Water hardness in Illzach
10.4 °fH moderately hard
Tap water in Illzach is moderately hard: 10.4 °fH (104 mg/L · 6.1 gpg · 5.8 °dH).
Source: Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 68154 (2026-08) · data checked 2026-10-19
Illzach in Haut-Rhin is served by the Mulhouse Alsace Agglomération water utility, which draws from the Doller catchment, the Rhine aquifer and the Lauch and Thur alluvium (according to m2A). Doller water comes from the Vosges: 104 mg/L CaCO₃, a moderate hardness.
TH en °fH : douce < 15, moyennement dure 15–25, dure 25–35, très dure > 35 °fH (classes usuelles ARS).
Water data
| Total hardness | 10.4 °fH |
|---|---|
| Utility | Regie De L'Eau M2A |
How Illzach compares
- Tap water in Illzach is 56 % softer than the median of the 33641 cities we track in France (23.9 °fH).
- By hardness it ranks 28590 of 33641 in France (1 = hardest); 15 % of these cities have softer water.
- In Haut-Rhin it is number 254 of 360 cities; the regional median is 22.6 °fH.
- Nearest city with clearly softer water: Wuenheim, 14 km away (7.1 °fH).
- Nearest city with clearly harder water: Kingersheim, 1 km away (20.5 °fH).
Ranking of the hardest and softest water in France →
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 Illzach
| Brand | Setting for this water |
|---|---|
| Bosch | H00 |
| Miele | 6 °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 Illzach water hard or soft?
It is moderately hard: 104 mg/L as CaCO₃ (6.1 gpg, 5.8 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Illzach safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. TH en °fH : douce < 15, moyennement dure 15–25, dure 25–35, très dure > 35 °fH (classes usuelles ARS).
How many grains per gallon is Illzach water?
6.1 gpg, equal to 5.8 °dH, 10.4 °fH or 104 mg/L calcium carbonate.
What dishwasher salt setting should I use in Illzach?
For 104 mg/L (5.8 °dH) check your manufacturer's table: level 2–3.
Do I need a water softener in Illzach?
Not essential; a scale inhibitor protects the heater cheaply.
Source
Source: Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 68154 (2026-08). Method: own measurement. Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 68154 · Outdated figure? Tell us