Waterlooville Water Hardness & Quality Report (2026)

Waterlooville, the town in south Hampshire in the Borough of Havant on the South Downs dip slope north of Portsmouth, is supplied by Portsmouth Water from the South Downs Chalk Aquifer. Portsmouth Water operates licensed borehole abstractions at Portsdown Hill — the chalk ridge immediately south of Waterlooville — and at abstraction sites across the east Hampshire chalk downs, including Havant Thicket and Farlington. These boreholes access the Cretaceous Upper Chalk of the South Downs, which constitutes Portsmouth Water's exclusive groundwater supply for the Portsmouth–Havant–Waterlooville area. Water is treated at Portsmouth Water's Hampshire facilities before distribution to Waterlooville and the north Portsmouth zone.

Waterlooville's hardness of 219.5 mg/L (15.4°Clark) reflects the South Downs Chalk Aquifer beneath the Portsdown Hill ridge. The chalk at Portsdown Hill is a Cretaceous Upper Chalk anticline — the east-west ridge visible north of Portsmouth is the surface expression of this chalk fold — and groundwater in this chalk dissolves high calcium concentrations over its residence time in the aquifer. The hardness is somewhat lower than Gosport (254.5 mg/L) due to a blending effect from multiple chalk abstraction sites and distribution network dilution. The Drinking Water Inspectorate (DWI) classifies this supply as hard.

Limescale is a regular household challenge in Waterlooville. At 219.5 mg/L, limescale forms in kettles within two to three weeks and monthly descaling is advisable. Combi-boiler heat exchangers accumulate deposits steadily — annual boiler servicing and fitting an in-line scale inhibitor are recommended. Showerheads, taps, and shower screens develop consistent deposits. Washing-up liquid lathers moderately poorly. Using Calgon monthly in the washing machine and maintaining a regular descaling routine is important limescale management for Waterlooville households on Portsmouth Water's chalk supply.