Water hardness in Horw
12.8 °fH hard
Tap water in Horw is hard: 12.8 °fH (128 mg/L · 7.4 gpg · 7.1 °dH).
Source: Gemeinde Horw (via SVGW trinkwasser.ch) (2025) · data checked 2026-10-21
Range across supply zones: 118–137 mg/L.
In central Switzerland, drinking water comes from springs, groundwater and in part treated lake water. Gemeinde Horw reports a hardness of 127.5 mg/L CaCO₃, with values from 118.0 to 137.0 mg/L depending on the address. Kettles, shower heads and washing machine heating elements scale up noticeably, so regular descaling is worthwhile.
In der Schweiz wird meist in °fH angegeben (1 °fH = 0,56 °dH).
Water data
| Total hardness | 12.8 °fH |
|---|---|
| Utility | Gemeinde Horw |
How Horw compares
- Tap water in Horw is 52 % softer than the median of the 650 cities we track in Switzerland (26.7 °fH).
- By hardness it ranks 609 of 650 in Switzerland (1 = hardest); 6 % of these cities have softer water.
- In LU it is number 39 of 39 cities; the regional median is 24.6 °fH.
- Nearest city with clearly softer water: Erstfeld, 34 km away (8.2 °fH).
- Nearest city with clearly harder water: Hergiswil, 4 km away (18 °fH).
Ranking of the hardest and softest water in Switzerland →
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 Horw
| Brand | Setting for this water |
|---|---|
| Bosch | H01 |
| Miele | 7 °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 Horw water hard or soft?
It is hard: 128 mg/L as CaCO₃ (7.4 gpg, 7.1 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Horw safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. In der Schweiz wird meist in °fH angegeben (1 °fH = 0,56 °dH).
How many grains per gallon is Horw water?
7.4 gpg, equal to 7.1 °dH, 12.8 °fH or 128 mg/L calcium carbonate.
What dishwasher salt setting should I use in Horw?
For 128 mg/L (7.1 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Horw?
Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.
Source
Source: Gemeinde Horw (via SVGW trinkwasser.ch) (2025). Method: figure published by the water supplier. Gemeinde Horw (via SVGW trinkwasser.ch) · Outdated figure? Tell us