Drinking water quality
Welsh Water supplies drinking water to over 3 million customers in over 1.4 million homes and business across England and Wales.
Supplying wholesome drinking water, 24 hours a day, 365 days a year is our highest priority. This means that our tap water remains free from harmful chemicals and bacteria while maintaining a pleasant taste.
Every year, over 300,000 samples are taken from our water treatment works, service reservoirs and customers' properties. Every day, water samples are taken throughout our supply system and analysed at our laboratories which are equipped with state-of-the-art instrumentation.
The water we supply must meet the standards set out in the Water Supply (Water Quality) Regulations 2018. If you’d like to find out more about all the parameters we monitor for, take a look at our Water Quality Zone Reports on our In Your Area site.
More Information
Help & advice
Strange taste or smell to my water
Occasionally customers report that their water doesn’t taste or smell as it usually does.
Help & advice
Water appearance
Information to help you identify what could be causing appearance problems, reasons why it is happening and what you can do to help resolve it is available here.
Help & advice
Water hardness
The information here gives a summary of what water hardness is, and how to find the water hardness in your area.
Help & advice
Water quality in the home
Here you can find useful information on some common household water quality queries such as slime and staining, fishkeeping advice, and lead pipes.
Water Supply
Information Sheets
Browse our leaflets around your water supply, including information on fluoride, iron, maganese and lead.
Check your water hardness and quality
Enter your postcode or find your area and check the top left corner of the map for your water quality.
Information about water quality
Discoloured water is usually caused by the disturbance of deposits in the water pipes. The disturbance of deposits can happen when a water main is shut off due to essential maintenance or in an emergency.
Discoloured water is unlikely to be harmful to health and often resolves within a few minutes once you run your taps, but it might need up to 45 minutes to clear completely.
With our In Your Area service, you can find out if there is any planned or emergency work near you that could affect your water supply.