Water hardness in Bruz
16.9 °fH hard
Tap water in Bruz is hard: 16.9 °fH (169 mg/L · 9.9 gpg · 9.5 °dH).
Source: Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 35047 (2026-08) · data checked 2026-10-19
Range across supply zones: 162–177 mg/L.
Bruz, near Rennes, is served by SPL Eau du Bassin Rennais, which operates many resources including the Rophémel reservoir on the Rance and the Couesnon river (according to the utility). Breton rivers drain a schist bedrock: 169 mg/L CaCO₃, ranging from 162 to 177 mg/L. The water is hard, with visible scale.
TH en °fH : douce < 15, moyennement dure 15–25, dure 25–35, très dure > 35 °fH (classes usuelles ARS).
Water data
| Total hardness | 16.9 °fH |
|---|---|
| Utility | Spl Ebr |
How Bruz compares
- Tap water in Bruz is 29 % softer than the median of the 33641 cities we track in France (23.9 °fH).
- By hardness it ranks 22766 of 33641 in France (1 = hardest); 32 % of these cities have softer water.
- In Ille-et-Vilaine it is number 157 of 324 cities; the regional median is 16.9 °fH.
- Nearest city with clearly softer water: Lassy, 11 km away (13 °fH).
- Nearest city with clearly harder water: Le Verger, 15 km away (22.1 °fH).
Ranking of the hardest and softest water in France →
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 Bruz
| Brand | Setting for this water |
|---|---|
| Bosch | H02 |
| Miele | 9 °dH |
| AEG / Electrolux | 2 |
| Beko | 3rd |
| 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 Bruz water hard or soft?
It is hard: 169 mg/L as CaCO₃ (9.9 gpg, 9.5 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Bruz 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 Bruz water?
9.9 gpg, equal to 9.5 °dH, 16.9 °fH or 169 mg/L calcium carbonate.
What dishwasher salt setting should I use in Bruz?
For 169 mg/L (9.5 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Bruz?
Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.
Source
Source: Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 35047 (2026-08). Method: own measurement. Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 35047 · Outdated figure? Tell us