Rustington Water Hardness & Quality Report (2026)

South East Water supplies Rustington and surrounding areas in West Sussex, serving 17 postcode districts across Kent and Sussex. The utility draws primarily from groundwater boreholes tapping into the chalk aquifers beneath the South Downs. Key abstraction points include boreholes in the Arun Valley and Crawley areas. Water is treated at facilities like the Rustington Water Treatment Works, with regional plants such as the Barcombe or Bewl Bridge works used for blending if necessary. This extensive network serves approximately 2.5 million customers across coastal towns like Rustington (BN16 postcode) and the wider watershed, which encompasses the South Downs catchment draining into the English Channel via rivers like the Arun.

The water originates from thick chalk strata of the Late Cretaceous period, forming productive aquifers within the Southern Chalk Uplands. These white micritic limestones, part of the Northern and Southern Downs groups, naturally dissolve calcium-bearing minerals as rainwater percolates through. This geological process results in a characteristically hard water supply with a high mineral content. The region's geology, dominated by these karstic chalk bedrock, facilitates rapid infiltration and mineral enrichment, typical of southeastern England's groundwater.

Homeowners in this area often notice limescale buildup in appliances such as kettles, boilers, and showerheads, which can reduce their efficiency and lifespan. Hot water systems, dishwashers, and heating elements are particularly susceptible to insulating deposits that increase energy consumption. To combat these issues, regular descaling with vinegar or citric acid, cleaning taps, and lowering boiler temperatures below 60°C are helpful measures. For very hard conditions, installing a water softener is often recommended to prevent scum, extend appliance life, and improve soap lathering. South East Water maintains compliance with UK drinking water standards, with pH typically between 7.2–7.6 in treated groundwater supplies.