Furzedown Water Hardness & Quality Report (2026)

Thames Water supplies Furzedown, a quiet residential district in the London Borough of Wandsworth in south London between Tooting and Streatham, via the Thames Water south London ring main drawing from the River Thames treated at Hampton and Walton-on-Thames works. At 270 mg/L (18.9°Clark) and a TDS of 716.5 mg/L, Furzedown's water is very hard, driven by the chalk-dominated Thames catchment supply that defines water quality across all Thames Water distribution zones throughout south London.

The River Thames at Hampton and Walton arrives carrying dissolved calcium bicarbonate from the Chiltern Chalk and North Downs Chalk catchments. In the south London distribution network, Furzedown receives a high chalk mineral fraction via the Wandsworth ring main, with a TDS of 716.5 mg/L placing it among the harder south London zones — harder than Earlsfield (TDS 465.6 mg/L) despite geographic proximity, reflecting the specific blend routing in the Thames Water south London distribution infrastructure that delivers more mineralised supply fractions to different sub-zones of the Wandsworth network.

At 270 mg/L, limescale is a significant and relentless household challenge in Furzedown. Kettles require descaling fortnightly to prevent rapid element damage and chalky deposits in hot drinks. The combi-boiler needs a properly fitted scale inhibitor and annual professional servicing to protect the heat exchanger. Washing-up liquid requires considerably more product per wash to achieve adequate lather. Taps, shower heads, and basin mixers develop heavy limescale deposits within one to two weeks; a fortnightly descaling wipe with white vinegar or a proprietary product is strongly advisable, and a whole-house water softener is strongly recommended to protect all appliances and plumbing in this very hard chalk Thames supply zone.