Secret court documents reveal potential scale of illegal sewage spilling

Image source, PA Media Image caption, Public protest against sewage spills have increased in recent years

Environment correspondent Published 23 July 2026 Most of the sewage spills into England's waterways in the last two years may have been illegal but gone unpunished, according to new analysis.

UK law states that raw sewage should not be released during "normal" weather conditions, yet until now the regulator has not clarified exactly what that means.

But campaigner Prof Peter Hammond obtained a definition in secret court papers, and said it shows that for more than 80% of the time sewage was being spilled, the weather was "normal", making the spills possibly illegal.

The water companies and the regulator, the Environment Agency (EA), rejected the analysis and said they were working to reduce spill numbers.

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Published 1 day ago The last few years have seen growing awareness and mounting public anger at the amount of raw sewage that is being discharged into England's rivers, lakes and seas.

The country's sewage issues are, in large part, caused by the fact that drains usually take rainfall into the same network of pipes that remove waste from homes.

This means that when it rains, if there is not enough spare capacity, the system and sewage treatment works can be quickly overwhelmed.

But until now, it has not been clear what amount of rainfall there must be before water companies can legally spill raw sewage into waterways. Campaigners have said this has allowed the industry to spill routinely with no consequences.

Earlier this year, a source at the EA sent Prof Hammond undisclosed documents from a court case against Southern Water for illegal sewage spilling in 2021 .

It included a previously undisclosed definition of "heavy rain" conditions. And accompanying internal EA documents confirmed that water companies can spill sewage when there is "heavy" rain i.e. beyond the "normal" weather conditions.