Water hardness in Athens
150 mg/L hard
Tap water in Athens is hard: 150 mg/L (8.8 gpg · 8.4 °dH · 15 °fH).
Source: EYDAP - Δεδομένα ελέγχου ποιότητας πόσιμου νερού, δίκτυο ΕΥΔΑΠ 2025 (2025) · data checked 2026-10-29
Athens is supplied by EYDAP, which draws mostly on surface reservoirs in central Greece, chiefly Mornos and Evinos. The 2025 EYDAP certificate reports 150 mg/L as CaCO₃, which falls in the hard band. Much of the surrounding geology is limestone, which is why the water carries calcium. Expect scale on kettles and heating elements.
Greek utilities report total hardness in mg/L CaCO₃.
Water data
| Total hardness | 150 mg/L |
|---|---|
| Calcium (mg/L) | 46 |
| Magnesium (mg/L) | 8.5 |
| Utility | EYDAP |
How Athens compares
- Tap water in Athens is 37 % softer than the median of the 134 cities we track in Greece (237 mg/L).
- By hardness it ranks 101 of 134 in Greece (1 = hardest); 7 % of these cities have softer water.
- In Attica it is number 1 of 25 cities; the regional median is 150 mg/L.
- Nearest city with clearly harder water: Agioi Theodoroi, 52 km away (412 mg/L).
Ranking of the hardest and softest water in Greece →
What it means at home
- Fast scale on taps, shower screens and kettle; white spots on glassware.
- Water heater: efficiency loss and element failures within years if unprotected.
- Dry skin and dull hair after showering are common.
- Softener recommended; jug or reverse osmosis for drinking.
How much salt will you use for softening?
Recommended, especially with a heater or boiler: scale cuts efficiency and shortens its life.
Descale a coffee machine or kettle about every 2 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Athens
| Brand | Setting for this water |
|---|---|
| Bosch | H02 |
| Miele | 8 °dH |
| AEG / Electrolux | 2 |
| Beko | 3rd |
| Hoover | S1 |
| 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 Athens water hard or soft?
It is hard: 150 mg/L as CaCO₃ (8.8 gpg, 8.4 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Athens safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Greek utilities report total hardness in mg/L CaCO₃.
How many grains per gallon is Athens water?
8.8 gpg, equal to 8.4 °dH, 15 °fH or 150 mg/L calcium carbonate.
What dishwasher salt setting should I use in Athens?
For 150 mg/L (8.4 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Athens?
Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.
Source
Source: EYDAP - Δεδομένα ελέγχου ποιότητας πόσιμου νερού, δίκτυο ΕΥΔΑΠ 2025 (2025). Method: figure published by the water supplier. EYDAP - Δεδομένα ελέγχου ποιότητας πόσιμου νερού, δίκτυο ΕΥΔΑΠ 2025 · Outdated figure? Tell us