UK Water Quality Report • 2026 Data

Water Hardness in SP4

Water supply analysis across 7 postcode sectors in SP4 (Wessex Water).

Outcode Avg Hardness290 PPMHard Water
Regional Quality Overview

Water Supply Analysis: Outcode SP4

Looking for water hardness metrics in SP4? Water supplied by Wessex Water in this outcode registers a baseline average of 290 PPM across 7 distinct postcode sectors.

Water chemistry can fluctuate across supply zones in SP4. The lowest mineral concentration is recorded in sector SP4 0 at 290 PPM, whereas sector SP4 9 experiences higher mineral levels reaching 290 PPM.

Due to the hard water (290 PPM) in SP4, 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 SP4

Lowest mineral concentration

Softest
Sector SP4 0138 Postcodes • Hard
290 PPM20.3 °Clark

Hardest Sector in SP4

Highest mineral concentration

Highest Hardness
Sector SP4 9178 Postcodes • Hard
290 PPM20.3 °Clark

All Postcode Sectors in SP4

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