Water hardness in Cagliari
10.8 °fH moderately hard
Tap water in Cagliari is moderately hard: 10.8 °fH (108 mg/L · 6.3 gpg · 6 °dH).
Source: Abbanoa, qualità dell'acqua, semestri 2-2025…1-2026 (2026-05) · data checked 2026-10-20
Range across supply zones: 83–119 mg/L.
Abbanoa treats reservoir water for Cagliari; Sardinia has few natural sources suited to drinking water, so reservoirs carry most of the load; hardness follows the rocks of each reservoir's basin. Calculated from the utility's readings, hardness is 107.7 mg/L CaCO₃, with readings from 82.9 to 118.5 mg/L, which counts as moderately hard water. Most households need nothing beyond occasional descaling of the kettle and shower head.
Italian utilities report °f (French degrees); D.Lgs. 31/2001 recommends 15–50 °f.
Water data
| Total hardness | 10.8 °fH |
|---|
How Cagliari compares
- Tap water in Cagliari is 49 % softer than the median of the 629 cities we track in Italy (21.2 °fH).
- By hardness it ranks 514 of 629 in Italy (1 = hardest); 18 % of these cities have softer water.
- In Sardegna it is number 6 of 17 cities; the regional median is 9.9 °fH.
- Nearest city with clearly softer water: Nuoro, 122 km away (3.2 °fH).
- Nearest city with clearly harder water: Iglesias, 51 km away (32.7 °fH).
Ranking of the hardest and softest water in Italy →
What it means at home
- Visible kettle scale every few weeks; vinegar or citric acid is enough.
- Water heater and washing machine: some long-term scale; a scale inhibitor slows it.
- Dishwasher: medium salt setting.
- Softener optional; pays off mainly with a gas boiler or tankless heater.
How much salt will you use for softening?
Optional. A scale inhibitor or a small softener protects the heater; soap savings are modest.
Descale a coffee machine or kettle about every 3 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Cagliari
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 6 °dH |
| AEG / Electrolux | 2 |
| Beko | 2nd |
| Hoover | S1 |
| LG | H1 |
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 Cagliari water hard or soft?
It is moderately hard: 108 mg/L as CaCO₃ (6.3 gpg, 6 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Cagliari 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 Cagliari water?
6.3 gpg, equal to 6 °dH, 10.8 °fH or 108 mg/L calcium carbonate.
What dishwasher salt setting should I use in Cagliari?
For 108 mg/L (6 °dH) check your manufacturer's table: level 2–3.
Do I need a water softener in Cagliari?
Not essential; a scale inhibitor protects the heater cheaply.
Source
Source: Abbanoa, qualità dell'acqua, semestri 2-2025…1-2026 (2026-05). Method: computed from supplier's calcium and magnesium. Abbanoa, qualità dell'acqua, semestri 2-2025…1-2026 · Outdated figure? Tell us