Water hardness in Schiedam
7.6 °dH hard
Tap water in Schiedam is hard: 7.6 °dH (136 mg/L · 7.9 gpg · 13.6 °fH).
Source: Evides, waterhardheid per postcode (PC4 3111) (2026) · data checked 2026-10-29
Evides reports 135.7 mg/L CaCO3 for postcode area 3111 in Schiedam, in the hard category. Limescale builds up on heating elements, so descaling a kettle or coffee machine every few months is a reasonable routine.
Dutch suppliers report °dH; most networks are softened centrally to 5.6–8.4 °dH.
Water data
| Total hardness | 7.6 °dH |
|---|---|
| Utility | Evides |
How Schiedam compares
- Tap water in Schiedam is close to the median of the 654 cities we track in the Netherlands (7.5 °dH).
- By hardness it ranks 304 of 654 in the Netherlands (1 = hardest); 53 % of these cities have softer water.
- In South Holland it is number 11 of 12 cities; the regional median is 7.8 °dH.
- Nearest city with clearly softer water: Herwijnen, 52 km away (5.8 °dH).
- Nearest city with clearly harder water: Werkendam, 37 km away (10.6 °dH).
Ranking of the hardest and softest water in the Netherlands →
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 Schiedam
| Brand | Setting for this water |
|---|---|
| Bosch | H01 |
| Miele | 8 °dH |
| AEG / Electrolux | 2 |
| Beko | 2nd |
| 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 Schiedam water hard or soft?
It is hard: 136 mg/L as CaCO₃ (7.9 gpg, 7.6 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Schiedam safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Dutch suppliers report °dH; most networks are softened centrally to 5.6–8.4 °dH.
How many grains per gallon is Schiedam water?
7.9 gpg, equal to 7.6 °dH, 13.6 °fH or 136 mg/L calcium carbonate.
What dishwasher salt setting should I use in Schiedam?
For 136 mg/L (7.6 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Schiedam?
Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.
Source
Source: Evides, waterhardheid per postcode (PC4 3111) (2026). Method: figure published by the water supplier. Evides, waterhardheid per postcode (PC4 3111) · Outdated figure? Tell us