Ewell Water Hardness & Quality Report (2026)

South East Water supplies the residents of Ewell, a town in Surrey, with water drawn primarily from groundwater. This supply originates from the Chalk aquifer, located within the North Downs region of South East England. Water is abstracted through boreholes and then treated at facilities near Dorking and Leatherhead. These treatment works employ processes such as aeration, filtration, and disinfection to ensure the water meets safety standards before it reaches homes. The utility manages this crucial resource sustainably under licenses granted by the Environment Agency, serving a vast customer base across several counties.

The geological makeup of Ewell's water supply is dominated by the Chalk aquifer, a significant groundwater reservoir formed from Upper Cretaceous Chalk rock. This limestone bedrock is highly porous and permeable, often exhibiting karstic features that facilitate the deep percolation of rainwater. As water seeps through the rock, it dissolves calcium carbonate, a process that naturally mineralises the groundwater. While overlying clay layers like the Gault Formation can influence the water's journey, the underlying Chalk geology is the primary reason for the supply being moderately mineralised rather than soft, with naturally elevated calcium levels.

Homeowners in areas with moderately hard water like Ewell might observe some scale accumulation in appliances such as kettles, boilers, and showerheads. You may also find that soaps and detergents don't lather quite as readily. Over time, dishwashers can sometimes leave spots on glassware, and washing machines might result in clothes feeling a bit stiff. Regular descaling of appliances using solutions like vinegar can help manage buildup. For those seeking to improve appliance efficiency and reduce scale, installing a water softener is an option worth considering, although it's not strictly necessary for everyone.