The municipalities with the hardest water in Luxembourg
Ranking of Luxembourg municipalities with the hardest tap water (°fH), updated automatically from the official AGE data.
Where is the water hardest in Luxembourg?
Water hardness varies greatly from one municipality to another depending on the geology the water passes through. Here is the live ranking of the municipalities with the hardest tap water, expressed in French degrees (°fH). The higher the value, the more calcareous the water — and the more relevant a softener.
Top 10 municipalities with the hardest water
| # | Municipality | Hardness |
|---|---|---|
| 1 | Bettendorf | 50.0 °fH |
| 2 | Schengen | 47.0 °fH |
| 3 | Mondorf-les-Bains | 45.3 °fH |
| 4 | Bech | 33.1 °fH |
| 5 | Weiler-la-Tour | 32.7 °fH |
| 6 | Colmar-Berg | 30.5 °fH |
| 7 | Consdorf | 30.1 °fH |
| 8 | Berdorf | 29.1 °fH |
| 9 | Vallée de l'Ernz | 28.9 °fH |
| 10 | Attert | 28.8 °fH |
Why these municipalities have the hardest water
Water picks up calcium and magnesium as it passes through calcareous rock. In Luxembourg, the Gutland (centre and south) and the Moselle valley sit on calcareous aquifers: the water there is markedly harder than in the Oesling (north), whose schist and sandstone terrain yields soft water.
Hard water: effects and solution
Above 25 °fH, limescale scales up pipes and water heaters (up to +30% consumption), stiffens laundry and dries out the skin. The reference solution is a softener, fitted at the water inlet, which removes limescale for the whole house. To find out who can install it at your home, see our installers page.
Limescale is not a drinkability issue (calcium is even good for health): it is a domestic matter — appliances, comfort, maintenance.
Your municipality is not in the top 10?
The ranking shows only the 10 hardest municipalities, but many others have moderately hard to hard water. Check your municipality profile for your exact hardness, or run the free diagnostic in two minutes.
Frequently asked questions
Which municipality has the hardest water in Luxembourg?
The ranking above, computed live from the official AGE data, shows in first place the municipality whose tap water has the highest hardness (°fH). It is updated automatically.
How is water hardness measured?
In French degrees (°fH): 1 °fH = 10 mg/L of calcium carbonate. Below 15 °fH water is soft, between 15 and 25 °fH moderately hard, above 25 °fH hard to very hard.
What should I do if my municipality's water is hard?
An ion-exchange softener, fitted at the water inlet, removes limescale and protects the whole house. Our partner installers operate in every Luxembourg municipality with a free quote.
Does the ranking change?
Yes. It is generated automatically from the latest official datasets, so it always reflects the most recent values published by the Water Management Administration.