Water hardness in Kalisz
280 mg/L very hard
Tap water in Kalisz is very hard: 280 mg/L (16.4 gpg · 15.7 °dH · 28 °fH).
Source: PWiK Kalisz, jakość wody I półrocze 2024 (2024) · data checked 2026-10-29
Range across supply zones: 262–418 mg/L.
4 supply zones — hardness varies by neighbourhood; the figure above is the median.
Hardness by district / supply zone
| mg/L | mg/L | ||
|---|---|---|---|
| SUW Fabryczna | 264 | 264 | very hard |
| SUW Lis | 262 | 262 | very hard |
| SUW Poznańska | 418 | 418 | very hard |
| SUW Warszawska | 296 | 296 | very hard |
PWiK Kalisz reports a median of 280 mg/L CaCO₃ across four zones, with values from 262 to 418 mg/L. This figure is based on a first-half 2024 report, so it is older than most entries and may have shifted since. Even the softest zone is well into the very hard category, so limescale on appliances is likely everywhere in the city.
Polish suppliers report total hardness in mg/L CaCO₃; the drinking-water regulation range is 60–500 mg/L.
Water data
| Total hardness | 280 mg/L |
|---|---|
| Utility | PWiK Sp. z o.o. w Kaliszu |
How Kalisz compares
- Tap water in Kalisz is 14 % harder than the median of the 91 cities we track in Poland (245 mg/L).
- By hardness it ranks 21 of 91 in Poland (1 = hardest); 77 % of these cities have softer water.
- In wielkopolskie it is number 4 of 5 cities; the regional median is 320 mg/L.
- Nearest city with clearly softer water: Zduńska Wola, 61 km away (195 mg/L).
- Nearest city with clearly harder water: Oleśnica, 78 km away (445 mg/L).
Ranking of the hardest and softest water in Poland →
What it means at home
- Severe scale: heater elements and washing-machine heaters fail early.
- Detergent use is very high; taps and screens coat within days.
- Dishwasher at maximum salt setting.
- An ion-exchange softener is practically essential; RO for drinking water.
How much salt will you use for softening?
Yes. At this hardness a softener pays for itself through appliance life and detergent.
Descale a coffee machine or kettle about every 1 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Kalisz
| Brand | Setting for this water |
|---|---|
| Bosch | H04 |
| Miele | 16 °dH |
| AEG / Electrolux | 4 |
| Beko | 4th |
| Hoover | S2 |
| LG | H3 |
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 Kalisz water hard or soft?
It is very hard: 280 mg/L as CaCO₃ (16.4 gpg, 15.7 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Kalisz safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Polish suppliers report total hardness in mg/L CaCO₃; the drinking-water regulation range is 60–500 mg/L.
How many grains per gallon is Kalisz water?
16.4 gpg, equal to 15.7 °dH, 28 °fH or 280 mg/L calcium carbonate.
What dishwasher salt setting should I use in Kalisz?
For 280 mg/L (15.7 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Kalisz?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: PWiK Kalisz, jakość wody I półrocze 2024 (2024). Method: figure published by the water supplier. PWiK Kalisz, jakość wody I półrocze 2024 · Outdated figure? Tell us