Water hardness in Frastanz
15.4 °dH very hard
Tap water in Frastanz is very hard: 15.4 °dH (275 mg/L · 16.1 gpg · 27.5 °fH).
Source: Marktgemeinde Frastanz, Trinkwasseranalysen, Prüfbericht Pumpwerk Frastanz (Umweltinstitut, 12.12.2025) (2025-10) · data checked 2026-11-05
Range across supply zones: 271–279 mg/L.
2 supply zones — hardness varies by neighbourhood; the figure above is the median.
Hardness by district / supply zone
| °dH | mg/L | ||
|---|---|---|---|
| Pumpwerk Frastanz | 15.6 | 279 | very hard |
| Untere Frastafedner | 15.2 | 271 | very hard |
Frastanz has published a test report for its Pumpwerk (pumping station). From the analysed values we compute a total hardness of 274.9 mg/L CaCO₃ (about 15.4 °dH), with two results between 271.3 and 278.5 mg/L. The figure is computed rather than measured directly and sits in the very hard category, so descaling coffee machines and boilers will be a regular task.
Angabe in °dH; Härtebereiche wie in Deutschland üblich.
Water data
| Total hardness | 15.4 °dH |
|---|---|
| Utility | Marktgemeinde Frastanz (Wasserversorgung) |
How Frastanz compares
- Tap water in Frastanz is 10 % harder than the median of the 159 cities we track in Austria (14 °dH).
- By hardness it ranks 43 of 159 in Austria (1 = hardest); 73 % of these cities have softer water.
- In Vorarlberg it is number 2 of 7 cities; the regional median is 13.4 °dH.
- Nearest city with clearly softer water: Rankweil, 6 km away (8 °dH).
Ranking of the hardest and softest water in Austria →
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 Frastanz
| Brand | Setting for this water |
|---|---|
| Bosch | H04 |
| Miele | 15 °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 Frastanz water hard or soft?
It is very hard: 275 mg/L as CaCO₃ (16.1 gpg, 15.4 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Frastanz safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Angabe in °dH; Härtebereiche wie in Deutschland üblich.
How many grains per gallon is Frastanz water?
16.1 gpg, equal to 15.4 °dH, 27.5 °fH or 275 mg/L calcium carbonate.
What dishwasher salt setting should I use in Frastanz?
For 275 mg/L (15.4 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Frastanz?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: Marktgemeinde Frastanz, Trinkwasseranalysen, Prüfbericht Pumpwerk Frastanz (Umweltinstitut, 12.12.2025) (2025-10). Method: computed from supplier's calcium and magnesium. Marktgemeinde Frastanz, Trinkwasseranalysen, Prüfbericht Pumpwerk Frastanz (Umweltinstitut, 12.12.2025) · Outdated figure? Tell us