Water hardness in Tübingen
12.6 °dH very hard
Tap water in Tübingen is very hard: 12.6 °dH (226 mg/L · 13.2 gpg · 22.6 °fH).
Source: Stadtwerke Tübingen - Trinkwasserbericht 2025 (2025) · data checked 2026-10-20
Range across supply zones: 162–246 mg/L.
4 supply zones — hardness varies by neighbourhood; the figure above is the median.
Hardness by district / supply zone
| °dH | mg/L | ||
|---|---|---|---|
| ASG Wasser (Bühl, Hirschau, Unterjesingen Niederzone) | 13.2 | 237 | very hard |
| BWV Wasser (Berghof, Eichhalde, Herrlesberg, Pfrondorf) | 9.1 | 162 | hard |
| Mischwasser ASG / BWV (Hagelloch, Unterjesingen Hochzone) | 12.1 | 215 | very hard |
| Mischwasser BWV / Eigenwasser (Kernstadt, Derendingen, Kilchberg, Kreßbach, Lustnau, Weilheim, Bebenhausen) | 13.8 | 246 | very hard |
Stadtwerke Tübingen's 2025 water report separates four supply zones, depending on how BWV water, ASG water and the utility's own water are mixed. The median is 225.8 mg/L CaCO₃ and the range is 162.4 to 246.3 mg/L. Unmixed BWV water is the softest, serving areas such as Pfrondorf. The report has no sampling date, only the year.
German law (WRMG) uses 3 bands: soft < 8.4 °dH, medium 8.4–14 °dH, hard > 14 °dH.
Water data
| Total hardness | 12.6 °dH |
|---|---|
| Utility | Stadtwerke Tübingen (swt) |
How Tübingen compares
- Tap water in Tübingen is 10 % harder than the median of the 809 cities we track in Germany (11.5 °dH).
- By hardness it ranks 354 of 809 in Germany (1 = hardest); 56 % of these cities have softer water.
- In Baden-Württemberg it is number 76 of 146 cities; the regional median is 12.8 °dH.
- Nearest city with clearly softer water: Eningen unter Achalm, 15 km away (9.1 °dH).
- Nearest city with clearly harder water: Hechingen, 20 km away (16.2 °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 Tübingen
| Brand | Setting for this water |
|---|---|
| Bosch | H04 |
| Miele | 13 °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 Tübingen water hard or soft?
It is very hard: 226 mg/L as CaCO₃ (13.2 gpg, 12.6 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Tübingen 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 Tübingen water?
13.2 gpg, equal to 12.6 °dH, 22.6 °fH or 226 mg/L calcium carbonate.
What dishwasher salt setting should I use in Tübingen?
For 226 mg/L (12.6 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Tübingen?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: Stadtwerke Tübingen - Trinkwasserbericht 2025 (2025). Method: figure published by the water supplier. Stadtwerke Tübingen - Trinkwasserbericht 2025 · Outdated figure? Tell us