West Molesey Water Hardness & Quality Report (2026)

Thames Water supplies West Molesey in Surrey, a riverside suburb on the south bank of the River Thames between Hampton and Walton-on-Thames. Supply is drawn from the River Thames abstracted at Hampton and Walton-on-Thames, treated at Hampton Water Treatment Works and Walton Water Treatment Works, delivered via the Thames Water distribution network across north Surrey. At 209 mg/L (14.7°Clark), West Molesey's water is hard, reflecting the chalk-dominated Thames catchment geology that characterises all communities supplied from Thames abstraction in the Surrey reaches.

The River Thames above Hampton draws on chalk and limestone catchments from the Cotswolds and the Chilterns, arriving in the Surrey reach with characteristic calcium bicarbonate hardness. The North Downs Chalk aquifer immediately south of the Thames at Molesey contributes groundwater components that elevate hardness in the local distribution zone. West Molesey's position directly opposite Hampton Water Treatment Works — one of the largest treatment facilities in the Thames Water network — means its supply receives freshly treated Thames chalk-river water.

Limescale is a consistent household concern in West Molesey. Kettles should be descaled monthly to prevent element efficiency loss and chalky deposits in drinks. The combi-boiler benefits from a fitted scale inhibitor to protect the heat exchanger, and annual servicing is recommended. Washing-up liquid requires slightly more product than in softer-water areas to achieve a satisfactory lather. Taps and shower heads develop visible white limescale deposits within one to two weeks; a fortnightly wipe with white vinegar or a proprietary descaling solution is recommended to keep fittings clean and prevent hard-water staining from becoming permanent on surfaces.