Water hardness in Mississauga
Mississauga, Ontario tap water is moderately hard, drawn from lake ontario. Here is what it means at home, and the source.
What this means at home
Some kettle and showerhead scale over time, but most homes get by without a softener.
Mississauga is on the South Peel system, fed by Lake Ontario, which Peel Region reports at 120 to 130 mg/L and classes as moderately hard. Steady year to year, unlike the groundwater cities to the west.
You likely do not need a softener. A quick test kit confirms it for your own tap.
Mississauga water hardness questions
How hard is the water in Mississauga?
Mississauga's tap water is moderately hard, about 120 to 130 mg/L as calcium carbonate (7.0 to 7.6 grains per gallon), drawn from lake ontario. Figure from Region of Peel, last checked 2026-06-24.
Do I need a water softener in Mississauga?
Probably not. Mississauga water is moderately hard, so most homes get by without one. A simple test kit settles it if you are unsure.
Why is Mississauga's water moderately hard?
Mississauga is on the South Peel system, fed by Lake Ontario, which Peel Region reports at 120 to 130 mg/L and classes as moderately hard. Steady year to year, unlike the groundwater cities to the west.
Source
Source: Region of Peel, last checked 2026-06-24. Hardness varies by neighbourhood, season, and which well or plant serves your street, especially on groundwater systems. These are the municipal published figures as of the verified date, good for planning, not a substitute for a home test or your utility's current report.
Compare nearby verified figures: Brampton, Toronto, Hamilton. Or see every municipality.