UK Water Quality Report • 2026 Data

Water Hardness in SM1

Water supply analysis across 5 postcode sectors in SM1 (SES Water).

Outcode Avg Hardness260 PPMHard Water
Regional Quality Overview

Water Supply Analysis: Outcode SM1

Looking for water hardness metrics in SM1? Water supplied by SES Water in this outcode registers a baseline average of 260 PPM across 5 distinct postcode sectors.

Water chemistry can fluctuate across supply zones in SM1. The lowest mineral concentration is recorded in sector SM1 1 at 260 PPM, whereas sector SM1 9 experiences higher mineral levels reaching 260 PPM.

Due to the hard water (260 PPM) in SM1, 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 SM1

Lowest mineral concentration

Softest
Sector SM1 1108 Postcodes • Hard
260 PPM18.2 °Clark

Hardest Sector in SM1

Highest mineral concentration

Highest Hardness
Sector SM1 945 Postcodes • Hard
260 PPM18.2 °Clark

All Postcode Sectors in SM1

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