Hurstpierpoint Water Hardness & Quality Report (2026)

Southern Water supplies Hurstpierpoint, an affluent West Sussex village between Burgess Hill and Brighton at the foot of the South Downs — a community of Georgian and Victorian architecture, the nationally renowned Hurstpierpoint College, and the Danny House (a sixteenth-century manor used in the First World War) — from South Downs Chalk boreholes in the mid-Sussex chalk belt, treated at Falmer Water Treatment Works near Brighton. At 320.5 mg/L (22.5°Clark) and a TDS of 920.2 mg/L, Hurstpierpoint's water is extremely hard — among the very hardest in West Sussex — consistent with the fully chalk-saturated South Downs Upper Chalk that supplies the mid-Sussex communities at the foot of the Downs with some of the hardest water in England.

Hurstpierpoint lies on the Low Weald clay immediately below the South Downs chalk escarpment, in the Southern Water supply zone where chalk boreholes at the base of the Downs extract deeply mineralised Upper Chalk groundwater. The freely recharged, unconfined South Downs Chalk at this location produces 320.5 mg/L with TDS 920.2 mg/L — extremely hard water that places Hurstpierpoint among the hardest supply zones in Britain, consistent with the extreme hardness throughout the mid-Sussex South Downs foothill communities from Hassocks through Hurstpierpoint to Henfield.

At 320.5 mg/L, limescale is an extreme and relentless household problem in Hurstpierpoint. Kettles must be descaled weekly to prevent rapid element failure. The combi-boiler faces very high risk of premature breakdown without a properly fitted, annually replaced scale inhibitor and regular professional servicing. Washing-up liquid requires very generous quantities for any lather. Taps, shower heads, and basin fittings develop heavy chalk encrustation within days; a weekly descaling is essential to prevent permanent blockage and staining. A whole-house water softener is very strongly recommended for all Hurstpierpoint households.