Westbury Water Hardness & Quality Report (2026)

South West Water supplies Westbury, Wiltshire, through its regional network covering Devon, Cornwall, Dorset, and Somerset. Water primarily comes from moorland reservoirs like Wistman's Intake and Roadford, rivers such as the River Dart, with treatment at plants including Chitteringpack and Clatworthy. Westbury falls under the Bristol Avon supply zone, blending surface water from Exmoor with minor groundwater components. The utility serves over 4 million people, maintaining compliance via the Drinking Water Inspectorate. The supply draws from the Bristol Avon catchment, encompassing Exmoor and Mendip Hills watersheds.

Surface sources originate from Carboniferous slate and granite bedrock, where rainfall runs off quickly with limited mineral contact, yielding very soft water. Groundwater portions tap into the Inferior Oolite limestone and Mercia Mudstone Group, allowing moderate calcium dissolution that adds some mineralisation. This geology creates a predominantly soft profile, with moorland peats imparting organic character and low buffering, while limestone inputs provide slight alkalinity without excessive hardness.

With moderately soft water, scale buildup is minimal, sparing kettles, irons, and washing machines from limescale. Boilers and showers see little impact, reducing cleaning needs. No softener is required; instead, occasional descaling suffices for longevity. This softness aids detergent efficiency and leaves skin feeling clean without residue. South West Water maintains pH around 7.5-8.5 for stability, with full lead compliance post-pipe replacements and copper levels well below limits. No notable PFAS exceedances reported; treatment involves coagulation, filtration, chlorination, and UV disinfection at surface plants, plus aeration for groundwater. Occasional moorland colour is managed via enhanced coagulation, ensuring consistent quality.