Water hardness in Münster
13.8 °dH very hard
Tap water in Münster is very hard: 13.8 °dH (246 mg/L · 14.4 gpg · 24.6 °fH).
Source: Stadtwerke Münster – Jahresmittelwerte Trinkwasseranalysen 2025 (2025) · data checked 2026-10-23
Range across supply zones: 196–302 mg/L.
4 supply zones — hardness varies by neighbourhood; the figure above is the median.
Hardness by district / supply zone
| °dH | mg/L | ||
|---|---|---|---|
| Bezug Gelsenwasser AG | 11 | 196 | very hard |
| Hohe Ward | 12.5 | 223 | very hard |
| Hornheide (Aufbereitung ab 08/2026 senkt Härte in mittleren Bereich) | 15.1 | 270 | very hard |
| Vennheide | 16.9 | 302 | very hard |
Stadtwerke Münster publishes 2025 annual mean analyses for four supply areas. The city figure is 246.3 mg/L CaCO₃, within a range of 196.4 mg/L (supply bought from Gelsenwasser) to 301.7 mg/L (Vennheide). The utility notes that treatment at Hornheide (269.5 mg/L) will lower hardness to a medium range from August 2026, so that area may change. Check which area your street belongs to before sizing a softener.
German law (WRMG) uses 3 bands: soft < 8.4 °dH, medium 8.4–14 °dH, hard > 14 °dH.
Water data
| Total hardness | 13.8 °dH |
|---|---|
| ca_mg_l | 71.2 |
| mg_mg_l | 4.5 |
| mmol_l | 1.96 |
| Utility | Stadtwerke Münster |
How Münster compares
- Tap water in Münster is 20 % harder than the median of the 809 cities we track in Germany (11.5 °dH).
- By hardness it ranks 303 of 809 in Germany (1 = hardest); 62 % of these cities have softer water.
- In Nordrhein-Westfalen it is number 42 of 153 cities; the regional median is 11.3 °dH.
- Nearest city with clearly softer water: Nottuln, 19 km away (9.9 °dH).
- Nearest city with clearly harder water: Greven, 14 km away (20 °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 Münster
| 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 Münster water hard or soft?
It is very hard: 246 mg/L as CaCO₃ (14.4 gpg, 13.8 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Münster 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 Münster water?
14.4 gpg, equal to 13.8 °dH, 24.6 °fH or 246 mg/L calcium carbonate.
What dishwasher salt setting should I use in Münster?
For 246 mg/L (13.8 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Münster?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: Stadtwerke Münster – Jahresmittelwerte Trinkwasseranalysen 2025 (2025). Method: figure published by the water supplier. Stadtwerke Münster – Jahresmittelwerte Trinkwasseranalysen 2025 · Outdated figure? Tell us