Water hardness in Zarautz
14.4 °fH hard
Tap water in Zarautz is hard: 14.4 °fH (144 mg/L · 8.4 gpg · 8.1 °dH).
Source: SINAC, Ministerio de Sanidad — Información de un abastecimiento, municipio 20079 (2025-03) · data checked 2026-10-19
Range across supply zones: 139–172 mg/L.
For Zarautz, SINAC (the Ministry of Health's water-supply system) records 144 mg/L CaCO₃, with readings from 139 to 172 mg/L as of March 2025. In the Basque Country water comes from reservoirs and springs on the Cantabrian side, with limestone and marl in the massifs and sandstone elsewhere; hardness runs from low to moderate. Some scale shows on shower screens, kettles and taps, and a scale-reduction filter can be reasonable if you want to protect appliances.
Fuentes españolas usan °fH (grados hidrotimétricos franceses) o mg/L CaCO₃.
Water data
| Total hardness | 14.4 °fH |
|---|
How Zarautz compares
- Tap water in Zarautz is 28 % softer than the median of the 4988 cities we track in Spain (20.1 °fH).
- By hardness it ranks 3090 of 4988 in Spain (1 = hardest); 38 % of these cities have softer water.
- In Guipúzcoa it is number 55 of 86 cities; the regional median is 15.3 °fH.
- Nearest city with clearly softer water: Usurbil, 10 km away (5 °fH).
- Nearest city with clearly harder water: Aizarnazabal, 6 km away (20.9 °fH).
Ranking of the hardest and softest water in Spain →
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 Zarautz
| Brand | Setting for this water |
|---|---|
| Bosch | H01 |
| Miele | 8 °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 Zarautz water hard or soft?
It is hard: 144 mg/L as CaCO₃ (8.4 gpg, 8.1 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Zarautz safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Fuentes españolas usan °fH (grados hidrotimétricos franceses) o mg/L CaCO₃.
How many grains per gallon is Zarautz water?
8.4 gpg, equal to 8.1 °dH, 14.4 °fH or 144 mg/L calcium carbonate.
What dishwasher salt setting should I use in Zarautz?
For 144 mg/L (8.1 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Zarautz?
Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.
Source
Source: SINAC, Ministerio de Sanidad — Información de un abastecimiento, municipio 20079 (2025-03). Method: own measurement. SINAC, Ministerio de Sanidad — Información de un abastecimiento, municipio 20079 · Outdated figure? Tell us