UK Water Quality Report • 2026 Data

Water Hardness in CT21

Water supply analysis across 4 postcode sectors in CT21 (Affinity Water).

Outcode Avg Hardness290 PPMHard Water
Regional Quality Overview

Water Supply Analysis: Outcode CT21

For residents and businesses in outcode CT21, understanding local water chemistry is essential for appliance longevity and limescale prevention. Our environmental data shows that CT21 averages 290 PPM in mineral content, falling into the Hard Water classification.

Water chemistry can fluctuate across supply zones in CT21. The lowest mineral concentration is recorded in sector CT21 4 at 290 PPM, whereas sector CT21 9 experiences higher mineral levels reaching 290 PPM.

Due to the hard water (290 PPM) in CT21, 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 CT21

Lowest mineral concentration

Softest
Sector CT21 4195 Postcodes • Hard
290 PPM20.3 °Clark

Hardest Sector in CT21

Highest mineral concentration

Highest Hardness
Sector CT21 96 Postcodes • Hard
290 PPM20.3 °Clark

All Postcode Sectors in CT21

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