Water hardness in Santa Maria da Feira
114 mg/L moderately hard
Tap water in Santa Maria da Feira is moderately hard: 114 mg/L (6.7 gpg · 6.4 °dH · 11.4 °fH).
Source: ADP - Qualidade da água para consumo humano, 2.º trimestre 2026 (Santa Maria da Feira) (2026-08) · data checked 2026-10-29
Santa Maria da Feira is supplied through ADP, which prints one hardness analysis of 114 mg/L CaCO₃ in its Q2 2026 report, at the bulk delivery point. It is one result, not an average. This is at the upper end of the moderate band and above Porto's 96 mg/L, so expect a light scale film on kettles and taps over time.
Portuguese operators report "dureza total" in mg/L CaCO₃ to ERSAR.
Water data
| Total hardness | 114 mg/L |
|---|---|
| Utility | Águas do Douro e Paiva (ADP), concelho Santa Maria da Feira |
How Santa Maria da Feira compares
- Tap water in Santa Maria da Feira is 37 % harder than the median of the 77 cities we track in Portugal (83 mg/L).
- By hardness it ranks 10 of 77 in Portugal (1 = hardest); 88 % of these cities have softer water.
- In Aveiro it is number 2 of 6 cities; the regional median is 97 mg/L.
- Nearest city with clearly softer water: Ovar, 10 km away (20 mg/L).
Ranking of the hardest and softest water in Portugal →
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 Santa Maria da Feira
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 6 °dH |
| AEG / Electrolux | 2 |
| Beko | 2nd |
| Hoover | S1 |
| LG | H1 |
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 Santa Maria da Feira water hard or soft?
It is moderately hard: 114 mg/L as CaCO₃ (6.7 gpg, 6.4 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Santa Maria da Feira safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Portuguese operators report "dureza total" in mg/L CaCO₃ to ERSAR.
How many grains per gallon is Santa Maria da Feira water?
6.7 gpg, equal to 6.4 °dH, 11.4 °fH or 114 mg/L calcium carbonate.
What dishwasher salt setting should I use in Santa Maria da Feira?
For 114 mg/L (6.4 °dH) check your manufacturer's table: level 2–3.
Do I need a water softener in Santa Maria da Feira?
Not essential; a scale inhibitor protects the heater cheaply.
Source
Source: ADP - Qualidade da água para consumo humano, 2.º trimestre 2026 (Santa Maria da Feira) (2026-08). Method: figure published by the water supplier. ADP - Qualidade da água para consumo humano, 2.º trimestre 2026 (Santa Maria da Feira) · Outdated figure? Tell us