Water Hardness in Harrow
Harrow has very hard water at 363 mg/l CaCO₃. This is above the UK national average of 197.72 mg/l. You may notice limescale buildup on taps, in kettles, and around showerheads.
363
mg/l CaCO₃
Very HardUK average: 197.72 mg/l
363
0 (Soft)200 (Hard)400+ (Very Hard)
What Does Very Hard Water Mean?
With a hardness of 363 mg/l, Harrow has very hard water. This level of hardness is common in areas supplied from chalk and limestone aquifers in the South East of England.
You will likely notice white limescale deposits on taps, showerheads, and inside your kettle. Over time, limescale can reduce the efficiency of boilers and heating systems, increasing energy costs. A water softener can help prevent these issues.
Water Supplier
- Water Company
- Affinity Water
- Supply Zone
- Harrow South (AF093)
- Source Type
- Groundwater
- Treatment Works
- Harrow South Treatment Works
Full Water Quality Report for Harrow
See all 8 water quality parameters including pH, chlorine, lead, nitrate, fluoride and more.
Frequently Asked Questions
Is water hard in Harrow?▾
Yes, Harrow has hard water at 363 mg/l CaCO₃, classified as "Very Hard". You will likely notice limescale buildup on taps, in kettles, and around showerheads. A water softener or regular descaling can help manage this.
What is the hardness of water in Harrow?▾
The water hardness in Harrow is 363 mg/l CaCO₃ (milligrams per litre of calcium carbonate). This is classified as "Very Hard" on the standard UK scale and is above the national average of 197.72 mg/l. Water is supplied by Affinity Water from underground aquifer sources.
Who supplies water to Harrow?▾
Water in Harrow is supplied by Affinity Water, which covers the South East England region. The water is sourced from underground aquifers (boreholes) and treated at Harrow South Treatment Works before distribution.