Inspectorate defines legal requirements for desalinated and recycled water

The Drinking Water Inspectorate (DWI) has written to water companies setting out how the Water Industry Act 1991 and the Water Supply (Water Quality) Regulations 2016 apply to desalinated and recycled water.

The letter is clear that the statutory duty to supply wholesome water under section 68 of the Act, and the requirements for wholesomeness set out under Regulation 4 of the regulations, apply should such water sources be deployed.

According to the DWI: “For both recycling and desalination schemes, securing wholesomeness will require an understanding of the nature of the source water, risk assessment and consider the use of the multi-barrier approach. This will include a need to understand any emerging contaminants that are present and consider expert opinion on drinking water safety, research and independent medical advice from UK Health Security Agency (UKHSA).”

In addition, to comply with the wholesomeness standards set out at Regulation 4, drinking water must also conform to the taste and odour standard. The DWI recommended early engagement with consumers to confront these issues, highlighting that any remineralising arrangements should be a “key consideration to consumer acceptability”.

Elsewhere the letter dealt with matters including sampling, risk assessment and mitigation, disinfection and treatment, and the products use in the manufacture of processing plant.