Water hardness in Sion Mills
120 mg/L moderately hard
Tap water in Sion Mills is moderately hard: 120 mg/L (7 gpg · 6.7 °dH · 12 °fH).
Source: NI Water, customer tap results 2024,2025 (OpenDataNI, OGL v3.0) (2025-11) · data checked 2026-10-20
UK suppliers report mg/L CaCO₃ and often Clark degrees (1 °Clark = 14.25 mg/L).
Water data
| Total hardness | 120 mg/L |
|---|---|
| Utility | Northern Ireland Water |
How Sion Mills compares
- Tap water in Sion Mills is 35 % softer than the median of the 471 cities we track in the United Kingdom (185 mg/L).
- By hardness it ranks 305 of 471 in the United Kingdom (1 = hardest); 35 % of these cities have softer water.
- In Northern Ireland it is number 47 of 110 cities; the regional median is 100 mg/L.
- Nearest city with clearly softer water: Castlederg, 12 km away (83 mg/L).
- Nearest city with clearly harder water: Ballinamallard, 44 km away (151 mg/L).
Ranking of the hardest and softest water in the United Kingdom →
What it means at home
- Visible kettle scale every few weeks; vinegar or citric acid is enough.
- Water heater and washing machine: some long-term scale; a scale inhibitor slows it.
- Dishwasher: medium salt setting.
- Softener optional; pays off mainly with a gas boiler or tankless heater.
How much salt will you use for softening?
Optional. A scale inhibitor or a small softener protects the heater; soap savings are modest.
Descale a coffee machine or kettle about every 3 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Sion Mills
| Brand | Setting for this water |
|---|---|
| Bosch | H01 |
| Miele | 7 °dH |
| AEG / Electrolux | 2 |
| Beko | 2nd |
| Hoover | S1 |
| LG | H1 |
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 Sion Mills water hard or soft?
It is moderately hard: 120 mg/L as CaCO₃ (7 gpg, 6.7 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Sion Mills 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 Sion Mills water?
7 gpg, equal to 6.7 °dH, 12 °fH or 120 mg/L calcium carbonate.
What dishwasher salt setting should I use in Sion Mills?
For 120 mg/L (6.7 °dH) check your manufacturer's table: level 2–3.
Do I need a water softener in Sion Mills?
Not essential; a scale inhibitor protects the heater cheaply.
Source
Source: NI Water, customer tap results 2024,2025 (OpenDataNI, OGL v3.0) (2025-11). Method: own measurement. NI Water, customer tap results 2024,2025 (OpenDataNI, OGL v3.0) · Outdated figure? Tell us