Water hardness in Hämeenlinna
3.6 °dH moderately hard
Tap water in Hämeenlinna is moderately hard: 3.6 °dH (65 mg/L · 3.8 gpg · 6.5 °fH).
Source: HS-Vesi, Käyttöveden laatu, Kovuus (mmol/l) per area (web page) (2026) · data checked 2026-10-21
Range across supply zones: 60–70 mg/L.
HS-Vesi, the regional water company, gives 0.6 to 0.7 mmol/L for the Hämeenlinna area on its water-quality page, updated in April 2026. The same table covers neighbouring municipalities such as Akaa and Hattula, which have their own values. The page gives a range only, so the shown figure is its midpoint. Scale in appliances should be limited.
Finnish waterworks report hardness in °dH; most supplies are soft.
Water data
| Total hardness | 3.6 °dH |
|---|---|
| Utility | HS-Vesi (Hämeenlinnan Seudun Vesi Oy) |
How Hämeenlinna compares
- Tap water in Hämeenlinna is 5 % harder than the median of the 76 cities we track in Finland (3.5 °dH).
- By hardness it ranks 33 of 76 in Finland (1 = hardest); 57 % of these cities have softer water.
- Nearest city with clearly softer water: Hollola, 56 km away (1.8 °dH).
- Nearest city with clearly harder water: Forssa, 50 km away (6 °dH).
Ranking of the hardest and softest water in Finland →
What it means at home
- Visible kettle scale every few weeks; vinegar or citric acid is enough.
- Water heater and washing machine: some long-term scale; a scale inhibitor slows it.
- Dishwasher: medium salt setting.
- Softener optional; pays off mainly with a gas boiler or tankless heater.
How much salt will you use for softening?
Optional. A scale inhibitor or a small softener protects the heater; soap savings are modest.
Descale a coffee machine or kettle about every 3 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Hämeenlinna
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 4 °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 Hämeenlinna water hard or soft?
It is moderately hard: 65 mg/L as CaCO₃ (3.8 gpg, 3.6 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Hämeenlinna safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Finnish waterworks report hardness in °dH; most supplies are soft.
How many grains per gallon is Hämeenlinna water?
3.8 gpg, equal to 3.6 °dH, 6.5 °fH or 65 mg/L calcium carbonate.
What dishwasher salt setting should I use in Hämeenlinna?
For 65 mg/L (3.6 °dH) check your manufacturer's table: level 2–3.
Do I need a water softener in Hämeenlinna?
Not essential; a scale inhibitor protects the heater cheaply.
Source
Source: HS-Vesi, Käyttöveden laatu, Kovuus (mmol/l) per area (web page) (2026). Method: computed from supplier's calcium and magnesium. HS-Vesi, Käyttöveden laatu, Kovuus (mmol/l) per area (web page) · Outdated figure? Tell us