Water hardness in Thunder Bay
46 mg/L soft
Tap water in Thunder Bay is soft: 46 mg/L (2.7 gpg · 2.6 °dH · 4.6 °fH).
Source: Ontario Ministry of the Environment, Conservation and Parks, Drinking Water Surveillance Program, Open Government Licence – Ontario (2015) · data checked 2026-10-21
Range across supply zones: 44–48 mg/L.
This figure is over 3 years old; hardness may have changed.
Thunder Bay draws water from Lake Superior through the Bare Point plant. Lake Superior is low in dissolved minerals, and the 2015 programme figure is 46.1 mg/L as CaCO3 (44.4 to 47.7). The water is soft, so scale is limited.
Health Canada: hardness above 200 mg/L is considered poor but tolerable; above 500 mg/L unacceptable.
Water data
| Total hardness | 46 mg/L |
|---|---|
| Utility | Bare Point Road Drinking Water System |
How Thunder Bay compares
- Tap water in Thunder Bay is 54 % softer than the median of the 254 cities we track in Canada (101 mg/L).
- By hardness it ranks 175 of 254 in Canada (1 = hardest); 31 % of these cities have softer water.
- In Ontario it is number 111 of 120 cities; the regional median is 124 mg/L.
- Nearest city with clearly harder water: Nipigon, 101 km away (72 mg/L).
Ranking of the hardest and softest water in Canada →
What it means at home
- Little or no limescale in kettles, water heaters or washing machines.
- Soap lathers easily; water does not dry skin or hair.
- Dishwasher: salt setting at minimum or off.
- No softener needed; a jug filter only changes taste.
How much salt will you use for softening?
No. Water this soft does not need softening.
Descale a coffee machine or kettle about every 6 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Thunder Bay
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 3 °dH |
| AEG / Electrolux | 1 |
| Beko | 1st |
| Hoover | S0 |
| LG | H0 |
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 Thunder Bay water hard or soft?
It is soft: 46 mg/L as CaCO₃ (2.7 gpg, 2.6 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Thunder Bay 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 Thunder Bay water?
2.7 gpg, equal to 2.6 °dH, 4.6 °fH or 46 mg/L calcium carbonate.
What dishwasher salt setting should I use in Thunder Bay?
For 46 mg/L (2.6 °dH) check your manufacturer's table: level 0–1, usually no salt.
Do I need a water softener in Thunder Bay?
No. With soft water a softener adds nothing.
Source
Source: Ontario Ministry of the Environment, Conservation and Parks, Drinking Water Surveillance Program, Open Government Licence – Ontario (2015). Method: figure published by the water supplier. Ontario Ministry of the Environment, Conservation and Parks, Drinking Water Surveillance Program, Open Government Licence – Ontario · Outdated figure? Tell us