Blackley Water Hardness & Quality Report (2026)

United Utilities supplies Blackley, the north Manchester suburb in the City of Manchester between Moston and Middleton — a working-class north Manchester community with close-knit terraced streets, a local shopping centre, and a tradition of heavy industry at the Blackley chemical works (the former ICI Blackley dye and chemical plant that was a major north Manchester employer from the Victorian era) — from Pennine upland reservoirs blended with Permo-Triassic Sherwood Sandstone groundwater in the north Manchester distribution zone, treated at Buckton Vale Water Treatment Works near Mossley. At 125.5 mg/L (8.8°Clark), Blackley's water is slightly hard — reflecting a proportion of Triassic Sandstone groundwater blended with the soft Pennine reservoir supply in the north Manchester distribution network.

Blackley lies in the north Manchester urban plain where United Utilities delivers supply from Pennine upland reservoirs (soft Millstone Grit catchment) blended with Permo-Triassic Sherwood Sandstone groundwater in the north Manchester sub-zone. The Triassic Sandstone fraction elevates hardness to 125.5 mg/L with TDS 320 mg/L — slightly hard water with a moderate TDS/hardness ratio (2.55) consistent with the United Utilities north Manchester distribution zone at Moston and Collyhurst in the same supply corridor.

At 125.5 mg/L, limescale is a moderate and manageable domestic concern in Blackley. Descaling the kettle every six to eight weeks is typically adequate. The combi-boiler benefits from a standard scale inhibitor as a precaution. Washing-up liquid lathers adequately at everyday quantities. Taps and shower heads develop moderate deposits over several weeks; a monthly wipe with white vinegar keeps fixtures in good condition. Blackley's slightly hard supply is characteristic of the north Manchester urban fringe — soft Pennine moorland water gaining modest calcium from the Triassic Sandstone plain that underlies the industrial north Manchester basin.