Water hardness in Greven
20 °dH very hard
Tap water in Greven is very hard: 20 °dH (357 mg/L · 20.9 gpg · 35.7 °fH).
Source: Stadtwerke Greven – Wasserhärte (2026) · data checked 2026-10-23
Stadtwerke Greven states a hardness of 357.0 mg/L CaCO₃ on its water hardness page, without a breakdown by zone. This is higher than Münster (246.3 mg/L) 14 km away and Altenberge (201.7 mg/L) 11 km away. The utility also quotes a value in mmol/L that does not match this figure exactly, so treat it as approximate.
German law (WRMG) uses 3 bands: soft < 8.4 °dH, medium 8.4–14 °dH, hard > 14 °dH.
Water data
| Total hardness | 20 °dH |
|---|---|
| mmol_l | 3.2 |
| Utility | Stadtwerke Greven |
How Greven compares
- Tap water in Greven is 74 % harder than the median of the 809 cities we track in Germany (11.5 °dH).
- By hardness it ranks 67 of 809 in Germany (1 = hardest); 91 % of these cities have softer water.
- In Nordrhein-Westfalen it is number 10 of 153 cities; the regional median is 11.3 °dH.
- Nearest city with clearly softer water: Altenberge, 11 km away (11.3 °dH).
- Nearest city with clearly harder water: Leopoldshöhe, 77 km away (25.2 °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 Greven
| Brand | Setting for this water |
|---|---|
| Bosch | H05 |
| Miele | 20 °dH |
| AEG / Electrolux | 5 |
| Beko | 6th |
| 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 Greven water hard or soft?
It is very hard: 357 mg/L as CaCO₃ (20.9 gpg, 20 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Greven 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 Greven water?
20.9 gpg, equal to 20 °dH, 35.7 °fH or 357 mg/L calcium carbonate.
What dishwasher salt setting should I use in Greven?
For 357 mg/L (20 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Greven?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: Stadtwerke Greven – Wasserhärte (2026). Method: figure published by the water supplier. Stadtwerke Greven – Wasserhärte · Outdated figure? Tell us