Water Hardness and Quality in Epsom
Supplied by Thames Water · Epsom North (SLW34)
Epsom has very hard water with quality that meets all UK drinking water standards.
Check a specific postcode in Epsom
Water Quality Scorecard
Total Hardness
Guideline: 150+ mg/l is considered hard
321mg/l CaCO₃
UK Average: 197.72 mg/l CaCO₃Well Above Average
LowAverageHigh
pH Level
UK Standard: 6.5 – 9.5
7.1pH units
UK Average: 7.43 pH unitsWell Below Average
LowAverageHigh
Free Chlorine
Guideline: below 1 mg/l
0.58mg/l
UK Average: 0.45 mg/lAbove Average
LowAverageHigh
Nitrate
UK Standard: max 50 mg/l
27mg/l
UK Average: 16.9 mg/lWell Above Average
LowAverageHigh
Lead
UK Standard: max 10 µg/l
1.1µg/l
UK Average: 1.08 µg/lWell Above Average
LowAverageHigh
Fluoride
UK Standard: max 1.5 mg/l
0.11mg/l
UK Average: 0.19 mg/lAverage
LowAverageHigh
Water Hardness in Epsom
Hardness is the most searched water quality metric. It affects limescale buildup in kettles, boilers, and pipes.
321mg/l CaCO₃Very Hard
Soft
Mod. Soft
Slightly Hard
Mod. Hard
Hard
Very Hard
Epsom has hard water at 321 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
- Thames Water
- Supply Zone
- Epsom North (SLW34)
- Source Type
- River
- Treatment Works
- Epsom North Treatment Works
- Last Tested
- 2025-12-31
- Data Source
- Thames Water
Frequently Asked Questions
Is the water hard in Epsom?▾
Yes, Epsom has hard water at 321 mg/l CaCO₃. This is classified as "Very Hard" on the standard scale. You may notice limescale buildup in kettles and on taps.
Is Epsom tap water safe to drink?▾
Yes, tap water in Epsom is safe to drink. It is treated and tested by Thames Water and meets all UK Drinking Water Inspectorate standards. All tested parameters are within regulatory limits.
What is the water hardness in Epsom?▾
The water hardness in Epsom is 321 mg/l CaCO₃, which is classified as "Very Hard". This is above the UK national average of 170 mg/l.
Who supplies water to Epsom?▾
Water in Epsom is supplied by Thames Water, which serves the London and Thames Valley region. The water comes from river sources and is treated at Epsom North Treatment Works.