Belmont Water Hardness & Quality Report (2026)

Affinity Water supplies Belmont, the south London suburb in the London Borough of Sutton between Cheam and Banstead — a quiet residential community on the North Downs dipslope, with a village character of mostly interwar and post-war housing, a local parade of shops, and a setting at the transition from the suburban London fringe to the Surrey chalk downland — from the North Downs Chalk (Cretaceous) aquifer boreholes in the south London Sutton supply zone, treated at Bough Beech Water Treatment Works near Edenbridge. At 202 mg/L (14.2°Clark), Belmont's water is hard — consistent with the Cretaceous Chalk aquifer of the North Downs that supplies the south London and Surrey fringe through the Affinity Water south London distribution zone.

Belmont lies on the North Downs chalk dipslope in the Affinity Water south London Sutton supply zone. Affinity Water draws from North Downs chalk boreholes in the Sutton–Cheam–Banstead corridor, producing 202 mg/L with TDS 457.4 mg/L — hard water with a low TDS/hardness ratio (2.26) confirming predominantly chalk carbonate hardness, consistent with the Affinity Water south London North Downs chalk distribution zone at Cheam (205 mg/L) and Sutton in the same supply corridor.

At 202 mg/L, limescale is a consistent household challenge in Belmont. Kettles should be descaled monthly. The combi-boiler benefits from a fitted scale inhibitor and annual professional servicing. Washing-up liquid requires more product per wash. Taps and shower heads develop visible white limescale deposits within one to two weeks; a fortnightly wipe with white vinegar or a proprietary descaling product keeps fittings clean. Belmont's hard North Downs chalk supply is characteristic of the south London–Surrey fringe — the great Cretaceous Chalk escarpment visible to the south delivering mineralised chalk groundwater to every household on the Sutton dipslope.