Bayswater Water Hardness & Quality Report (2026)

Thames Water supplies Bayswater in the Royal Borough of Kensington and Chelsea and City of Westminster, central London. Supply is drawn from the River Thames abstracted at Kempton and Hampton, treated at Kempton Water Treatment Works near Twickenham, distributed via the central London ring main beneath the city. At 308.5 mg/L (21.6°Clark) and a TDS of 891.5 mg/L, Bayswater's water is very hard — typical of central and west London where the combined chalk-dominated Thames catchment and the treatment blend from Hampton–Kempton produces near-1000 mg/L TDS hard water.

The River Thames at Hampton arrives having drained the Chiltern Chalk and the North Downs Chalk catchments, carrying sustained dissolved calcium bicarbonate from chalk springs and aquifer discharge throughout the middle Thames. Kempton Water Treatment Works processes this chalk-river abstraction and delivers it via the west and central London distribution network. The very high TDS of 891.5 mg/L — approaching the extreme values seen in the deepest confined chalk boreholes — reflects the cumulative chalk mineral loading of the Thames at the Hampton abstraction point, where centuries of chalk-spring inputs have concentrated dissolved calcium.

Limescale is an intense and relentless daily challenge in Bayswater. Kettles must be descaled every one to two weeks to prevent rapid element failure and calcium particles in drinks. Combi-boilers face a very high risk of premature breakdown without a properly fitted, annually replaced scale inhibitor and regular professional servicing of the heat exchanger. Washing-up liquid requires substantially more product per wash to produce adequate lather. Taps, shower screens, and basin mixers must be descaled weekly to prevent permanent hard-water staining, and a whole-house water softener is strongly recommended to protect all appliances, plumbing, and the boiler from severe limescale damage in this hard water central London supply zone.