Water hardness in Knottingley
282 mg/L very hard
Tap water in Knottingley is very hard: 282 mg/L (16.5 gpg · 15.8 °dH · 28.2 °fH).
Source: Yorkshire Water — domestic drinking water quality (Stream open data, CC BY) (2025-09) · data checked 2026-10-20
Range across supply zones: 281–302 mg/L.
Yorkshire Water supplies Knottingley from a network that blends reservoir, river and borehole sources, and the company links harder water in the east of the region to its borehole and groundwater supplies. Reported hardness is 282.2 mg/L CaCO₃, ranging from 281.2 to 301.7 mg/L between supply zones. The harder supply reflects borehole and groundwater sources, which pick up calcium and magnesium from the rock; it is hard to very hard water, so scale builds quickly on kettles, showers and heating elements and shortens appliance life unless treated.
UK suppliers report mg/L CaCO₃ and often Clark degrees (1 °Clark = 14.25 mg/L).
Water data
| Total hardness | 282 mg/L |
|---|---|
| Utility | Yorkshire Water |
How Knottingley compares
- Tap water in Knottingley is 53 % harder than the median of the 471 cities we track in the United Kingdom (185 mg/L).
- By hardness it ranks 128 of 471 in the United Kingdom (1 = hardest); 72 % of these cities have softer water.
- In Wakefield it is number 4 of 12 cities; the regional median is 276 mg/L.
- Nearest city with clearly softer water: Normanton, 11 km away (225 mg/L).
- Nearest city with clearly harder water: Cottingham, 56 km away (371 mg/L).
Ranking of the hardest and softest water in the United Kingdom →
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 Knottingley
| Brand | Setting for this water |
|---|---|
| Bosch | H04 |
| Miele | 16 °dH |
| AEG / Electrolux | 4 |
| Beko | 5th |
| Hoover | S2 |
| 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 Knottingley water hard or soft?
It is very hard: 282 mg/L as CaCO₃ (16.5 gpg, 15.8 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Knottingley 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 Knottingley water?
16.5 gpg, equal to 15.8 °dH, 28.2 °fH or 282 mg/L calcium carbonate.
What dishwasher salt setting should I use in Knottingley?
For 282 mg/L (15.8 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Knottingley?
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) (2025-09). Method: own measurement. Yorkshire Water — domestic drinking water quality (Stream open data, CC BY) · Outdated figure? Tell us