Water hardness in Zirndorf
19 °dH very hard
Tap water in Zirndorf is very hard: 19 °dH (338 mg/L · 19.8 gpg · 33.8 °fH).
Source: Stadtwerke Zirndorf GmbH - Wasseranalyse (Prüfbericht 15.07.2025) (2025-07) · data checked 2026-10-24
Range across supply zones: 295–382 mg/L.
2 supply zones — hardness varies by neighbourhood; the figure above is the median.
Hardness by district / supply zone
| °dH | mg/L | ||
|---|---|---|---|
| Alte Veste (Hochbehälter Alte Veste) | 16.5 | 295 | very hard |
| Weitersdorf (Hochbehälter Turm Weitersdorf) | 21.4 | 382 | very hard |
Stadtwerke Zirndorf published a test report dated 15 July 2025 covering two supply zones. The Alte Veste reservoir zone is at 294.5 mg/L CaCO₃ and the Weitersdorf zone at 382.0 mg/L, which gives a town figure of 338.3 mg/L, all in the very hard class. Fürth, 3 km away, is listed at 266.9 mg/L, so the value can change quickly across the Nuremberg area. Descaling and a water-hardness setting on your dishwasher are the practical first steps.
German law (WRMG) uses 3 bands: soft < 8.4 °dH, medium 8.4–14 °dH, hard > 14 °dH.
Water data
| Total hardness | 19 °dH |
|---|---|
| Utility | Stadtwerke Zirndorf GmbH |
How Zirndorf compares
- Tap water in Zirndorf is 65 % harder than the median of the 809 cities we track in Germany (11.5 °dH).
- By hardness it ranks 110 of 809 in Germany (1 = hardest); 86 % of these cities have softer water.
- In Bayern it is number 36 of 137 cities; the regional median is 15.8 °dH.
- Nearest city with clearly softer water: Fürth, 3 km away (15 °dH).
- Nearest city with clearly harder water: Schlüsselfeld, 41 km away (25.6 °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 Zirndorf
| Brand | Setting for this water |
|---|---|
| Bosch | H05 |
| Miele | 19 °dH |
| AEG / Electrolux | 5 |
| 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 Zirndorf water hard or soft?
It is very hard: 338 mg/L as CaCO₃ (19.8 gpg, 19 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Zirndorf 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 Zirndorf water?
19.8 gpg, equal to 19 °dH, 33.8 °fH or 338 mg/L calcium carbonate.
What dishwasher salt setting should I use in Zirndorf?
For 338 mg/L (19 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Zirndorf?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: Stadtwerke Zirndorf GmbH - Wasseranalyse (Prüfbericht 15.07.2025) (2025-07). Method: figure published by the water supplier. Stadtwerke Zirndorf GmbH - Wasseranalyse (Prüfbericht 15.07.2025) · Outdated figure? Tell us