Water hardness in Siřem
1.38 mmol/L hard
Tap water in Siřem is hard: 1.38 mmol/L (138 mg/L · 8.1 gpg · 7.7 °dH).
Source: SčVK, Moje obec – kvalita vody (aktuální hodnoty) (2026) · data checked 2026-10-21
Siřem is supplied through the network of Severočeské vodovody a kanalizace (SčVK), which draws on reservoirs and groundwater across northern Bohemia; the exact source for Siřem is not confirmed here. The reported value is 138.1 mg/L CaCO₃, in the hard band. Expect limescale on kettles, taps and heating elements; descaling every few weeks is advisable.
Czech suppliers report "Vápník a hořčík" in mmol/L; the recommended range is 2–3.5 mmol/L.
Water data
| Total hardness | 1.38 mmol/L |
|---|---|
| Calcium (mg/L) | 39 |
| Magnesium (mg/L) | 9.8 |
| Utility | Severočeské vodovody a kanalizace, a.s. (SčVK) |
How Siřem compares
- Tap water in Siřem is 15 % harder than the median of the 1516 cities we track in Czechia (1.2 mmol/L).
- By hardness it ranks 525 of 1516 in Czechia (1 = hardest); 65 % of these cities have softer water.
- In Ústecký kraj it is number 300 of 631 cities; the regional median is 1.31 mmol/L.
- Nearest city with clearly softer water: Čejkovice, 10 km away (0.83 mmol/L).
- Nearest city with clearly harder water: Měcholupy, 4 km away (4.71 mmol/L).
Ranking of the hardest and softest water in Czechia →
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 Siřem
| Brand | Setting for this water |
|---|---|
| Bosch | H01 |
| Miele | 8 °dH |
| AEG / Electrolux | 2 |
| Beko | 2nd |
| 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 Siřem water hard or soft?
It is hard: 138 mg/L as CaCO₃ (8.1 gpg, 7.7 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Siřem 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 Siřem water?
8.1 gpg, equal to 7.7 °dH, 13.8 °fH or 138 mg/L calcium carbonate.
What dishwasher salt setting should I use in Siřem?
For 138 mg/L (7.7 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Siřem?
Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.
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