More than 100,000 sewage discharges recorded in Welsh waters

Sewage was discharged into Welsh waters more than 100,000 times last year, including over 7,000 releases without the appropriate environmental permits, according to a new report.

Surfers Against Sewage’s annual Water Quality Report recorded 101,176 discharges across Wales in 2025, lasting a combined 822,265 hours — the equivalent of almost 94 years.

Across Welsh Water’s network, 827 overflows discharged more frequently than in 2024, despite substantially drier weather across the UK.

The charity also identified 4,083 discharges affecting 90 Welsh bathing waters, lasting a combined 35,669 hours.

Wales accounted for around a fifth of recorded UK discharges and more than a quarter of their total duration, despite having about 5% of the population.

Monitoring coverage varies considerably, however. The report lists full coverage in Wales and England, compared with 30% in Scotland and 20% in Northern Ireland, meaning the UK figures understate the overall scale of discharges.

Responding to the findings, the Welsh Government said: “We’re taking full control of water in Wales, so decisions are made by Wales, for Wales.

“We’ll apply the polluter-pays principle, including prosecuting serious and persistent offenders.

“Water reform demonstrates how Wales and the UK can work together to strengthen and simplify devolution, while keeping effective cross-border cooperation.”

Its planned Welsh water regulator would take over Ofwat’s responsibilities for company charges, investment requirements and limits on executive pay and bonuses. This depends on the devolution of remaining water powers, which ministers are pursuing with the UK Government.

Natural Resources Wales would retain its separate responsibility for water quality, pollution incidents and environmental standards.

The government also highlighted Ofwat’s decision on 5 June to accept a legally binding £44.7 million package of commitments from Dŵr Cymru Welsh Water following an investigation into its wastewater treatment works and sewer networks.

Ofwat found that the company had failed to operate, maintain and upgrade its works and networks adequately to cope with sewage and wastewater flows.

Unpermitted discharges

The report combines water companies’ monitoring returns covering storm overflows, emergency overflows and outlets operating without environmental permits.

Llanfachraeth wastewater treatment works on Anglesey accounted for 366 of the unpermitted discharges. The report says the site lacked a discharge permit.

A further 3,358 releases were recorded from emergency overflows, which are intended to operate in rare, critical circumstances.

Preliminary analysis identified 27,683 Welsh Water discharges in the first six months of 2026, although those figures are based on unverified data.

Welsh Liberal Democrat MP David Chadwick described the findings as a “national embarrassment”.

Mr Chadwick, whose Brecon, Radnor and Cwm Tawe constituency includes stretches of the Wye, Usk and Tawe, said: “People should be able to enjoy our rivers, lakes and beaches without worrying about sewage pollution or putting their health at risk.

“We urgently need to see proper investment in our ageing infrastructure, stronger independent regulation and real consequences for those responsible for pollution.”

Bathing waters

Llyn Padarn had the highest number of discharges among the bathing waters listed in the report, with 247, followed by Swansea Bay with 224, Llandudno West Shore with 184, Llanfairfechan with 176 and Tywyn with 156.

All five were classified as having “good” or “excellent” bathing water quality. The figures combine releases from overflows associated with each location, which may be affected by more than one outlet.

The charity received 215 reports of sickness following water use in Wales during 2025, and another 187 between January and the end of August this year.

It argues that Welsh Water’s not-for-profit structure has not prevented pollution and calls for better-resourced environmental regulation.