Dŵr Cymru Welsh Water supplies Cardiff from reservoirs in the Brecon Beacons and Taff Fawr valley.
According to TapWater.uk's analysis, Cardiff scores 9.5/10 for drinking water quality in 2026. Water is supplied by Dŵr Cymru Welsh Water and has been tested for 23 contaminants across 9 postcode districts.
Average score
9.5/10
UK avg: 9.0/10
Areas tested
9
Issues flagged
0
PFAS detected
None
Yes, Cardiff tap water is safe to drink. Based on 9 areas tested, Cardiff has an average water quality score of 9.5/10 (above the UK average of 9.0/10). No contaminants were found above recommended levels. Water is supplied by Dŵr Cymru Welsh Water. Dŵr Cymru Welsh Water supplies Cardiff from reservoirs in the Brecon Beacons and Taff Fawr valley.
All postcode districts in Cardiff, ranked by water quality score.
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Yes, Cardiff tap water is generally safe to drink. Across 9 areas tested, the average water quality score is 9.5/10. Dŵr Cymru Welsh Water supplies Cardiff from reservoirs in the Brecon Beacons and Taff Fawr valley.
Yes, you can drink tap water in Cardiff. It is regulated to UK drinking water standards, and across 9 tested areas the average water quality score is 9.5/10. Enter your postcode for the readings in your exact area.
No contaminants were flagged above recommended levels across Cardiff. All tested areas passed on the parameters measured.
Hardness data is not yet available for Cardiff. Enter your postcode for detailed water quality data.
The areas with the best water quality in Cardiff are CF30 (10.0/10), CF10 (9.4/10), CF11 (9.4/10).
Water in Cardiff is supplied by Dŵr Cymru Welsh Water. Dŵr Cymru Welsh Water supplies Cardiff from reservoirs in the Brecon Beacons and Taff Fawr valley.
No PFAS (forever chemicals) have been detected in any of the 9 areas tested in Cardiff.
Free live water quality widget for CF30: paste these two lines anywhere on your page. It stays up to date by itself and credits TapWater.uk automatically.
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<script src="https://www.tapwater.uk/widget.js" async></script>Get a detailed water quality report for your exact area in Cardiff.