Darton Water Hardness & Quality Report (2026)

Darton, the Barnsley village on the north Barnsley fringe between Mapplewell and Cawthorne — in the former South Yorkshire coalfield north of Barnsley town centre — is supplied by Yorkshire Water from a blend of soft Pennine reservoir supply and groundwater from the Permian Magnesian Limestone belt east of Barnsley. Yorkshire Water operates boreholes in the Magnesian Limestone east of the coalfield and distributes soft upland reservoir water from the Don and Dearne valleys supply system into the Barnsley network. At 201 mg/L with TDS 575.9 mg/L (ratio 2.86), Darton's supply shows the characteristic elevated-TDS Magnesian Limestone chemistry — calcium sulphate from Zechstein dolomite and gypsum–anhydrite evaporite beds in the Permian formation raising TDS significantly above the carbonate hardness level. Darton is slightly harder than Chapeltown (166.5 mg/L, north Sheffield) and similar to Lofthouse (198.5 mg/L, east Leeds) — both in the same Magnesian Limestone supply belt running north–south through South and West Yorkshire.

The Permian Magnesian Limestone of the Barnsley and south Yorkshire belt is the Zechstein Lower Magnesian Limestone (ZL1 and ZL2) — a pale to cream dolomitic limestone with interbedded anhydrite, gypsum and minor halite beds from the original Zechstein evaporite sequence. Yorkshire Water boreholes tap this formation east of the coalfield at 50–120 m depth, producing water enriched in calcium sulphate at 180–210 mg/L. Blended with softer Pennine reservoir supply, the final Darton distribution supply reaches 201 mg/L — the moderately hard character typical of the Yorkshire Magnesian Limestone supply zone north of Doncaster.

At 201 mg/L Darton's water is moderately hard and limescale management is a regular domestic concern. Kettles benefit from monthly descaling with a citric acid tablet. Shower heads and tap aerators need periodic soaking in white vinegar. Washing-up liquid must be used in moderate amounts. Combi-boilers benefit from scale inhibitor protection. Darton's north Barnsley village character — old stone farmhouses, the colliery-era terraces of Mapplewell and the open south Yorkshire countryside — is supplied by the moderately hard Magnesian Limestone-influenced water of the Yorkshire supply belt east of the Pennine coalfield ridge.