UK Water Quality Report • 2026 Data

Water Hardness in ST21

Water supply analysis across 1 postcode sectors in ST21 (Severn Trent Water).

Outcode Avg Hardness160 PPMModerately Hard Water
Regional Quality Overview

Water Supply Analysis: Outcode ST21

Looking for water hardness metrics in ST21? Water supplied by Severn Trent Water in this outcode registers a baseline average of 160 PPM across 1 distinct postcode sectors.

Water chemistry can fluctuate across supply zones in ST21. The lowest mineral concentration is recorded in sector ST21 6 at 160 PPM, whereas sector ST21 6 experiences higher mineral levels reaching 160 PPM.

Due to the moderately hard water (160 PPM) in ST21, 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 H02) 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 ST21

Lowest mineral concentration

Softest
Sector ST21 6218 Postcodes • Moderately Hard
160 PPM11.2 °Clark

Hardest Sector in ST21

Highest mineral concentration

Highest Hardness
Sector ST21 6218 Postcodes • Moderately Hard
160 PPM11.2 °Clark

All Postcode Sectors in ST21

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