Water hardness in Mont-sur-Marchienne
32.5 °fH very hard
Tap water in Mont-sur-Marchienne is very hard: 32.5 °fH (326 mg/L · 19 gpg · 18.2 °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: 305–350 mg/L.
Mont-sur-Marchienne (Hainaut) is supplied by SWDE. The SPW reports a 2025 median of 326 mg/L CaCO₃, from 305 to 350 mg/L by zone, which is very hard. The range is tight. Limescale shows quickly on shower screens and in the kettle.
Belgian suppliers report hardness in °f (French degrees); 1 °f = 10 mg/L CaCO₃.
Water data
| Total hardness | 32.5 °fH |
|---|---|
| Utility | SWDE |
How Mont-sur-Marchienne compares
- Tap water in Mont-sur-Marchienne is close to the median of the 1091 cities we track in Belgium (31.6 °fH).
- By hardness it ranks 513 of 1091 in Belgium (1 = hardest); 53 % of these cities have softer water.
- In Hainaut it is number 227 of 271 cities; the regional median is 38 °fH.
- Nearest city with clearly softer water: Buvrinnes, 14 km away (21.6 °fH).
- Nearest city with clearly harder water: Binche, 17 km away (46 °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 Mont-sur-Marchienne
| Brand | Setting for this water |
|---|---|
| Bosch | H05 |
| Miele | 18 °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 Mont-sur-Marchienne water hard or soft?
It is very hard: 326 mg/L as CaCO₃ (19 gpg, 18.2 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Mont-sur-Marchienne 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 Mont-sur-Marchienne water?
19 gpg, equal to 18.2 °dH, 32.5 °fH or 326 mg/L calcium carbonate.
What dishwasher salt setting should I use in Mont-sur-Marchienne?
For 326 mg/L (18.2 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Mont-sur-Marchienne?
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