Water hardness in Opwijk
17.2 °fH hard
Tap water in Opwijk is hard: 17.2 °fH (172 mg/L · 10 gpg · 9.6 °dH).
Source: VMM, Kwaliteit van het drinkwater per leveringsgebied 2024, bijlage 2 (mediane concentratie) (2024) · data checked 2026-10-19
Range across supply zones: 163–180 mg/L.
Opwijk (Flemish Brabant) is supplied by De Watergroep. The VMM median for 2024 is 172 mg/L CaCO₃, between 163 and 180 mg/L: hard water in a narrow range. The data do not detail the water's origin. Scale remains visible on taps and in the kettle.
Belgian suppliers report hardness in °f (French degrees); 1 °f = 10 mg/L CaCO₃.
Water data
| Total hardness | 17.2 °fH |
|---|---|
| Utility | De Watergroep |
How Opwijk compares
- Tap water in Opwijk is 46 % softer than the median of the 1091 cities we track in Belgium (31.6 °fH).
- By hardness it ranks 848 of 1091 in Belgium (1 = hardest); 22 % of these cities have softer water.
- In Vlaams-Brabant it is number 50 of 59 cities; the regional median is 26.6 °fH.
- Nearest city with clearly softer water: Tessenderlo, 64 km away (11.4 °fH).
- Nearest city with clearly harder water: Londerzeel, 9 km away (22.2 °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 Opwijk
| Brand | Setting for this water |
|---|---|
| Bosch | H02 |
| Miele | 10 °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 Opwijk water hard or soft?
It is hard: 172 mg/L as CaCO₃ (10 gpg, 9.6 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Opwijk 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 Opwijk water?
10 gpg, equal to 9.6 °dH, 17.2 °fH or 172 mg/L calcium carbonate.
What dishwasher salt setting should I use in Opwijk?
For 172 mg/L (9.6 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Opwijk?
Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.
Source
Source: VMM, Kwaliteit van het drinkwater per leveringsgebied 2024, bijlage 2 (mediane concentratie) (2024). Method: figure published by the water supplier. VMM, Kwaliteit van het drinkwater per leveringsgebied 2024, bijlage 2 (mediane concentratie) · Outdated figure? Tell us