UK Water Quality Report • 2026 Data

Water Hardness in CB21

Water supply analysis across 3 postcode sectors in CB21 (Cambridge Water).

Outcode Avg Hardness315 PPMVery Hard Water
Regional Quality Overview

Water Supply Analysis: Outcode CB21

For residents and businesses in outcode CB21, understanding local water chemistry is essential for appliance longevity and limescale prevention. Our environmental data shows that CB21 averages 315 PPM in mineral content, falling into the Very Hard Water classification.

Water chemistry can fluctuate across supply zones in CB21. The lowest mineral concentration is recorded in sector CB21 4 at 315 PPM, whereas sector CB21 6 experiences higher mineral levels reaching 315 PPM.

Due to the very hard water (315 PPM) in CB21, 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 H07 (Max Salt)) 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 CB21

Lowest mineral concentration

Softest
Sector CB21 4240 Postcodes • Very Hard
315 PPM22 °Clark

Hardest Sector in CB21

Highest mineral concentration

Highest Hardness
Sector CB21 657 Postcodes • Very Hard
315 PPM22 °Clark

All Postcode Sectors in CB21

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