Newbury Water Hardness & Quality Report (2026)

Newbury, the West Berkshire market town on the River Kennet in the North Wessex Downs, is supplied by Thames Water from the River Kennet catchment and the North Wessex Downs Chalk Aquifer. The River Kennet is one of England's finest chalk streams, rising from chalk springs in the Marlborough Downs of Wiltshire and flowing east through Hungerford to Newbury, carrying dissolved chalk calcium from the Cretaceous Chalk of the Berkshire Downs and Marlborough Downs. Thames Water abstracts from the Kennet at Newbury and from chalk boreholes in the Hampstead Norreys and Berkshire chalk country. The Kennet chalk stream is moderately hard rather than extremely hard, as the upper chalk is relatively thin here compared to the deeper chalk of east Berkshire and Surrey, producing a moderately hard supply for the West Berkshire supply zone.

Newbury's hardness of 158 mg/L (11.1°Clark) reflects the River Kennet chalk stream and North Wessex Downs Chalk Aquifer in Thames Water's West Berkshire supply zone. The Drinking Water Inspectorate (DWI) classifies this supply as moderately hard.

Limescale is a regular household concern in Newbury. At 158 mg/L, limescale forms gradually in kettles and descaling every one to two months is typically advisable. Combi-boiler heat exchangers accumulate moderate deposits; annual servicing is sensible. Showerheads and taps develop light regular deposits. Washing-up liquid lathers moderately. A monthly Calgon tablet in the washing machine and a regular kettle descale is adequate limescale management for most Newbury households on the Thames Water chalk stream supply.