London vs Cardiff
Water quality comparison
According to TapWater.uk, London scores 8.3/10 and Cardiff scores 9.5/10 for drinking water quality. Cardiff has the better water.
LondonThames Water · very hard water8.3 out of 10 · 79 flagged across 58 areasCardiffDŵr Cymru Welsh Water9.5 out of 10 · 0 flagged across 9 areas
Cardiff has better water quality, by 1.2 points.
Key differences
- Safety scoreCardiff scores 1.2 points higher than London.
- Contaminants flaggedLondon has 79 issues flagged vs 0 in Cardiff.
- Water supplierLondon is supplied by Thames Water, while Cardiff uses Dŵr Cymru Welsh Water.
Top concerns by city
London
- Nitrite57 areas
- Coliform Bacteria15 areas
- E. coli4 areas
- Lead2 areas
Cardiff
No contaminants flagged
Full city reports
London water reportCardiff water report
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More comparisons
London vs ManchesterLondon vs BirminghamLondon vs LeedsLondon vs GlasgowLondon vs Edinburgh
Based on water quality data from 67 postcode districts across London and Cardiff. See our methodology for how scores are calculated.