Water hardness in O Porriño
6.6 °fH moderately hard
Tap water in O Porriño is moderately hard: 6.6 °fH (66 mg/L · 3.9 gpg · 3.7 °dH).
Source: SINAC, Ministerio de Sanidad — Información de un abastecimiento, municipio 36039 (2026-08) · data checked 2026-10-19
Range across supply zones: 57–66 mg/L.
For O Porriño, SINAC (the Ministry of Health's water-supply system) records 66.2 mg/L CaCO₃, with readings from 57 to 66.2 mg/L as of August 2026. Galicia sits on granite and schist that dissolve poorly, and its water comes from rivers and upland sources with very little calcium and magnesium. Scale builds up slowly; descaling the kettle and coffee machine now and then is usually enough.
Fuentes españolas usan °fH (grados hidrotimétricos franceses) o mg/L CaCO₃.
Water data
| Total hardness | 6.6 °fH |
|---|
How O Porriño compares
- Tap water in O Porriño is 67 % softer than the median of the 4988 cities we track in Spain (20.1 °fH).
- By hardness it ranks 3991 of 4988 in Spain (1 = hardest); 20 % of these cities have softer water.
- In Pontevedra it is number 1 of 46 cities; the regional median is 1.8 °fH.
- Nearest city with clearly softer water: Tui, 7 km away (1.9 °fH).
- Nearest city with clearly harder water: Bóveda, 110 km away (8.6 °fH).
Ranking of the hardest and softest water in Spain →
What it means at home
- Visible kettle scale every few weeks; vinegar or citric acid is enough.
- Water heater and washing machine: some long-term scale; a scale inhibitor slows it.
- Dishwasher: medium salt setting.
- Softener optional; pays off mainly with a gas boiler or tankless heater.
How much salt will you use for softening?
Optional. A scale inhibitor or a small softener protects the heater; soap savings are modest.
Descale a coffee machine or kettle about every 3 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in O Porriño
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 4 °dH |
| AEG / Electrolux | 1 |
| Beko | 1st |
| Hoover | S0 |
| LG | H0 |
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 O Porriño water hard or soft?
It is moderately hard: 66 mg/L as CaCO₃ (3.9 gpg, 3.7 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in O Porriño 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 O Porriño water?
3.9 gpg, equal to 3.7 °dH, 6.6 °fH or 66 mg/L calcium carbonate.
What dishwasher salt setting should I use in O Porriño?
For 66 mg/L (3.7 °dH) check your manufacturer's table: level 2–3.
Do I need a water softener in O Porriño?
Not essential; a scale inhibitor protects the heater cheaply.
Source
Source: SINAC, Ministerio de Sanidad — Información de un abastecimiento, municipio 36039 (2026-08). Method: own measurement. SINAC, Ministerio de Sanidad — Información de un abastecimiento, municipio 36039 · Outdated figure? Tell us