Water hardness in Rumilly (Haute-Savoie)
25.6 °fH very hard
Tap water in Rumilly (Haute-Savoie) is very hard: 25.6 °fH (256 mg/L · 15 gpg · 14.3 °dH).
Source: Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 74225 (2026-06) · data checked 2026-10-19
Range across supply zones: 217–296 mg/L.
Rumilly in Haute-Savoie is served by Saur (Aix-les-Bains sector). The Alpine foothills are limestone and molasse, and the water is very hard: 256 mg/L CaCO₃, ranging from 217 to 296 mg/L. Hardness varies with the source.
TH en °fH : douce < 15, moyennement dure 15–25, dure 25–35, très dure > 35 °fH (classes usuelles ARS).
Water data
| Total hardness | 25.6 °fH |
|---|---|
| Utility | Saur Secteur Aix Les Bains |
How Rumilly (Haute-Savoie) compares
- Tap water in Rumilly (Haute-Savoie) is 7 % harder than the median of the 33641 cities we track in France (23.9 °fH).
- By hardness it ranks 14680 of 33641 in France (1 = hardest); 56 % of these cities have softer water.
- In Haute-Savoie it is number 109 of 273 cities; the regional median is 24.4 °fH.
- Nearest city with clearly softer water: Saint-Sylvestre, 7 km away (19.6 °fH).
- Nearest city with clearly harder water: Sales, 2 km away (36.6 °fH).
Ranking of the hardest and softest water in France →
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 Rumilly
| 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 Rumilly (Haute-Savoie) water hard or soft?
It is very hard: 256 mg/L as CaCO₃ (15 gpg, 14.3 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Rumilly (Haute-Savoie) safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. TH en °fH : douce < 15, moyennement dure 15–25, dure 25–35, très dure > 35 °fH (classes usuelles ARS).
How many grains per gallon is Rumilly (Haute-Savoie) water?
15 gpg, equal to 14.3 °dH, 25.6 °fH or 256 mg/L calcium carbonate.
What dishwasher salt setting should I use in Rumilly (Haute-Savoie)?
For 256 mg/L (14.3 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Rumilly (Haute-Savoie)?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 74225 (2026-06). Method: own measurement. Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 74225 · Outdated figure? Tell us