Regulators' first joint water report says Dŵr Cymru still requires improvement

Natural Resources Wales (NRW), the Drinking Water Inspectorate, the Environment Agency and Ofwat published their first Water Industry Performance Insights report on 29 October 2026, finding that Dŵr Cymru Welsh Water "continues to require improvement" and saw an increase in serious pollution incidents.

NRW said Hafren Dyfrdwy continued to perform strongly across a number of measures, with no serious pollution incidents recorded. Dŵr Cymru Welsh Water made progress in some areas, including improved storm overflow monitoring, it said.

Ceri Davies, Chief Executive of Natural Resources Wales, said: "Improving water quality is one of the most significant environmental challenges we face. This joint insights report provides a clearer picture of water company performance by bringing together evidence from across the regulatory systems."

The four regulators said they had combined their evidence for the first time in a coordinated approach. The report uses data for the 2025 calendar year and the financial year ending March 2026, and covers 11 water and sewerage companies and six water-only companies in England and Wales.

The Welsh companies

According to the joint report, Dŵr Cymru Welsh Water serves more than 3.1 million people and has about £6bn of investment to deliver between 2025 and 2030.

NRW said its 2025 environmental performance and storm overflow spill data reports for Wales show progress alongside ongoing challenges.

The wider picture

Across England and Wales, the regulators recorded 2,991 pollution incidents in 2025, 84 of them serious. They said 93.7% of required environmental improvement actions were completed on time, with 142 of 2,254 planned actions not delivered, and that internal sewer flooding had fallen by 43% in recent years.

The report found 99.97% of drinking water tests met the required standards, and household consumption was 137.3 litres per person per day, similar to the previous year.

Philip Duffy, Chief Executive at the Environment Agency, said: "Today's report shows good performance on drinking water quality, but on wastewater and pollution the sector is still falling short."

In Ofwat's categorisation for 2025-26, ten companies are rated good or on-track and seven off-track, according to the Environment Agency's GOV.UK announcement. The Environment Agency's star ratings for English water and sewerage companies fell to 16 out of a possible 36.

Background

In its October 2025 assessment of 2024 data, NRW recorded 155 sewerage and water supply pollution incidents for Dŵr Cymru Welsh Water, including six serious incidents, and said the company self-reported 74% of incidents against NRW's 80% target. NRW said at the time that Hafren Dyfrdwy had recorded no serious pollution incidents since it was formed in 2018, and that new legislation would require water companies to publish Pollution Incident Reduction Plans by April 2026.

Hafren Dyfrdwy said in October 2025 it had achieved 100% compliance with numeric discharge permit conditions for the second year running in 2024.

What happens next

NRW said the joint report sits alongside the regulators' individual annual performance reports, with the Environment Agency, NRW and Ofwat publishing theirs on 29 October and the Drinking Water Inspectorate having published in July. Where performance falls short, NRW said, regulators will act using fines, enforcement action and requirements for companies to fix problems.

Water companies have committed more than £104bn of investment for 2025 to 2030 to upgrade water and sewage networks, the regulators said.