UK Water Quality Report • 2026 Data

Water Hardness in GY4

Water supply analysis across 1 postcode sectors in GY4 (Guernsey Water).

Outcode Avg Hardness140 PPMModerately Hard Water
Regional Quality Overview

Water Supply Analysis: Outcode GY4

Looking for water hardness metrics in GY4? Water supplied by Guernsey Water in this outcode registers a baseline average of 140 PPM across 1 distinct postcode sectors.

Water chemistry can fluctuate across supply zones in GY4. The lowest mineral concentration is recorded in sector GY4 6 at 140 PPM, whereas sector GY4 6 experiences higher mineral levels reaching 140 PPM.

Due to the moderately hard water (140 PPM) in GY4, 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 H01) 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 GY4

Lowest mineral concentration

Softest
Sector GY4 6253 Postcodes • Slightly Hard
140 PPM9.8 °Clark

Hardest Sector in GY4

Highest mineral concentration

Highest Hardness
Sector GY4 6253 Postcodes • Slightly Hard
140 PPM9.8 °Clark

All Postcode Sectors in GY4

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