Water Hardness and Quality in Old Knebworth
Supplied by Affinity Water · Knebworth/Tewin (AF015)
Old Knebworth has hard water with quality that meets all UK drinking water standards.
Check a specific postcode in Old Knebworth
Water Quality Scorecard
Total Hardness
Guideline: 150+ mg/l is considered hard
295mg/l CaCO₃
UK Average: 197.72 mg/l CaCO₃Well Above Average
LowAverageHigh
pH Level
UK Standard: 6.5 – 9.5
7.5pH units
UK Average: 7.43 pH unitsAbove Average
LowAverageHigh
Free Chlorine
Guideline: below 1 mg/l
0.37mg/l
UK Average: 0.45 mg/lBelow Average
LowAverageHigh
Nitrate
UK Standard: max 50 mg/l
26.7mg/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
0.225mg/l
UK Average: 0.19 mg/lWell Above Average
LowAverageHigh
Water Hardness in Old Knebworth
Hardness is the most searched water quality metric. It affects limescale buildup in kettles, boilers, and pipes.
295mg/l CaCO₃Hard
Soft
Mod. Soft
Slightly Hard
Mod. Hard
Hard
Very Hard
Old Knebworth has hard water at 295 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
- Knebworth/Tewin (AF015)
- Source Type
- Groundwater
- Treatment Works
- Knebworth/Tewin Treatment Works
- Last Tested
- 2025-12-31
- Data Source
- Affinity Water
Frequently Asked Questions
Is the water hard in Old Knebworth?▾
Yes, Old Knebworth has hard water at 295 mg/l CaCO₃. This is classified as "Hard" on the standard scale. You may notice limescale buildup in kettles and on taps.
Is Old Knebworth tap water safe to drink?▾
Yes, tap water in Old Knebworth 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 Old Knebworth?▾
The water hardness in Old Knebworth is 295 mg/l CaCO₃, which is classified as "Hard". This is above the UK national average of 170 mg/l.
Who supplies water to Old Knebworth?▾
Water in Old Knebworth is supplied by Affinity Water, which serves the South East England region. The water comes from underground aquifers and is treated at Knebworth/Tewin Treatment Works.