Water hardness in Theux
16.6 °fH hard
Tap water in Theux is hard: 16.6 °fH (166 mg/L · 9.7 gpg · 9.3 °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: 74–220 mg/L.
Theux, in the province of Liège, runs its own municipal supply. The SPW 2025 median is 166.0 mg/L CaCO₃, with a wide range from 74.0 to 220.0, so the water is hard on average but differs a lot between parts of the network. Ask the commune which zone you are in.
Belgian suppliers report hardness in °f (French degrees); 1 °f = 10 mg/L CaCO₃.
Water data
| Total hardness | 16.6 °fH |
|---|---|
| Utility | THEUX |
How Theux compares
- Tap water in Theux is 47 % softer than the median of the 1091 cities we track in Belgium (31.6 °fH).
- By hardness it ranks 884 of 1091 in Belgium (1 = hardest); 19 % of these cities have softer water.
- In Liège it is number 146 of 237 cities; the regional median is 27.3 °fH.
- Nearest city with clearly softer water: La Reid, 5 km away (4.7 °fH).
- Nearest city with clearly harder water: Louveigné, 7 km away (34.5 °fH).
Ranking of the hardest and softest water in Belgium →
What it means at home
- Fast scale on taps, shower screens and kettle; white spots on glassware.
- Water heater: efficiency loss and element failures within years if unprotected.
- Dry skin and dull hair after showering are common.
- Softener recommended; jug or reverse osmosis for drinking.
How much salt will you use for softening?
Recommended, especially with a heater or boiler: scale cuts efficiency and shortens its life.
Descale a coffee machine or kettle about every 2 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Theux
| Brand | Setting for this water |
|---|---|
| Bosch | H02 |
| Miele | 9 °dH |
| AEG / Electrolux | 2 |
| Beko | 3rd |
| Hoover | S1 |
| 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 Theux water hard or soft?
It is hard: 166 mg/L as CaCO₃ (9.7 gpg, 9.3 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Theux 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 Theux water?
9.7 gpg, equal to 9.3 °dH, 16.6 °fH or 166 mg/L calcium carbonate.
What dishwasher salt setting should I use in Theux?
For 166 mg/L (9.3 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Theux?
Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.
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