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Water quality

We work hard to improve the quality of your drinking water.

Every year we carry out more than 500,000 tests. We take samples from our water mains and pipes, as well as from customers’ taps.

Since 2010, more than 99.95% of tests taken from customers’ taps met the standard required by UK and European legislation.

If you want to check out the water quality in your local area, all you need is your postcode.

Check your water quality

A Thames worker holding up a jar of water carrying out a water quality test

Our range of water quality topics

We go through the different types of water and how if you have lead pipes it may affect your water.

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Hard water

Our water passes through soft chalky limestone. That’s why our water is hard.

View hard water

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Different smell, taste or look

There could several reasons why your water is a different colour or taste.

View common water issues

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Lead pipes

You may have lead pipes if your property was built before 1970.

View lead pipes