Water hardness in Millau
23.9 °fH very hard
Tap water in Millau is very hard: 23.9 °fH (239 mg/L · 14 gpg · 13.4 °dH).
Source: Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 12145 (2026-08) · data checked 2026-10-19
Range across supply zones: 20–252 mg/L.
Millau is served by several operators: the Creissels town hall, the SIAEP Causse Noir and Veolia Millau. The ARS health monitoring (SISE-Eaux, August 2026) gives a median of 239 mg/L CaCO₃ (23.9 °f), but measurements range from 20 to 252 mg/L. Check the value for your own address.
TH en °fH : douce < 15, moyennement dure 15–25, dure 25–35, très dure > 35 °fH (classes usuelles ARS).
Water data
| Total hardness | 23.9 °fH |
|---|---|
| Utility | Mairie De Creissels; Siaep Causse Noir; Veolia Millau |
How Millau compares
- Tap water in Millau is close to the median of the 33641 cities we track in France (23.9 °fH).
- By hardness it ranks 16769 of 33641 in France (1 = hardest); 50 % of these cities have softer water.
- In Aveyron it is number 52 of 285 cities; the regional median is 12.3 °fH.
- Nearest city with clearly softer water: La Cresse, 10 km away (14.1 °fH).
- Nearest city with clearly harder water: Comprégnac, 9 km away (30.8 °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 Millau
| Brand | Setting for this water |
|---|---|
| Bosch | H04 |
| Miele | 13 °dH |
| AEG / Electrolux | 3 |
| Beko | 4th |
| Hoover | S2 |
| LG | H2 |
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 Millau water hard or soft?
It is very hard: 239 mg/L as CaCO₃ (14 gpg, 13.4 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Millau 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 Millau water?
14 gpg, equal to 13.4 °dH, 23.9 °fH or 239 mg/L calcium carbonate.
What dishwasher salt setting should I use in Millau?
For 239 mg/L (13.4 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Millau?
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 12145 (2026-08). Method: own measurement. Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 12145 · Outdated figure? Tell us