Water hardness in Sotteville-lès-Rouen
30.8 °fH very hard
Tap water in Sotteville-lès-Rouen is very hard: 30.8 °fH (308 mg/L · 18 gpg · 17.3 °dH).
Source: Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 76681 (2026-08) · data checked 2026-10-19
In Sotteville-lès-Rouen (Seine-Maritime), water from Métropole Rouen Normandie measures 308 mg/L as CaCO₃, which is very hard. Source: ARS health control (SISE-Eaux), August 2026, measured value. The figure is identical to the one published for Saint-Étienne-du-Rouvray, served by the same metropolitan authority.
TH en °fH : douce < 15, moyennement dure 15–25, dure 25–35, très dure > 35 °fH (classes usuelles ARS).
Water data
| Total hardness | 30.8 °fH |
|---|---|
| Utility | Metropole Rouen Normandie |
How Sotteville-lès-Rouen compares
- Tap water in Sotteville-lès-Rouen is 29 % harder than the median of the 33641 cities we track in France (23.9 °fH).
- By hardness it ranks 7277 of 33641 in France (1 = hardest); 78 % of these cities have softer water.
- In Seine-Maritime it is number 50 of 682 cities; the regional median is 28.5 °fH.
- Nearest city with clearly softer water: Le Manoir, 13 km away (22.5 °fH).
- Nearest city with clearly harder water: Chérence, 55 km away (39.6 °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 Sotteville-lès-Rouen
| Brand | Setting for this water |
|---|---|
| Bosch | H05 |
| Miele | 17 °dH |
| AEG / Electrolux | 4 |
| 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 Sotteville-lès-Rouen water hard or soft?
It is very hard: 308 mg/L as CaCO₃ (18 gpg, 17.3 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Sotteville-lès-Rouen 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 Sotteville-lès-Rouen water?
18 gpg, equal to 17.3 °dH, 30.8 °fH or 308 mg/L calcium carbonate.
What dishwasher salt setting should I use in Sotteville-lès-Rouen?
For 308 mg/L (17.3 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Sotteville-lès-Rouen?
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 76681 (2026-08). Method: own measurement. Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 76681 · Outdated figure? Tell us