Water hardness in Arnedo
20.9 °fH very hard
Tap water in Arnedo is very hard: 20.9 °fH (209 mg/L · 12.2 gpg · 11.7 °dH).
Source: SINAC, Ministerio de Sanidad — Información de un abastecimiento, municipio 26018 (2026-09) · data checked 2026-10-19
For Arnedo, SINAC (the Ministry of Health's water-supply system) records 209 mg/L CaCO₃ as of September 2026. Arnedo lies in the Cidacos valley in La Rioja, where the water crosses marl and gypsum that give it considerable hardness. Scale builds up regularly in kettles, taps and the washing-machine heating element, so they need frequent cleaning.
Fuentes españolas usan °fH (grados hidrotimétricos franceses) o mg/L CaCO₃.
Water data
| Total hardness | 20.9 °fH |
|---|
How Arnedo compares
- Tap water in Arnedo is close to the median of the 4988 cities we track in Spain (20.1 °fH).
- By hardness it ranks 2416 of 4988 in Spain (1 = hardest); 51 % of these cities have softer water.
- In Rioja (La) it is number 14 of 43 cities; the regional median is 12.1 °fH.
- Nearest city with clearly softer water: Villar de Arnedo, El, 10 km away (5.8 °fH).
- Nearest city with clearly harder water: Autol, 10 km away (35.7 °fH).
Ranking of the hardest and softest water in Spain →
What it means at home
- Severe scale: heater elements and washing-machine heaters fail early.
- Detergent use is very high; taps and screens coat within days.
- Dishwasher at maximum salt setting.
- An ion-exchange softener is practically essential; RO for drinking water.
How much salt will you use for softening?
Yes. At this hardness a softener pays for itself through appliance life and detergent.
Descale a coffee machine or kettle about every 1 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Arnedo
| Brand | Setting for this water |
|---|---|
| Bosch | H03 |
| Miele | 12 °dH |
| AEG / Electrolux | 3 |
| Beko | 3rd |
| Hoover | S2 |
| 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 Arnedo water hard or soft?
It is very hard: 209 mg/L as CaCO₃ (12.2 gpg, 11.7 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Arnedo 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 Arnedo water?
12.2 gpg, equal to 11.7 °dH, 20.9 °fH or 209 mg/L calcium carbonate.
What dishwasher salt setting should I use in Arnedo?
For 209 mg/L (11.7 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Arnedo?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: SINAC, Ministerio de Sanidad — Información de un abastecimiento, municipio 26018 (2026-09). Method: own measurement. SINAC, Ministerio de Sanidad — Información de un abastecimiento, municipio 26018 · Outdated figure? Tell us