Water hardness in Le Sud-Ouest
123 mg/L hard
Tap water in Le Sud-Ouest is hard: 123 mg/L (7.2 gpg · 6.9 °dH · 12.3 °fH).
Source: Ville de Montréal, Sommaire annuel 2022 - qualité de l'eau potable Atwater/Charles-J.-Des-Baillets (2022) · data checked 2026-11-02
Range across supply zones: 113–131 mg/L.
This figure is over 3 years old; hardness may have changed.
Le Sud-Ouest is a Montréal borough served by the city's Atwater and Charles-J.-Des Baillets plants. Their 2022 annual summary gives an average total hardness of 123 mg/L as CaCO3, with a range of 113 to 131 mg/L. This is the latest figure we could verify. Moderately hard water leaves some scale on dishes and shower heads.
Health Canada: hardness above 200 mg/L is considered poor but tolerable; above 500 mg/L unacceptable.
Water data
| Total hardness | 123 mg/L |
|---|---|
| Utility | Ville de Montréal (usines Atwater et Charles-J.-Des-Baillets) |
How Le Sud-Ouest compares
- Tap water in Le Sud-Ouest is 21 % harder than the median of the 254 cities we track in Canada (101 mg/L).
- By hardness it ranks 93 of 254 in Canada (1 = hardest); 60 % of these cities have softer water.
- In Québec it is number 1 of 14 cities; the regional median is 86 mg/L.
- Nearest city with clearly softer water: Pointe-Claire, 18 km away (59 mg/L).
Ranking of the hardest and softest water in Canada →
What it means at home
- Fast scale on taps, shower screens and kettle; white spots on glassware.
- Water heater: efficiency loss and element failures within years if unprotected.
- Dry skin and dull hair after showering are common.
- Softener recommended; jug or reverse osmosis for drinking.
How much salt will you use for softening?
Recommended, especially with a heater or boiler: scale cuts efficiency and shortens its life.
Descale a coffee machine or kettle about every 2 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Le Sud-Ouest
| Brand | Setting for this water |
|---|---|
| Bosch | H01 |
| Miele | 7 °dH |
| AEG / Electrolux | 2 |
| Beko | 2nd |
| Hoover | S1 |
| LG | H2 |
From each brand's manual for the model family named in the source; your model may differ, so check its manual. All brands and how to change the setting →
FAQ
Is Le Sud-Ouest water hard or soft?
It is hard: 123 mg/L as CaCO₃ (7.2 gpg, 6.9 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Le Sud-Ouest safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Health Canada: hardness above 200 mg/L is considered poor but tolerable; above 500 mg/L unacceptable.
How many grains per gallon is Le Sud-Ouest water?
7.2 gpg, equal to 6.9 °dH, 12.3 °fH or 123 mg/L calcium carbonate.
What dishwasher salt setting should I use in Le Sud-Ouest?
For 123 mg/L (6.9 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Le Sud-Ouest?
Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.
Source
Source: Ville de Montréal, Sommaire annuel 2022 - qualité de l'eau potable Atwater/Charles-J.-Des-Baillets (2022). Method: figure published by the water supplier. Ville de Montréal, Sommaire annuel 2022 - qualité de l'eau potable Atwater/Charles-J.-Des-Baillets · Outdated figure? Tell us