Longfield Water Hardness & Quality Report (2026)

South East Water supplies Longfield, a village in west Kent on the dip slope of the North Downs north of Meopham. Supply is drawn from the North Downs Chalk aquifer via deep boreholes beneath the Kent Downs chalk plateau, treated at Eccles and regional Kent works before distribution across north-west Kent. At 319 mg/L (22.4°Clark) and a TDS of 908.1 mg/L, Longfield's water is very hard — among the hardest in Kent — driven by the thick, pure Upper Cretaceous Chalk of the North Downs that underlies Longfield and the surrounding chalk downland.

The North Downs in west Kent comprise some of the thickest, most pure chalk in south-east England — a permeable aquifer extending north-east from the Surrey–Hampshire border across the Weald anticline. Groundwater infiltrating the chalk from the downland crest percolates through hundreds of metres of porous Cretaceous limestone before reaching the abstraction boreholes, accumulating extensive calcium bicarbonate through prolonged dissolution chemistry. The confined chalk beneath the lower dip slope north of Longfield concentrates dissolved minerals to near-1000 mg/L TDS levels typical of the most extreme Kent chalk supplies.

Limescale is an intense and relentless challenge in Longfield. Kettles must be descaled every one to two weeks to prevent rapid element degradation. Combi-boilers face a very high risk of premature failure without a properly fitted, annually replaced scale inhibitor and regular professional servicing of the heat exchanger. Washing-up liquid requires substantially more product per wash to produce adequate lather in this very hard water. Taps, shower screens, and basin mixers must be descaled weekly to prevent permanent hard-water staining, and a whole-house water softener is strongly recommended to protect all appliances and plumbing from severe limescale damage.