UK Water Quality Report • 2026 Data

Water Hardness in RH10

Water supply analysis across 10 postcode sectors in RH10 (Southern Water).

Outcode Avg Hardness277 PPMHard Water
Regional Quality Overview

Water Supply Analysis: Outcode RH10

Looking for water hardness metrics in RH10? Water supplied by Southern Water in this outcode registers a baseline average of 277 PPM across 10 distinct postcode sectors.

Water chemistry can fluctuate across supply zones in RH10. The lowest mineral concentration is recorded in sector RH10 3 at 270 PPM, whereas sector RH10 9 experiences higher mineral levels reaching 280 PPM.

Due to the hard water (277 PPM) in RH10, 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 RH10

Lowest mineral concentration

Softest
Sector RH10 3375 Postcodes • Hard
270 PPM18.9 °Clark

Hardest Sector in RH10

Highest mineral concentration

Highest Hardness
Sector RH10 9122 Postcodes • Hard
280 PPM19.6 °Clark

All Postcode Sectors in RH10

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