Water hardness in Saku
1.2 mmol/L hard
Tap water in Saku is hard: 1.2 mmol/L (120 mg/L · 7 gpg · 6.7 °dH).
Source: Terviseamet, veevärkide veeproovid (avalikud andmed) 2021–2025 (2025-09) · data checked 2026-10-20
Range across supply zones: 74–180 mg/L.
Estonian laboratories report total hardness (üldkaredus) in mmol/L or mg-eq/L (1 mmol/L = 2 mg-eq/L = 100 mg/L CaCO₃); groundwater supplies are mostly hard.
Water data
| Total hardness | 1.2 mmol/L |
|---|
How Saku compares
- Tap water in Saku is 48 % softer than the median of the 28 cities we track in Estonia (2.32 mmol/L).
- By hardness it ranks 25 of 28 in Estonia (1 = hardest); 11 % of these cities have softer water.
- In Harjumaa it is number 9 of 11 cities; the regional median is 2.02 mmol/L.
- Nearest city with clearly softer water: Laagri, 6 km away (0.87 mmol/L).
- Nearest city with clearly harder water: Peetri, 13 km away (3.4 mmol/L).
Ranking of the hardest and softest water in Estonia →
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 Saku
| Brand | Setting for this water |
|---|---|
| Bosch | H01 |
| Miele | 7 °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 Saku water hard or soft?
It is hard: 120 mg/L as CaCO₃ (7 gpg, 6.7 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Saku safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Estonian laboratories report total hardness (üldkaredus) in mmol/L or mg-eq/L (1 mmol/L = 2 mg-eq/L = 100 mg/L CaCO₃); groundwater supplies are mostly hard.
How many grains per gallon is Saku water?
7 gpg, equal to 6.7 °dH, 12 °fH or 120 mg/L calcium carbonate.
What dishwasher salt setting should I use in Saku?
For 120 mg/L (6.7 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Saku?
Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.
Source
Source: Terviseamet, veevärkide veeproovid (avalikud andmed) 2021–2025 (2025-09). Method: own measurement. Terviseamet, veevärkide veeproovid (avalikud andmed) 2021–2025 · Outdated figure? Tell us