Water hardness in Petroúpolis
150 mg/L hard
Tap water in Petroúpolis 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
Petroúpolis is in the Attica basin and is supplied through the EYDAP network. The published 2025 compliance figure is 150 mg/L as CaCO₃, which falls in the hard category. Much of Attica's mains water is drawn from reservoirs in central Greece, where limestone-rich catchments add dissolved calcium and magnesium. Expect limescale on kettles, shower screens 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 Petroúpolis compares
- Tap water in Petroúpolis 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, 49 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 Petroúpolis
| 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 Petroúpolis 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 Petroúpolis 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 Petroúpolis 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 Petroúpolis?
For 150 mg/L (8.4 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Petroúpolis?
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