Licence – City of Ottawa. Contains information licensed under the Open Government Licence – Toronto.
Check one address
This check is in the full report, with the other 54 checks, for any Ontario home.
Public-record information, not legal, financial, insurance or inspection advice. Records change and can be incomplete, and this page describes the records, not any particular home. Spotted an error, or have a question about this record? Email [email protected]; we answer from the record, and corrections are listed on the guide index. What we cover, city by city.