Defra cites progress in sewage pollution but charities urge caution

EH insists it will continue to hold underperforming water companies to account while Rivers Trust wants reassurance public money is being spent in "right way.”

Storm overflow spills in England were fewer and shorter in 2025, according to new monitoring data, but concerns remain over the continued scale of sewage discharges and the influence of weather conditions on the figures.

Data published by the Department for Environment, Food & Rural Affairs (Defra) and the Environment Agency (EA) shows a reduction in both the number and duration of storm overflow events compared with 2024. The figures are based on Event Duration Monitoring (EDM), now in place across the vast majority of overflows in England.

The government said the results indicate progress, while acknowledging that further improvements are needed. 

Emma Hardy, Water Minister, said, “It is good to see that storm overflow spills are down since the previous year, but there is still an unacceptable amount of sewage entering our waterways and a long way to go in cleaning up our rivers, lakes and seas.”

The EA emphasised the role of both investment and external factors such as rainfall in shaping annual results. Alan Lovell, Chair, EA said: “Publishing this data each year ensures the public can see clearly what is happening across England’s storm overflows. 

“While these numbers are heavily influenced by rainfall levels in 2025, substantial reductions in spill duration and events are a clear win for people and the environment. 

“It is vital that improvements to the sewage system are sustained over the long term, and the Environment Agency will continue to hold water companies to account where performance falls short.” 

Environmental organisations analysing the same dataset have highlighted the need for caution in interpreting year-on-year changes. 

Surfers Against Sewage (SAS) said that while the figure is lower than the previous year, it’s not evidence of a system improving, but a reflection of unusually dry weather. Giles Bristow, Chief Executive, SAS, added that three months into 2026 the water companies’ level of sewage dumping had already dwarfed last year. “This dirty business hasn’t changed a bit. The sewage scandal rages on.

“But it’s not about the figures. It’s about the scores of swimmers, surfers and children that continue to risk their health because water companies and the government choose profits over people.

“The government must take decisive action. Meet with the victims, stop pandering to polluters and take back control of the broken sector to make it work for the public good, not investor purses.”

“Nearly 300,000 [spills] is still far too many and many of these are likely to be illegal."

Separate analysis from The Rivers Trust also pointed to the impact of reduced rainfall on the 2025 figures. Michelle Walker, Technical Director, The Rivers Trust, said, “We expected to see a lower number of sewage discharges in 2025 as it was such a dry year, but this should not be mistaken for progress. Nearly 300,000 is still far too many and many of these are likely to be illegal.  

“There is a lot of public money now being spent on water infrastructure after decades of underinvestment and regulatory failure. We need to know this is being spent in the right ways to put an end to pollution and protect both people and nature.”

The Rivers Trust pointed out that, despite drier conditions “untreated sewage was still discharged into English waterways 291,492 times, for a total of over 1.8 million hours.”

Storm overflows are designed to release excess wastewater only during periods of heavy rainfall to prevent sewer systems from becoming overwhelmed.

As Walker says, in the short term “a big step forward” would be monthly or quarterly updates and reporting on delivery against the published Water Industry National Environment Programme (WINEP) showing status and completion dates of improvements. 

Walker also stressed the need for better data regarding the in-river impacts of “not just untreated sewage but also treated sewage effluent from water company assets as well as private septic tanks and package treatment works which are all increasing loading nutrients and pollutants into our rivers on a continual basis as our population grows.”