Water hardness in Trostberg an der Alz
14.4 °dH very hard
Tap water in Trostberg an der Alz is very hard: 14.4 °dH (257 mg/L · 15 gpg · 25.7 °fH).
Source: Stadtwerke Trostberg, Prüfbericht Brunnen Hannslau 2026 (Probenahme 02.09.2026) (2026-09) · data checked 2026-11-03
The 14.4 °dH shown for Trostberg an der Alz comes from a single source: the Prüfbericht for the Brunnen Hannslau, sampled on 02.09.2026 by Stadtwerke Trostberg. It is one well sample, not a town-wide average, and the utility's other supply systems are not covered here. The report classes the water as hard. Hardness at your address may differ if another system supplies it, so ask the Stadtwerke which one applies.
German law (WRMG) uses 3 bands: soft < 8.4 °dH, medium 8.4–14 °dH, hard > 14 °dH.
Water data
| Total hardness | 14.4 °dH |
|---|---|
| Utility | Stadtwerke Trostberg Wasserversorgung GmbH |
How Trostberg an der Alz compares
- Tap water in Trostberg an der Alz is 25 % harder than the median of the 809 cities we track in Germany (11.5 °dH).
- By hardness it ranks 279 of 809 in Germany (1 = hardest); 65 % of these cities have softer water.
- In Bayern it is number 81 of 137 cities; the regional median is 15.8 °dH.
- Nearest city with clearly softer water: Altötting, 27 km away (7.7 °dH).
- Nearest city with clearly harder water: Bernau am Chiemsee, 17 km away (21.5 °dH).
Ranking of the hardest and softest water in Germany →
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 Trostberg an der Alz
| Brand | Setting for this water |
|---|---|
| Bosch | H04 |
| Miele | 14 °dH |
| AEG / Electrolux | 3 |
| 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 Trostberg an der Alz water hard or soft?
It is very hard: 257 mg/L as CaCO₃ (15 gpg, 14.4 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Trostberg an der Alz safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. German law (WRMG) uses 3 bands: soft < 8.4 °dH, medium 8.4–14 °dH, hard > 14 °dH.
How many grains per gallon is Trostberg an der Alz water?
15 gpg, equal to 14.4 °dH, 25.7 °fH or 257 mg/L calcium carbonate.
What dishwasher salt setting should I use in Trostberg an der Alz?
For 257 mg/L (14.4 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Trostberg an der Alz?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: Stadtwerke Trostberg, Prüfbericht Brunnen Hannslau 2026 (Probenahme 02.09.2026) (2026-09). Method: figure published by the water supplier. Stadtwerke Trostberg, Prüfbericht Brunnen Hannslau 2026 (Probenahme 02.09.2026) · Outdated figure? Tell us