Water hardness in Arluno
30.7 °fH very hard
Tap water in Arluno is very hard: 30.7 °fH (307 mg/L · 17.9 gpg · 17.2 °dH).
Source: Gruppo CAP, analisi acquedotto (open data), 2025 Q3–2026 Q2 (2026-06) · data checked 2026-10-19
Range across supply zones: 232–331 mg/L.
Gruppo CAP, the utility for the Milan metropolitan area, publishes open analysis data for Arluno. Hardness is calculated from calcium and magnesium at 307.1 mg/L CaCO₃, with samples from the third quarter of 2025 to the second quarter of 2026 between 232.0 and 331.1 mg/L. That is very hard water, among the harder values we hold for the area. We have not verified which wells supply the town. Expect fast scale in kettles, boilers and dishwashers, and consider a softener.
Italian utilities report °f (French degrees); D.Lgs. 31/2001 recommends 15–50 °f.
Water data
| Total hardness | 30.7 °fH |
|---|
How Arluno compares
- Tap water in Arluno is 45 % harder than the median of the 629 cities we track in Italy (21.2 °fH).
- By hardness it ranks 88 of 629 in Italy (1 = hardest); 86 % of these cities have softer water.
- In Lombardia it is number 19 of 142 cities; the regional median is 24.9 °fH.
- Nearest city with clearly softer water: Vittuone, 2 km away (22.3 °fH).
- Nearest city with clearly harder water: Locate di Triulzi, 27 km away (40.3 °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 Arluno
| Brand | Setting for this water |
|---|---|
| Bosch | H05 |
| Miele | 17 °dH |
| AEG / Electrolux | 4 |
| Beko | 5th |
| Hoover | S3 |
| 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 Arluno water hard or soft?
It is very hard: 307 mg/L as CaCO₃ (17.9 gpg, 17.2 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Arluno 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 Arluno water?
17.9 gpg, equal to 17.2 °dH, 30.7 °fH or 307 mg/L calcium carbonate.
What dishwasher salt setting should I use in Arluno?
For 307 mg/L (17.2 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Arluno?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: Gruppo CAP, analisi acquedotto (open data), 2025 Q3–2026 Q2 (2026-06). Method: computed from supplier's calcium and magnesium. Gruppo CAP, analisi acquedotto (open data), 2025 Q3–2026 Q2 · Outdated figure? Tell us