Water hardness by postcode in the Netherlands
Enter your postcode: we match it to the nearest city with published hardness data and show its value, unit and source.
How the search works
Every postcode is matched to the nearest of the 654 cities in the Netherlands for which a water supplier or regulator publishes hardness. Supply areas do not follow postcode boundaries, so the result is the figure of the nearest published supply. If the match is more than 15 km away we say so, and the annual water quality report of your own supplier is the better reference. Each city page names the source document and its date and, where the supplier publishes them, the values of each supply zone.
Dutch suppliers report °dH; most networks are softened centrally to 5.6–8.4 °dH.
Regions
- Drenthe5 · 7.6 °dH
- Flevoland19 · 7.7 °dH
- Friesland103 · 7.2 °dH
- Gelderland184 · 6.7 °dH
- Limburg6 · 8.3 °dH
- Noord-Holland5 · 7.8 °dH
- North Brabant181 · 7.9 °dH
- North Holland13 · 7.9 °dH
- Overijssel58 · 7.5 °dH
- South Holland12 · 7.8 °dH
- Utrecht59 · 6.8 °dH
- Zeeland4 · 8.9 °dH
- Zuid-Holland5 · 8 °dH
Largest cities in the Netherlands
| °dH | mg/L | ||
|---|---|---|---|
| Rotterdam | 7.6 | 136 | hard |
| Amsterdam | 7.8 | 139 | hard |
| The Hague | 8.1 | 144 | hard |
| Utrecht | 6.4 | 114 | moderately hard |
| Eindhoven | 5.9 | 106 | moderately hard |
| Tilburg | 7.8 | 139 | hard |
| Breda | 9 | 160 | hard |
| Nijmegen | 8.5 | 153 | hard |
| Almere Stad | 4.6 | 83 | moderately hard |
| Haarlem | 7.9 | 141 | hard |
| Arnhem | 6.2 | 111 | moderately hard |
| 's-Hertogenbosch | 9 | 161 | hard |
| Enschede | 8.5 | 152 | hard |
| Zaanstad | 7.9 | 141 | hard |
| Amersfoort | 6 | 107 | moderately hard |
| Apeldoorn | 5.7 | 102 | moderately hard |
| Hoofddorp | 8 | 143 | hard |
| Zwolle | 7.7 | 137 | hard |
| Leeuwarden | 7.9 | 142 | hard |
| Leiden | 8 | 142 | hard |
| Dordrecht | 8.1 | 145 | hard |
| Zoetermeer | 8 | 142 | hard |
| Delft | 7.8 | 139 | hard |
| Alkmaar | 7.9 | 141 | hard |
| Hilversum | 7.2 | 129 | hard |
| Hengelo | 6.8 | 121 | hard |
| Lelystad | 5.2 | 93 | moderately hard |
| Amstelveen | 7.8 | 139 | hard |
| Roosendaal | 9.9 | 176 | hard |
| Oss | 8 | 143 | hard |
| Schiedam | 7.6 | 136 | hard |
| Spijkenisse | 7.8 | 139 | hard |
| Helmond | 11.3 | 202 | very hard |
| Vlaardingen | 7.8 | 139 | hard |
| Almelo | 10.1 | 180 | very hard |
| Zaandam | 7.9 | 141 | hard |
| Hoorn | 7.9 | 141 | hard |
| Assen | 8 | 143 | hard |
| Velsen-Zuid | 7.9 | 141 | hard |
| Ede | 6.2 | 111 | moderately hard |