Water quality, hardness and compliance in Yorkshire
According to TapWater.uk's analysis, Yorkshire Water scores 9.4/10 for drinking water quality across 11 monitored postcode districts in 2026. The company reports 99.94% compliance with UK drinking water standards, and the average hardness across its monitored districts is 119 mg/L CaCO₃.
Scores sorted by lowest first — worst quality at the top.
Measured per district; 18% of monitored districts read hard or very hard, averaging 119 mg/L CaCO₃.
Hard water is safe to drink but drives limescale in kettles, boilers, and appliances. Check your exact postcode or read our water softener guide if scale is a daily battle in your home.
Reported compliance with UK drinking water standards.
99.94%
Compliance above 99.9% is the norm across the UK industry, which is why a compliance figure alone says little about how your water actually tastes, scales, or reads locally. The per-district scores and flagged contaminants above are where Yorkshire Water's supply differs from the national picture.
All postcode districts within Yorkshire Water's supply network.
Yes. Across 11 monitored postcode districts, Yorkshire Water's average water quality score is 9.4/10. The lowest-scoring district we monitor is YO10 (8.7/10) and the highest is S11 (9.6/10).
Across 11 monitored districts in Yorkshire Water's area, the average hardness is 119 mg/L CaCO₃ and 18% of districts read hard or very hard. Limescale pressure is moderate to low for most of this supply area.
Yorkshire Water reported a 99.94% compliance rate against UK drinking water standards. Compliance above 99.9% is the industry norm, which is exactly why we also publish per-district environmental scores and flagged contaminant counts: legal compliance and local water character are different questions.
Yorkshire Water supplies 5 million customers across Yorkshire. The postcode districts we monitor in its area: LS1, LS2, LS3, LS6, LS7, S1, S2, S10, S11, YO1 and 1 more.
Active incidents affecting Yorkshire Water appear at the top of this page as soon as our monitoring picks them up, alongside the affected postcodes. For supply emergencies always check Yorkshire Water's own website, which carries the operational updates.