Water hardness in Gossau (ZH)
31.2 °fH very hard
Tap water in Gossau (ZH) is very hard: 31.2 °fH (312 mg/L · 18.2 gpg · 17.5 °dH).
Source: Wasserversorgungs-Genossenschaft Grüt und Gossau (via SVGW trinkwasser.ch) (2024) · data checked 2026-10-21
In the canton of Zurich, drinking water comes partly from Lake Zurich and partly from groundwater and springs, and communities relying mostly on groundwater and springs tend to have harder water. Wasserversorgungs-Genossenschaft Grüt und Gossau reports a hardness of 312.0 mg/L CaCO₃. 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 | 31.2 °fH |
|---|---|
| Utility | Wasserversorgungs-Genossenschaft Grüt und Gossau |
How Gossau (ZH) compares
- Tap water in Gossau (ZH) is 17 % harder than the median of the 650 cities we track in Switzerland (26.7 °fH).
- By hardness it ranks 203 of 650 in Switzerland (1 = hardest); 69 % of these cities have softer water.
- In ZH it is number 40 of 116 cities; the regional median is 28.4 °fH.
- Nearest city with clearly softer water: Grüningen, 3 km away (22.9 °fH).
- Nearest city with clearly harder water: Elsau, 22 km away (40.1 °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 Gossau
| Brand | Setting for this water |
|---|---|
| Bosch | H05 |
| Miele | 17 °dH |
| AEG / Electrolux | 4 |
| Beko | 5th |
| Hoover | S3 |
| 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 Gossau (ZH) water hard or soft?
It is very hard: 312 mg/L as CaCO₃ (18.2 gpg, 17.5 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Gossau (ZH) 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 Gossau (ZH) water?
18.2 gpg, equal to 17.5 °dH, 31.2 °fH or 312 mg/L calcium carbonate.
What dishwasher salt setting should I use in Gossau (ZH)?
For 312 mg/L (17.5 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Gossau (ZH)?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: Wasserversorgungs-Genossenschaft Grüt und Gossau (via SVGW trinkwasser.ch) (2024). Method: figure published by the water supplier. Wasserversorgungs-Genossenschaft Grüt und Gossau (via SVGW trinkwasser.ch) · Outdated figure? Tell us