Water hardness in Saint-Lô
13 °fH hard
Tap water in Saint-Lô is hard: 13 °fH (130 mg/L · 7.6 gpg · 7.3 °dH).
Source: Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 50502 (2026-07) · data checked 2026-10-19
Range across supply zones: 130–162 mg/L.
Saint-Lô in Manche is served by Veolia (Centre Manche). The Cotentin bedrock is a mix of schist and granite, low in limestone, and hardness of 130 mg/L CaCO₃, ranging from 130 to 162 mg/L, is moderate to high. Scale shows in kettles.
TH en °fH : douce < 15, moyennement dure 15–25, dure 25–35, très dure > 35 °fH (classes usuelles ARS).
Water data
| Total hardness | 13 °fH |
|---|---|
| Utility | Veolia Eau - Centre Manche |
How Saint-Lô compares
- Tap water in Saint-Lô is 46 % softer than the median of the 33641 cities we track in France (23.9 °fH).
- By hardness it ranks 26207 of 33641 in France (1 = hardest); 22 % of these cities have softer water.
- In Manche it is number 320 of 435 cities; the regional median is 14.4 °fH.
- Nearest city with clearly softer water: La Barre-de-Semilly, 4 km away (7.4 °fH).
- Nearest city with clearly harder water: Canisy, 7 km away (16.6 °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 Saint-Lô
| 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 Saint-Lô water hard or soft?
It is hard: 130 mg/L as CaCO₃ (7.6 gpg, 7.3 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Saint-Lô 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 Saint-Lô water?
7.6 gpg, equal to 7.3 °dH, 13 °fH or 130 mg/L calcium carbonate.
What dishwasher salt setting should I use in Saint-Lô?
For 130 mg/L (7.3 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Saint-Lô?
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 50502 (2026-07). Method: own measurement. Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 50502 · Outdated figure? Tell us