Water hardness in Aosta
21.2 °fH very hard
Tap water in Aosta is very hard: 21.2 °fH (212 mg/L · 12.4 gpg · 11.9 °dH).
Source: Comune di Aosta - Qualità dell acqua nei punti di approvvigionamento 2013-2020 (2020) · data checked 2026-10-29
Range across supply zones: 190–313 mg/L.
6 supply zones — hardness varies by neighbourhood; the figure above is the median.
Hardness by district / supply zone
| °fH | mg/L | ||
|---|---|---|---|
| Pozzo Birreria | 31.3 | 313 | very hard |
| Pozzo Cogne n°19 | 26 | 260 | very hard |
| Pozzo Giardini | 22 | 220 | very hard |
| Pozzo Montfleury | 19 | 190 | very hard |
| Pozzo Prato Fiera | 20.4 | 204 | very hard |
| Pozzo Solarolo | 20 | 200 | very hard |
This figure is over 3 years old; hardness may have changed.
The Comune di Aosta's report on its supply points for 2013 to 2020 gives a median hardness of 212 mg/L CaCO₃ (21.2 °f), with a range of 190 to 313 mg/L (19 to 31.3 °f). The water is very hard by our scale. The data are several years old and cover the municipal waterworks, so current values may differ.
Italian utilities report °f (French degrees); D.Lgs. 31/2001 recommends 15–50 °f.
Water data
| Total hardness | 21.2 °fH |
|---|---|
| Utility | Comune di Aosta (acquedotto comunale) |
How Aosta compares
- Tap water in Aosta is close to the median of the 629 cities we track in Italy (21.2 °fH).
- By hardness it ranks 317 of 629 in Italy (1 = hardest); 50 % of these cities have softer water.
- Nearest city with clearly softer water: Valprato Soana, 30 km away (7 °fH).
- Nearest city with clearly harder water: Montalto Dora, 51 km away (31 °fH).
Ranking of the hardest and softest water in Italy →
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 Aosta
| Brand | Setting for this water |
|---|---|
| Bosch | H03 |
| Miele | 12 °dH |
| AEG / Electrolux | 3 |
| Beko | 3rd |
| 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 Aosta water hard or soft?
It is very hard: 212 mg/L as CaCO₃ (12.4 gpg, 11.9 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Aosta safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Italian utilities report °f (French degrees); D.Lgs. 31/2001 recommends 15–50 °f.
How many grains per gallon is Aosta water?
12.4 gpg, equal to 11.9 °dH, 21.2 °fH or 212 mg/L calcium carbonate.
What dishwasher salt setting should I use in Aosta?
For 212 mg/L (11.9 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Aosta?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: Comune di Aosta - Qualità dell acqua nei punti di approvvigionamento 2013-2020 (2020). Method: figure published by the water supplier. Comune di Aosta - Qualità dell acqua nei punti di approvvigionamento 2013-2020 · Outdated figure? Tell us