Water hardness in Carnaxide
42 mg/L soft
Tap water in Carnaxide is soft: 42 mg/L (2.4 gpg · 2.3 °dH · 4.2 °fH).
Source: SMAS Sintra - Entrega ao concelho de Oeiras, 1º trimestre 2026 (2026) · data checked 2026-10-29
Carnaxide is in Oeiras, which receives EPAL water delivered in bulk. The Q1 2026 report prints one hardness analysis, 41.5 mg/L CaCO₃, at the delivery point, and the Q2 2026 report has none. The local network may differ slightly from that point. Soft water like this means little scale and low detergent needs.
Portuguese operators report "dureza total" in mg/L CaCO₃ to ERSAR.
Water data
| Total hardness | 42 mg/L |
|---|---|
| Utility | SMAS Sintra (bulk to Oeiras/Amadora) |
How Carnaxide compares
- Tap water in Carnaxide is 50 % softer than the median of the 77 cities we track in Portugal (83 mg/L).
- By hardness it ranks 64 of 77 in Portugal (1 = hardest); 11 % of these cities have softer water.
- In Lisboa it is number 8 of 13 cities; the regional median is 50 mg/L.
- Nearest city with clearly softer water: Vila Franca de Xira, 34 km away (15 mg/L).
- Nearest city with clearly harder water: Pontinha, 6 km away (86 mg/L).
Ranking of the hardest and softest water in Portugal →
What it means at home
- Little or no limescale in kettles, water heaters or washing machines.
- Soap lathers easily; water does not dry skin or hair.
- Dishwasher: salt setting at minimum or off.
- No softener needed; a jug filter only changes taste.
How much salt will you use for softening?
No. Water this soft does not need softening.
Descale a coffee machine or kettle about every 6 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Carnaxide
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 2 °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 Carnaxide water hard or soft?
It is soft: 42 mg/L as CaCO₃ (2.4 gpg, 2.3 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Carnaxide 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 Carnaxide water?
2.4 gpg, equal to 2.3 °dH, 4.2 °fH or 42 mg/L calcium carbonate.
What dishwasher salt setting should I use in Carnaxide?
For 42 mg/L (2.3 °dH) check your manufacturer's table: level 0–1, usually no salt.
Do I need a water softener in Carnaxide?
No. With soft water a softener adds nothing.
Source
Source: SMAS Sintra - Entrega ao concelho de Oeiras, 1º trimestre 2026 (2026). Method: figure published by the water supplier. SMAS Sintra - Entrega ao concelho de Oeiras, 1º trimestre 2026 · Outdated figure? Tell us