UK Water Quality Report • 2026 Data

Water Hardness in KT12

Water supply analysis across 6 postcode sectors in KT12 (Affinity Water).

Outcode Avg Hardness290 PPMHard Water
Regional Quality Overview

Water Supply Analysis: Outcode KT12

Analyzing water quality disclosures across all 6 postcode sectors in outcode KT12 reveals an average water hardness of 290 PPM (Hard Water). Public water supply across this area is managed by Affinity Water, responsible for treating and delivering water to residential households.

Water chemistry can fluctuate across supply zones in KT12. The lowest mineral concentration is recorded in sector KT12 1 at 290 PPM, whereas sector KT12 9 experiences higher mineral levels reaching 290 PPM.

Due to the hard water (290 PPM) in KT12, 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 KT12

Lowest mineral concentration

Softest
Sector KT12 1194 Postcodes • Hard
290 PPM20.3 °Clark

Hardest Sector in KT12

Highest mineral concentration

Highest Hardness
Sector KT12 912 Postcodes • Hard
290 PPM20.3 °Clark

All Postcode Sectors in KT12

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