Seaford Water Hardness & Quality Report (2026)

South East Water serves the town of Seaford and surrounding areas in East Sussex, supplying water to over two million customers across Kent, Sussex, and parts of Surrey. The utility's primary water source is groundwater, drawn from boreholes that tap into the Chalk aquifer located beneath the South Downs National Park. While the Pevensey Levels and Arlington Reservoir offer supplementary surface storage, the supply heavily relies on these underground reserves, with no major rivers directly feeding the system. Treatment takes place at local facilities, including the Seaford Water Treatment Works, where processes like filtration, chlorination, and fluoridation are employed to meet the stringent standards set by the Drinking Water Inspectorate.

The water originates from the Cretaceous Chalk group, a geological formation characterized by its porous, limestone-rich bedrock. As rainwater infiltrates this karstic terrain within the South Downs catchment, it dissolves significant amounts of calcium and magnesium ions. This natural process, occurring in the Upper Chalk formation, imparts a characteristically hard mineral content to the groundwater. The extensive, permeable nature of the aquifer ensures consistent water yields, but the water's composition consistently reflects the calcium-rich bedrock of this region.

Homeowners in Seaford will likely notice the effects of this very hard water, particularly in the form of limescale buildup. This mineral deposit can reduce the efficiency and lifespan of appliances like kettles, boilers, and showerheads, while also impacting pipework. Dishwashers and washing machines may require more detergent to achieve the same cleaning results, and fabrics can feel stiffer. To combat scale, regular cleaning with household solutions like vinegar or citric acid is recommended. For comprehensive protection against scaling throughout the home, installing a water softener is strongly advised. South East Water monitors and manages water quality, with treated groundwater typically showing a pH between 7.5 and 8.5.