Water Hardness and Quality in North Hillingdon
Supplied by Affinity Water · Uxbridge (AF059)
North Hillingdon has very hard water with quality that meets all UK drinking water standards.
Check a specific postcode in North Hillingdon
Water Quality Scorecard
Total Hardness
Guideline: 150+ mg/l is considered hard
308mg/l CaCO₃
UK Average: 197.72 mg/l CaCO₃Well Above Average
LowAverageHigh
pH Level
UK Standard: 6.5 – 9.5
7.3pH units
UK Average: 7.43 pH unitsBelow Average
LowAverageHigh
Free Chlorine
Guideline: below 1 mg/l
0.7mg/l
UK Average: 0.45 mg/lWell Above Average
LowAverageHigh
Nitrate
UK Standard: max 50 mg/l
32mg/l
UK Average: 16.9 mg/lWell Above Average
LowAverageHigh
Lead
UK Standard: max 10 µg/l
0.67µg/l
UK Average: 1.08 µg/lAverage
LowAverageHigh
Fluoride
UK Standard: max 1.5 mg/l
0.12mg/l
UK Average: 0.19 mg/lAverage
LowAverageHigh
Water Hardness in North Hillingdon
Hardness is the most searched water quality metric. It affects limescale buildup in kettles, boilers, and pipes.
308mg/l CaCO₃Very Hard
Soft
Mod. Soft
Slightly Hard
Mod. Hard
Hard
Very Hard
North Hillingdon has hard water at 308 mg/l. You will likely experience significant limescale buildup in kettles, boilers, and on bathroom surfaces. Many residents in your area use water softeners or anti-limescale products.
Water Source Information
- Water Company
- Affinity Water
- Supply Zone
- Uxbridge (AF059)
- Source Type
- Groundwater
- Treatment Works
- Uxbridge Treatment Works
- Last Tested
- 2025-12-31
- Data Source
- Affinity Water
Frequently Asked Questions
Is the water hard in North Hillingdon?▾
Yes, North Hillingdon has hard water at 308 mg/l CaCO₃. This is classified as "Very Hard" on the standard scale. You may notice limescale buildup in kettles and on taps.
Is North Hillingdon tap water safe to drink?▾
Yes, tap water in North Hillingdon is safe to drink. It is treated and tested by Affinity Water and meets all UK Drinking Water Inspectorate standards. All tested parameters are within regulatory limits.
What is the water hardness in North Hillingdon?▾
The water hardness in North Hillingdon is 308 mg/l CaCO₃, which is classified as "Very Hard". This is above the UK national average of 170 mg/l.
Who supplies water to North Hillingdon?▾
Water in North Hillingdon is supplied by Affinity Water, which serves the South East England region. The water comes from underground aquifers and is treated at Uxbridge Treatment Works.