Map of water hardness in Luxembourg
Every municipality in Luxembourg ranked by water hardness. Official AGE data.
How to read the hardness map
Our interactive map combines the official data of the Water Management Administration with a five-level classification: very soft (blue), soft (green), moderately hard (yellow), hard (orange), very hard (red). You can click on any municipality to access its detailed profile.
Hardness can vary from street to street within the same municipality, as several sources may feed the network. The map gives the reference value; always check your water bill or ask your water utility for the analysis.
The geography of hardness in Luxembourg
The Oesling (north) and some municipalities in the north-east, on schist and sandstone terrain, deliver the softest water in the country. The Gutland (centre and south) as well as the Moselle benefit from calcareous aquifers: the water there is harder. The mining south, around Esch and Differdange, is in the upper-middle range.
| Region | Dominant geology | Typical hardness | Level |
|---|---|---|---|
| Oesling (north) | Schist, sandstone | 5–12°fH | Soft |
| North-east | Sandstone | 8–15°fH | Soft to medium |
| Gutland (centre) | Limestone | 20–35°fH | Hard |
| Moselle (east) | Limestone | 25–40°fH | Hard to very hard |
| Mining south | Mixed | 18–30°fH | Medium to hard |
Top 10 hardest municipalities
The municipalities with the highest values (> 25°fH) combine risks for household equipment with domestic discomfort. For their residents, installing a water softener typically pays for itself in 4 to 6 years. See our detailed list and the dedicated page for each municipality.
The softest municipalities
Some municipalities in the north enjoy naturally very soft water (< 7°fH). For these residents there is no need for a water softener: any priority shifts towards filtering drinking water (a reverse-osmosis unit) to treat possible chemical residues.
Frequently asked questions
Where does the map data come from?
It is based on the values published by the Water Management Administration (AGE) and the water utilities. We classify them into 5 hardness levels for easier reading.
At what hardness do you need a water softener?
Above 25°fH (hard water), scaling becomes significant and a softener is generally recommended. Above 35°fH it becomes almost essential to protect your equipment.
Why is the water harder in the south than in the north?
The north (Oesling) sits on schist and sandstone terrain low in limestone, while the centre and east cross calcareous aquifers that load the water with calcium and magnesium.
How do I find the exact hardness for my address?
Click on your municipality on the map for the reference value, then check your water bill or ask your water utility for the precise analysis, as it can vary depending on the source.
Is hard water dangerous to health?
No, hard water is not dangerous to drink; calcium and magnesium are even beneficial. The problem is purely domestic: scaling of equipment and discomfort.