Water Hardness Breakdown for Sector GY1 1
Covering 346 active delivery postcodes in the GY1 district, households and businesses in sector GY1 1 are supplied with tap water averaging 140 PPM (9.8° Clark). Distributed under the regulatory oversight of Guernsey Water, local tap water supplies in this catchment are rated as slightly hard.
With a balanced reading of 140 PPM (9.8° Clark), water in GY1 1 exhibits a moderate mineral structure. While limescale accumulation is gradual, minor scale rings can form inside kettles and on boiler heat exchangers over 6–12 month periods (estimated thermal efficiency drag of 4% – 7%).
The water supply managed by Guernsey Water in this region is primarily abstracted from upland reservoirs, lakes, and moorland catchments with impermeable granite or sandstone geology. This geological pathway limits mineral leaching, maintaining a low-to-moderate hardness baseline of 140 PPM throughout GY1 1.
In everyday household use, calcium and magnesium ions in 140 PPM water bind with soaps, producing chalky bathroom residue and scum on your morning cuppa. In sector GY1 1, washing laundry or dishware requires medium detergent volume with routine machine descaling. For personal grooming, individuals with dry skin or eczema sensitivity may experience skin tightness after showers in this slightly hard water environment.
Calibrating appliance water softening systems in GY1 1 prevents etched glassware and heating element burnouts. Based on Guernsey Water's official 140 PPM rating, Bosch dishwashers should be set to H01. Consult the interactive equipment guide below for custom brand settings across all 346 postcodes.