Water quality, hardness and compliance in North West
According to TapWater.uk's analysis, United Utilities scores 9.4/10 for drinking water quality across 13 monitored postcode districts in 2026. The company reports 99.97% compliance with UK drinking water standards, and the average hardness across its monitored districts is 44 mg/L CaCO₃.
Scores sorted by lowest first — worst quality at the top.
| Postcode | Area | Score | Status |
|---|---|---|---|
| L1 | Liverpool | 9.3/10 | Excellent |
| L2 | Liverpool | 9.3/10 | Excellent |
| L8 | Liverpool | 9.3/10 | Excellent |
| M1 | Manchester | 9.4/10 | Excellent |
| M2 | Manchester | 9.4/10 | Excellent |
| M3 | Salford | 9.4/10 | Excellent |
| M14 | Manchester | 9.4/10 | Excellent |
| M20 | Manchester | 9.4/10 | Excellent |
| M21 | Manchester | 9.4/10 | Excellent |
| L3 | Liverpool | 9.4/10 | Excellent |
| L5 | Liverpool | 9.4/10 | Excellent |
| M4 | Manchester | 9.5/10 | Excellent |
| M5 | Salford | 9.5/10 | Excellent |
Measured per district; 0% of monitored districts read hard or very hard, averaging 44 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.
99.97%
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 United Utilities's supply differs from the national picture.
All postcode districts within United Utilities's supply network.
Yes. Across 13 monitored postcode districts, United Utilities's average water quality score is 9.4/10. The lowest-scoring district we monitor is L1 (9.3/10) and the highest is M5 (9.5/10).
Across 13 monitored districts in United Utilities's area, the average hardness is 44 mg/L CaCO₃ and 0% of districts read hard or very hard. Limescale pressure is moderate to low for most of this supply area.
United Utilities reported a 99.97% 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.
United Utilities supplies 7 million customers across North West. The postcode districts we monitor in its area: M1, M2, M3, M4, M5, M14, M20, M21, L1, L2 and 3 more.
Active incidents affecting United Utilities appear at the top of this page as soon as our monitoring picks them up, alongside the affected postcodes. For supply emergencies always check United Utilities's own website, which carries the operational updates.