Water hardness in Hollogne-aux-Pierres
37.3 °fH very hard
Tap water in Hollogne-aux-Pierres is very hard: 37.3 °fH (373 mg/L · 21.8 gpg · 20.9 °dH).
Source: SPW, qualité de l'eau potable par zone de distribution, année civile 2025 (2025) · data checked 2026-10-19
Range across supply zones: 342–424 mg/L.
CILE draws on limestone springs at Néblon in the Condroz and on the chalk aquifer of Hesbaye north-west of Liège, and buys in the rest of its water; both are calcium-rich rocks. The 2025 figure is 373.0 mg/L CaCO₃, within a reported range of 342.2 to 423.9 mg/L, so the exact value depends on your street. This is very hard water: expect heavy limescale on taps, glass and heating elements, and higher detergent and descaling needs.
Belgian suppliers report hardness in °f (French degrees); 1 °f = 10 mg/L CaCO₃.
Water data
| Total hardness | 37.3 °fH |
|---|---|
| Utility | CILE |
How Hollogne-aux-Pierres compares
- Tap water in Hollogne-aux-Pierres is 18 % harder than the median of the 1091 cities we track in Belgium (31.6 °fH).
- By hardness it ranks 300 of 1091 in Belgium (1 = hardest); 72 % of these cities have softer water.
- In Liège it is number 65 of 237 cities; the regional median is 27.3 °fH.
- Nearest city with clearly softer water: Flémalle-Haute, 5 km away (20.8 °fH).
- Nearest city with clearly harder water: Oisquercq, 88 km away (48.9 °fH).
Ranking of the hardest and softest water in Belgium →
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 Hollogne-aux-Pierres
| Brand | Setting for this water |
|---|---|
| Bosch | H05 |
| Miele | 21 °dH |
| AEG / Electrolux | 5 |
| Beko | 6th |
| Hoover | S3 |
| LG | H4 |
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 Hollogne-aux-Pierres water hard or soft?
It is very hard: 373 mg/L as CaCO₃ (21.8 gpg, 20.9 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Hollogne-aux-Pierres safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Belgian suppliers report hardness in °f (French degrees); 1 °f = 10 mg/L CaCO₃.
How many grains per gallon is Hollogne-aux-Pierres water?
21.8 gpg, equal to 20.9 °dH, 37.3 °fH or 373 mg/L calcium carbonate.
What dishwasher salt setting should I use in Hollogne-aux-Pierres?
For 373 mg/L (20.9 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Hollogne-aux-Pierres?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: SPW, qualité de l'eau potable par zone de distribution, année civile 2025 (2025). Method: figure published by the water supplier. SPW, qualité de l'eau potable par zone de distribution, année civile 2025 · Outdated figure? Tell us