Water hardness in Dison
7.9 °fH moderately hard
Tap water in Dison is moderately hard: 7.9 °fH (79 mg/L · 4.6 gpg · 4.4 °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: 79–80 mg/L.
Dison, in Liège province, is supplied by SWDE. The SPW gives 79.2 mg/L CaCO₃ for 2025, between 78.5 and 80.0 mg/L. The water is moderately hard, noticeably softer than in many Walloon municipalities.
Belgian suppliers report hardness in °f (French degrees); 1 °f = 10 mg/L CaCO₃.
Water data
| Total hardness | 7.9 °fH |
|---|---|
| Utility | SWDE |
How Dison compares
- Tap water in Dison is 75 % softer than the median of the 1091 cities we track in Belgium (31.6 °fH).
- By hardness it ranks 1001 of 1091 in Belgium (1 = hardest); 8 % of these cities have softer water.
- In Liège it is number 176 of 237 cities; the regional median is 27.3 °fH.
- Nearest city with clearly softer water: La Reid, 14 km away (4.7 °fH).
- Nearest city with clearly harder water: Wegnez, 4 km away (11.1 °fH).
Ranking of the hardest and softest water in Belgium →
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 Dison
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 4 °dH |
| AEG / Electrolux | 2 |
| Beko | 1st |
| 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 Dison water hard or soft?
It is moderately hard: 79 mg/L as CaCO₃ (4.6 gpg, 4.4 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Dison 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 Dison water?
4.6 gpg, equal to 4.4 °dH, 7.9 °fH or 79 mg/L calcium carbonate.
What dishwasher salt setting should I use in Dison?
For 79 mg/L (4.4 °dH) check your manufacturer's table: level 2–3.
Do I need a water softener in Dison?
Not essential; a scale inhibitor protects the heater cheaply.
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