Skip to main content
💧 TapWaterData

How hard is Yorkshire Water's water, zone by zone?

Yorkshire Water's sampled supply-zone record runs 47.9–370.6 mg/L as CaCO₃, varying by supply zone, which spans DWI's Soft to Very hard bands, per Yorkshire Water — supply-zone water quality reports returned by its own postcode checker (31 December 2024, read 20 September 2026).

Source: Yorkshire Water — supply-zone water quality reports returned by its own postcode checker — dated 31 December 2024, read 20 September 2026

Drinking Water Inspectorate (DWI) enforces the UK drinking water quality regulations in England and Wales. Figures it classifies or regulates on this page cover England and Wales only.

What this record covers

Every row below is a total hardness figure for one area Yorkshire Water supplies, read one answer at a time from the publisher's own checker rather than from a published list. 4 supply zones from 6 postcode lookups of the company's own checker — a bounded sample, not a published list.

This supply’s total hardness, in every unit used here

UnitThis supply
mg/L as CaCO₃47.9–370.6 mg/L as CaCO₃
°Clark3.4–26 °Clark

This supply runs 47.9–370.6 mg/L as CaCO₃, varying by supply zone. That spans DWI’s Soft (up to 100) to Very hard (more than 300) bands, so no single band describes it.

Every total hardness figure in this record

Where these numbers come from

47.9–370.6 mg/L as CaCO₃ across 4 areas, published by Yorkshire Water.

Source: Yorkshire Water — supply-zone water quality reports returned by its own postcode checker — dated 31 December 2024, read 20 September 2026

More on hard water here

By TapWaterData Editorial