Ensuring the quality of your drinking water

Samples are routinely collected from our treatment works, service reservoirs and randomly selected customer properties.

Authorised Thames Water personnel who all carry identity cards collect these samples.

The safety of our customers is important to us and to ensure this, we have compiled some advice for determining a genuine Thames Water representative from a bogus caller.

Following collection, water samples are passed to our advanced laboratory for analysis.

The laboratory is independently assessed and accredited by the United Kingdom Accreditation Service (UKAS).

It employs highly trained staff with extensive analytical skills in microbiology, organic and inorganic chemistry, metals analysis and materials testing.

Every year more than 400,000 laboratory tests are performed to ensure your drinking water is of the highest quality.