Serious water pollution remains high despite £5bn investment, regulators say

Serious pollution from water companies in England remained at similarly high levels in 2025, despite £5bn of investment over the previous five years, according to a new joint report from the sector’s regulators.

Eight of the nine companies in England were rated either “poor” or “requiring improvement” for environmental performance. Severn Trent was the only company to receive the highest rating. The industry’s combined environmental score was 16 out of a possible 36 stars, its worst on record, the Environment Agency said.

The report is the first joint assessment by the Environment Agency, Natural Resources Wales, Ofwat and the Drinking Water Inspectorate. It found that companies had reduced service disruptions, but said serious pollution remained a “major concern”. In Wales, Dŵr Cymru Welsh Water received two stars out of four from Natural Resources Wales.

Environment Agency chair Alan Lovell said the results exposed “the scale of underperformance across the sector”. He said some companies had not delivered environmental improvement schemes for which they had received funding. The agency also said the overall score reflected both declining performance in some areas and tighter standards.

Companies have pledged record investment through to 2030 to upgrade networks and sewage treatment works. Water bills are expected to rise by an average of 36% as a result, according to the BBC.

Environment Secretary Dame Angela Eagle said she was “demanding answers from the companies that are failing”. Water UK, the industry body, acknowledged that some companies’ environmental performance was “not good enough”, while pointing to improvements in leakage. It said the investment would take time to deliver cleaner rivers and seas.