Water Hardness Map in France
Water hardness varies significantly across French departments. Hard water (rich in limescale) causes pipe scaling, reduces appliance efficiency, and increases energy consumption. Use our interactive tool to check the average water hardness in your department and get personalised recommendations.
In France, over 60% of households receive water classified as hard or very hard (above 25 °f). The most affected regions are the Paris Basin, Nord-Pas-de-Calais, Provence, and Eastern France. The LIMPEO electromagnetic water descaler, manufactured by JAEGER SAS, effectively treats hard water without salt, chemicals, or maintenance.
Interactive Water Hardness Map
Click a department to see details
10
Soft water
< 15 °f
22
Medium water
15–25 °f
60
Hard water
25–35 °f
2
Very hard water
> 35 °f
Search your department
Type the name or number of your department to check the average water hardness in your area.
94 departments
Ain
Hard water
Aisne
Hard water
Allier
Medium water
Alpes-de-Haute-Provence
Hard water
Hautes-Alpes
Medium water
Alpes-Maritimes
Hard water
Ardèche
Medium water
Ardennes
Hard water
Ariège
Medium water
Aube
Hard water
Aude
Hard water
Aveyron
Medium water
Bouches-du-Rhône
Hard water
Calvados
Hard water
Cantal
Soft water
Charente
Hard water
Charente-Maritime
Hard water
Cher
Hard water
Corrèze
Soft water
Côte-d'Or
Hard water
Côtes-d'Armor
Soft water
Creuse
Soft water
Dordogne
Hard water
Doubs
Hard water
Drôme
Hard water
Eure
Hard water
Eure-et-Loir
Hard water
Finistère
Soft water
Gard
Hard water
Haute-Garonne
Hard water
Gers
Hard water
Gironde
Hard water
Hérault
Very hard water
Ille-et-Vilaine
Medium water
Indre
Hard water
Indre-et-Loire
Medium water
Isère
Hard water
Jura
Hard water
Landes
Medium water
Loir-et-Cher
Hard water
Loire
Medium water
Haute-Loire
Soft water
Loire-Atlantique
Medium water
Loiret
Hard water
Lot
Hard water
Lot-et-Garonne
Hard water
Lozère
Soft water
Maine-et-Loire
Medium water
Manche
Medium water
Marne
Hard water
Haute-Marne
Hard water
Mayenne
Medium water
Meurthe-et-Moselle
Hard water
Meuse
Hard water
Morbihan
Soft water
Moselle
Hard water
Nièvre
Medium water
Nord
Hard water
Oise
Hard water
Orne
Medium water
Pas-de-Calais
Very hard water
Puy-de-Dôme
Soft water
Pyrénées-Atlantiques
Medium water
Hautes-Pyrénées
Medium water
Pyrénées-Orientales
Hard water
Bas-Rhin
Hard water
Haut-Rhin
Hard water
Rhône
Hard water
Haute-Saône
Hard water
Saône-et-Loire
Hard water
Sarthe
Medium water
Savoie
Medium water
Haute-Savoie
Hard water
Paris
Hard water
Seine-Maritime
Hard water
Seine-et-Marne
Hard water
Yvelines
Hard water
Deux-Sèvres
Hard water
Somme
Hard water
Tarn
Medium water
Tarn-et-Garonne
Hard water
Var
Hard water
Vaucluse
Hard water
Vendée
Medium water
Vienne
Hard water
Haute-Vienne
Soft water
Vosges
Medium water
Yonne
Hard water
Territoire de Belfort
Hard water
Essonne
Hard water
Hauts-de-Seine
Hard water
Seine-Saint-Denis
Hard water
Val-de-Marne
Hard water
Val-d'Oise
Hard water
Recommendations based on your water hardness
Water hardness is measured in French degrees (°f). 1 °f equals 10 mg of calcium carbonate per litre. Here are our recommendations based on your water hardness level:
Soft water (< 15 °f)
Your water is naturally soft. An anti-limescale device is not essential, but the LIMPEO can improve taste and provide preventive protection for your plumbing.
Medium water (15–25 °f)
Your water is starting to deposit limescale. A LIMPEO J-250 device is recommended to protect your pipes and household appliances.
Hard water (25–35 °f)
Limescale builds up rapidly in your plumbing. A LIMPEO J-250 or J-320 device is strongly recommended to reduce scaling and save up to 25% on your energy bills.
Very hard water (> 35 °f)
Your water is very hard: high risk of deposits, appliance breakdowns, and excessive energy consumption. A LIMPEO J-320 or J-630 is essential to protect your installation.
What is water hardness?
Water hardness, also called hydrometric title (TH), measures the concentration of dissolved calcium (Ca²⁺) and magnesium (Mg²⁺) ions in water. It is expressed in French degrees (°f): 1 °f corresponds to 10 mg/L of CaCO₃. Water below 15 °f is considered soft, between 15 and 25 °f as moderately hard, between 25 and 35 °f as hard, and above 35 °f as very hard. Hardness mainly depends on local geology: limestone soils (Paris Basin, Jura, Provence) produce hard water, while granitic soils (Massif Central, Brittany, Vosges) yield soft water.
Impact of limescale on your home
Hard water causes limescale accumulation in pipes, water heaters, washing machines, and dishwashers. According to ADEME, 1 mm of limescale on a heating element increases energy consumption by 8 to 16%. Over 10 years, water at 30 °f can deposit up to 50 kg of limescale in your hot water system. The consequences include: reduced flow, boiler breakdowns, premature appliance replacement, dry skin, and dull hair after showering. The total annual cost of limescale for a French household is estimated between €300 and €800.
How LIMPEO treats limescale without chemicals
The LIMPEO electromagnetic descaler generates a pulsed magnetic field that modifies calcium carbonate crystallisation: instead of forming calcite (hard, adhesive crystals), calcium transforms into aragonite (fine, non-adhesive crystals). The result: limescale no longer deposits on surfaces and existing deposits gradually dissolve. This technology, validated by independent studies, requires no salt, no chemicals, and no maintenance. LIMPEO is manufactured in France by JAEGER SAS and backed by a 10-year warranty.
Frequently asked questions about water hardness
Protect your home from limescale
Discover the LIMPEO range: electromagnetic descaler with no salt, no chemicals, no maintenance. Made in France, 10-year warranty.