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Water hardness in Northallerton

270 mg/L very hard

Tap water in Northallerton is very hard: 270 mg/L (15.8 gpg · 15.1 °dH · 27 °fH).

<6060–120120–180>180 mg/L

Source: Yorkshire Water — domestic drinking water quality (Stream open data, CC BY) (2026-08) · data checked 2026-10-19

Range across supply zones: 244–286 mg/L.

The tap water in Northallerton comes from Yorkshire Water, which draws on moorland reservoirs in the west, rivers, and boreholes that are concentrated in the east of the region. Reported hardness is 269.7 mg/L CaCO₃, ranging from 243.6 to 285.7 mg/L between supply zones. The harder supply reflects borehole and groundwater sources, which pick up calcium and magnesium from the rock; expect visible limescale on taps, kettles and in boilers; a softener or scale inhibitor is worth considering, especially for hot-water systems.

UK suppliers report mg/L CaCO₃ and often Clark degrees (1 °Clark = 14.25 mg/L).

Water data

Total hardness270 mg/L
UtilityYorkshire Water

How Northallerton compares

Ranking of the hardest and softest water in the United Kingdom →

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 Northallerton

BrandSetting for this water
BoschH04
Miele15 °dH
AEG / Electrolux4
Beko4th
HooverS2
LGH3

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 Northallerton water hard or soft?

It is very hard: 270 mg/L as CaCO₃ (15.8 gpg, 15.1 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.

Is tap water in Northallerton safe to drink?

Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. UK suppliers report mg/L CaCO₃ and often Clark degrees (1 °Clark = 14.25 mg/L).

How many grains per gallon is Northallerton water?

15.8 gpg, equal to 15.1 °dH, 27 °fH or 270 mg/L calcium carbonate.

What dishwasher salt setting should I use in Northallerton?

For 270 mg/L (15.1 °dH) check your manufacturer's table: maximum level (5–7).

Do I need a water softener in Northallerton?

Yes, unless you are only passing through: scale damages appliances within a few years.

Source

Source: Yorkshire Water — domestic drinking water quality (Stream open data, CC BY) (2026-08). Method: own measurement. Yorkshire Water — domestic drinking water quality (Stream open data, CC BY) · Outdated figure? Tell us

Nearby cities

Scorton282 mg/LThirsk248 mg/LCatterick280 mg/LCatterick Garrison267 mg/LRichmond270 mg/LRipon65 mg/L
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