Water hardness in San Martín de la Vega
4.7 °fH soft
Tap water in San Martín de la Vega is soft: 4.7 °fH (47 mg/L · 2.7 gpg · 2.6 °dH).
Source: SINAC, Ministerio de Sanidad — Información de un abastecimiento, municipio 28132 (2026-04) · data checked 2026-10-19
For San Martín de la Vega, SINAC (the Ministry of Health's water-supply system) records 47 mg/L CaCO₃ as of April 2026. Madrid is supplied mostly by Canal de Isabel II, which draws from mountain reservoirs on granite and gneiss; that rock barely dissolves, so the water is lightly mineralised. This is very soft water: it leaves almost no limescale, and home treatment is seldom needed.
Fuentes españolas usan °fH (grados hidrotimétricos franceses) o mg/L CaCO₃.
Water data
| Total hardness | 4.7 °fH |
|---|
How San Martín de la Vega compares
- Tap water in San Martín de la Vega is 77 % softer than the median of the 4988 cities we track in Spain (20.1 °fH).
- By hardness it ranks 4200 of 4988 in Spain (1 = hardest); 16 % of these cities have softer water.
- In Madrid it is number 25 of 114 cities; the regional median is 3.8 °fH.
- Nearest city with clearly softer water: Valdelaguna, 17 km away (2.7 °fH).
- Nearest city with clearly harder water: Pinto, 11 km away (6.3 °fH).
Ranking of the hardest and softest water in Spain →
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 San Martín de la Vega
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 3 °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 San Martín de la Vega water hard or soft?
It is soft: 47 mg/L as CaCO₃ (2.7 gpg, 2.6 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in San Martín de la Vega 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 San Martín de la Vega water?
2.7 gpg, equal to 2.6 °dH, 4.7 °fH or 47 mg/L calcium carbonate.
What dishwasher salt setting should I use in San Martín de la Vega?
For 47 mg/L (2.6 °dH) check your manufacturer's table: level 0–1, usually no salt.
Do I need a water softener in San Martín de la Vega?
No. With soft water a softener adds nothing.
Source
Source: SINAC, Ministerio de Sanidad — Información de un abastecimiento, municipio 28132 (2026-04). Method: own measurement. SINAC, Ministerio de Sanidad — Información de un abastecimiento, municipio 28132 · Outdated figure? Tell us