Water hardness in Kostelec nad Ohří
4.6 mmol/L very hard
Tap water in Kostelec nad Ohří is very hard: 4.6 mmol/L (460 mg/L · 26.9 gpg · 25.8 °dH).
Source: SčVK, Moje obec – kvalita vody (aktuální hodnoty) (2026) · data checked 2026-10-21
SčVK reports 460.4 mg/L hardness as CaCO₃ for Kostelec nad Ohří, one of the highest values in this batch. The village lies in the Litoměřice area of the Ústí region, but the utility page does not name the source, so we do not state the cause. At this level scale forms quickly in water heaters and kettles. Check the current value on the SčVK page before sizing a softener.
Czech suppliers report "Vápník a hořčík" in mmol/L; the recommended range is 2–3.5 mmol/L.
Water data
| Total hardness | 4.6 mmol/L |
|---|---|
| Calcium (mg/L) | 147 |
| Magnesium (mg/L) | 22.7 |
| Utility | Severočeské vodovody a kanalizace, a.s. (SčVK) |
How Kostelec nad Ohří compares
- Tap water in Kostelec nad Ohří is 283 % harder than the median of the 1516 cities we track in Czechia (1.2 mmol/L).
- By hardness it ranks 76 of 1516 in Czechia (1 = hardest); 95 % of these cities have softer water.
- In Ústecký kraj it is number 76 of 631 cities; the regional median is 1.31 mmol/L.
- Nearest city with clearly softer water: Libochovice, 4 km away (2.45 mmol/L).
- Nearest city with clearly harder water: Chotěšov, 5 km away (5.9 mmol/L).
Ranking of the hardest and softest water in Czechia →
What it means at home
- Severe scale: heater elements and washing-machine heaters fail early.
- Detergent use is very high; taps and screens coat within days.
- Dishwasher at maximum salt setting.
- An ion-exchange softener is practically essential; RO for drinking water.
How much salt will you use for softening?
Yes. At this hardness a softener pays for itself through appliance life and detergent.
Descale a coffee machine or kettle about every 1 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Kostelec nad Ohří
| Brand | Setting for this water |
|---|---|
| Bosch | H06 |
| Miele | 26 °dH |
| AEG / Electrolux | 6 |
| Beko | 6th |
| Hoover | S4 |
| LG | H4 |
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 Kostelec nad Ohří water hard or soft?
It is very hard: 460 mg/L as CaCO₃ (26.9 gpg, 25.8 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Kostelec nad Ohří safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Czech suppliers report "Vápník a hořčík" in mmol/L; the recommended range is 2–3.5 mmol/L.
How many grains per gallon is Kostelec nad Ohří water?
26.9 gpg, equal to 25.8 °dH, 46 °fH or 460 mg/L calcium carbonate.
What dishwasher salt setting should I use in Kostelec nad Ohří?
For 460 mg/L (25.8 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Kostelec nad Ohří?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: SčVK, Moje obec – kvalita vody (aktuální hodnoty) (2026). Method: figure published by the water supplier. SčVK, Moje obec – kvalita vody (aktuální hodnoty) · Outdated figure? Tell us