Water Hardness Atlas ZIP / postcode

Water hardness in Le Havre

24.2 °fH very hard

Tap water in Le Havre is very hard: 24.2 °fH (242 mg/L · 14.1 gpg · 13.6 °dH).

<6060–120120–180>180 mg/L

Source: Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 76351 (2026-08) · data checked 2026-10-19

Range across supply zones: 240–248 mg/L.

In the Pays de Caux around Le Havre, drinking water comes mainly from the chalk aquifer. Norman chalk, almost pure limestone, gives hard water: 242.0 mg/L CaCO₃, between 240.0 and 248.0 mg/L. Plan regular descaling of appliances.

TH en °fH : douce < 15, moyennement dure 15–25, dure 25–35, très dure > 35 °fH (classes usuelles ARS).

Water data

Total hardness24.2 °fH
UtilityLhsm

How Le Havre compares

Ranking of the hardest and softest water in France →

What it means at home

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 Le Havre

BrandSetting for this water
BoschH04
Miele14 °dH
AEG / Electrolux3
Beko4th
HooverS2
LGH2

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 Le Havre water hard or soft?

It is very hard: 242 mg/L as CaCO₃ (14.1 gpg, 13.6 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.

Is tap water in Le Havre 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 Le Havre water?

14.1 gpg, equal to 13.6 °dH, 24.2 °fH or 242 mg/L calcium carbonate.

What dishwasher salt setting should I use in Le Havre?

For 242 mg/L (13.6 °dH) check your manufacturer's table: maximum level (5–7).

Do I need a water softener in Le Havre?

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 76351 (2026-08). Method: own measurement. Ministère de la Santé (ARS), contrôle sanitaire SISE-Eaux, commune 76351 · Outdated figure? Tell us

Nearby cities

Harfleur24.1 °fHOcteville-sur-Mer25.2 °fHMontivilliers27.4 °fHFontenay25.2 °fHGonfreville-l'Orcher25.1 °fHÉpouville27.8 °fH
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