UK Water Quality Report • 2026 Data

Water Hardness in KT11

Water supply analysis across 4 postcode sectors in KT11 (Affinity Water).

Outcode Avg Hardness267.5 PPMHard Water
Regional Quality Overview

Water Supply Analysis: Outcode KT11

Looking for water hardness metrics in KT11? Water supplied by Affinity Water in this outcode registers a baseline average of 267.5 PPM across 4 distinct postcode sectors.

Water chemistry can fluctuate across supply zones in KT11. The lowest mineral concentration is recorded in sector KT11 2 at 260 PPM, whereas sector KT11 1 experiences higher mineral levels reaching 290 PPM.

Due to the hard water (267.5 PPM) in KT11, limescale build-up can occur on heating elements, shower heads, and boilers. Setting your dishwasher water softener to the correct level (e.g. Bosch setting H04) is strongly recommended to prevent cloudy glassware and internal scale accumulation. Review the individual postcode sectors below to get precise dishwasher salt settings and limescale recommendations.

Softest Sector in KT11

Lowest mineral concentration

Softest
Sector KT11 2235 Postcodes • Hard
260 PPM18.2 °Clark

Hardest Sector in KT11

Highest mineral concentration

Highest Hardness
Sector KT11 1147 Postcodes • Hard
290 PPM20.3 °Clark

All Postcode Sectors in KT11

Select a postcode sector below to view exact water softener salt settings, limescale protection guides, and appliance recommendations.