Water hardness in Erlangen
11.9 °dH very hard
Tap water in Erlangen is very hard: 11.9 °dH (212 mg/L · 12.4 gpg · 21.2 °fH).
Source: ESTW - Härtebereiche im Versorgungsgebiet Erlangen (Stand 03.02.2026) (2026-02) · data checked 2026-10-20
Range across supply zones: 175–273 mg/L.
6 supply zones — hardness varies by neighbourhood; the figure above is the median.
Hardness by district / supply zone
| °dH | mg/L | ||
|---|---|---|---|
| Behälter am Burgberg | 9.8 | 175 | hard |
| Bezug N-Ergie (purchased water, southern part) | 15.3 | 273 | very hard |
| Bezug WFW (Wasserversorgung fränkischer Wirtschaftsraum, purchased water) | 14.1 | 252 | very hard |
| Hochbehälter am Meilwald | 10.8 | 193 | very hard |
| Wasserwerk Ost | 10.5 | 188 | very hard |
| Wasserwerk West 1 | 12.9 | 230 | very hard |
Erlanger Stadtwerke publishes a table of six supplies, dated 3 February 2026, in mmol/l only. The city's own works and reservoirs give the lower values. Water bought from N-Ergie and WFW is the hardest. The median is 211.7 mg/L CaCO₃ and the range is 175.2 to 273.2 mg/L, so the district you live in matters.
German law (WRMG) uses 3 bands: soft < 8.4 °dH, medium 8.4–14 °dH, hard > 14 °dH.
Water data
| Total hardness | 11.9 °dH |
|---|---|
| Utility | Erlanger Stadtwerke AG (ESTW) |
How Erlangen compares
- Tap water in Erlangen is close to the median of the 809 cities we track in Germany (11.5 °dH).
- By hardness it ranks 388 of 809 in Germany (1 = hardest); 52 % of these cities have softer water.
- In Bayern it is number 100 of 137 cities; the regional median is 15.8 °dH.
- Nearest city with clearly softer water: Heroldsberg, 10 km away (9.4 °dH).
- Nearest city with clearly harder water: Fürth, 13 km away (15 °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 Erlangen
| Brand | Setting for this water |
|---|---|
| Bosch | H03 |
| Miele | 12 °dH |
| AEG / Electrolux | 3 |
| Beko | 3rd |
| 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 Erlangen water hard or soft?
It is very hard: 212 mg/L as CaCO₃ (12.4 gpg, 11.9 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Erlangen 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 Erlangen water?
12.4 gpg, equal to 11.9 °dH, 21.2 °fH or 212 mg/L calcium carbonate.
What dishwasher salt setting should I use in Erlangen?
For 212 mg/L (11.9 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Erlangen?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: ESTW - Härtebereiche im Versorgungsgebiet Erlangen (Stand 03.02.2026) (2026-02). Method: figure published by the water supplier. ESTW - Härtebereiche im Versorgungsgebiet Erlangen (Stand 03.02.2026) · Outdated figure? Tell us