Water Hardness and Quality in Harefield
Supplied by Affinity Water · Rickmansworth/Gerrards Cross (AF045)
Harefield has hard water with quality that meets all UK drinking water standards.
Check a specific postcode in Harefield
Water Quality Scorecard
Total Hardness
Guideline: 150+ mg/l is considered hard
283mg/l CaCO₃
UK Average: 197.72 mg/l CaCO₃Well Above Average
LowAverageHigh
pH Level
UK Standard: 6.5 – 9.5
7pH units
UK Average: 7.43 pH unitsWell Below Average
LowAverageHigh
Free Chlorine
Guideline: below 1 mg/l
0.36mg/l
UK Average: 0.45 mg/lBelow Average
LowAverageHigh
Nitrate
UK Standard: max 50 mg/l
22.3mg/l
UK Average: 16.9 mg/lAbove Average
LowAverageHigh
Lead
UK Standard: max 10 µg/l
1.31µg/l
UK Average: 1.08 µg/lWell Above Average
LowAverageHigh
Fluoride
UK Standard: max 1.5 mg/l
0.113mg/l
UK Average: 0.19 mg/lAverage
LowAverageHigh
Water Hardness in Harefield
Hardness is the most searched water quality metric. It affects limescale buildup in kettles, boilers, and pipes.
283mg/l CaCO₃Hard
Soft
Mod. Soft
Slightly Hard
Mod. Hard
Hard
Very Hard
Harefield has hard water at 283 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
- Rickmansworth/Gerrards Cross (AF045)
- Source Type
- Groundwater
- Treatment Works
- Rickmansworth/Gerrards Cross Treatment Works
- Last Tested
- 2025-12-31
- Data Source
- Affinity Water
Frequently Asked Questions
Is the water hard in Harefield?▾
Yes, Harefield has hard water at 283 mg/l CaCO₃. This is classified as "Hard" on the standard scale. You may notice limescale buildup in kettles and on taps.
Is Harefield tap water safe to drink?▾
Yes, tap water in Harefield 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 Harefield?▾
The water hardness in Harefield is 283 mg/l CaCO₃, which is classified as "Hard". This is above the UK national average of 170 mg/l.
Who supplies water to Harefield?▾
Water in Harefield is supplied by Affinity Water, which serves the South East England region. The water comes from underground aquifers and is treated at Rickmansworth/Gerrards Cross Treatment Works.