Data from 495 communes. National average: 30°fH. Source: SWDE, VIVAQUA and VMM 2024.
Data: SWDE (Wallonia), De Watergroep / VMM (Flanders), VIVAQUA (Brussels) — 2024. Click a province to explore cities.
Belgium has some of the hardest tap water in Western Europe. The average hardness is around 30°fH, well above the European soft-water benchmark of 15°fH. Flanders and Wallonia draw water from very different sources, creating large regional disparities.
In Flanders, De Watergroep distributes moderately hard water (16–25°fH) in most areas. In Wallonia, SWDE supplies water ranging from very soft (<10°fH) in the Ardennes to very hard (>45°fH) in parts of Hainaut. Brussels (VIVAQUA) sits around 32–39°fH.