Water hardness in Thun
23 °fH very hard
Tap water in Thun is very hard: 23 °fH (230 mg/L · 13.4 gpg · 12.9 °dH).
Source: Energie Thun AG - Wasser (Wasserhärten nach Standort) (2026) · data checked 2026-10-23
Range across supply zones: 210–250 mg/L.
In the canton of Bern, drinking water comes mostly from groundwater and springs, supplemented by lake water in the lake regions. Energie Thun AG reports a hardness of 230.0 mg/L CaCO₃, with values from 210.0 to 250.0 mg/L depending on the address. Scale forms quickly on heating elements and fittings, so a softener or strict descaling routine is worth considering.
In der Schweiz wird meist in °fH angegeben (1 °fH = 0,56 °dH).
Water data
| Total hardness | 23 °fH |
|---|---|
| Utility | Energie Thun AG |
How Thun compares
- Tap water in Thun is 14 % softer than the median of the 650 cities we track in Switzerland (26.7 °fH).
- By hardness it ranks 430 of 650 in Switzerland (1 = hardest); 33 % of these cities have softer water.
- In BE it is number 41 of 83 cities; the regional median is 23 °fH.
- Nearest city with clearly softer water: Amsoldingen, 5 km away (17.5 °fH).
- Nearest city with clearly harder water: Hilterfingen, 4 km away (30.6 °fH).
Ranking of the hardest and softest water in Switzerland →
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 Thun
| Brand | Setting for this water |
|---|---|
| Bosch | H04 |
| Miele | 13 °dH |
| AEG / Electrolux | 3 |
| Beko | 4th |
| Hoover | S2 |
| 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 Thun water hard or soft?
It is very hard: 230 mg/L as CaCO₃ (13.4 gpg, 12.9 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Thun safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. In der Schweiz wird meist in °fH angegeben (1 °fH = 0,56 °dH).
How many grains per gallon is Thun water?
13.4 gpg, equal to 12.9 °dH, 23 °fH or 230 mg/L calcium carbonate.
What dishwasher salt setting should I use in Thun?
For 230 mg/L (12.9 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Thun?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: Energie Thun AG - Wasser (Wasserhärten nach Standort) (2026). Method: computed from supplier's calcium and magnesium. Energie Thun AG - Wasser (Wasserhärten nach Standort) · Outdated figure? Tell us