Water hardness in Lillers
33.5 °fH very hard
Tap water in Lillers is very hard: 33.5 °fH (335 mg/L · 19.6 gpg · 18.8 °dH).
Source: Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 62516 (2026-08) · data checked 2026-10-19
Range across supply zones: 298–372 mg/L.
In Lillers (Pas-de-Calais), measured hardness is 335 mg/L CaCO₃ (33.5 °f), with a range of 298 to 372 mg/L, so the water is very hard at every sampled point. The service is run by C.A.B.B.A.L.R.; the figure comes from the ARS health-control data (SISE-Eaux, August 2026).
TH en °fH : douce < 15, moyennement dure 15–25, dure 25–35, très dure > 35 °fH (classes usuelles ARS).
Water data
| Total hardness | 33.5 °fH |
|---|---|
| Utility | C.A.B.B.A.L.R. |
How Lillers compares
- Tap water in Lillers is 40 % harder than the median of the 33641 cities we track in France (23.9 °fH).
- By hardness it ranks 4030 of 33641 in France (1 = hardest); 88 % of these cities have softer water.
- In Pas-de-Calais it is number 359 of 880 cities; the regional median is 32.9 °fH.
- Nearest city with clearly softer water: Saint-Venant, 8 km away (26.3 °fH).
- Nearest city with clearly harder water: Haverskerque, 10 km away (45.7 °fH).
Ranking of the hardest and softest water in France →
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 Lillers
| Brand | Setting for this water |
|---|---|
| Bosch | H05 |
| Miele | 19 °dH |
| AEG / Electrolux | 5 |
| Beko | 5th |
| Hoover | S3 |
| LG | H3 |
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 Lillers water hard or soft?
It is very hard: 335 mg/L as CaCO₃ (19.6 gpg, 18.8 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Lillers 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 Lillers water?
19.6 gpg, equal to 18.8 °dH, 33.5 °fH or 335 mg/L calcium carbonate.
What dishwasher salt setting should I use in Lillers?
For 335 mg/L (18.8 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Lillers?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 62516 (2026-08). Method: own measurement. Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 62516 · Outdated figure? Tell us