Stephen Eades – Identifying and prosecuting the water companies for illegal storm sewage discharges – Sep 25

Last year in 2024 the recorded number of ‘storm sewage overflows’ made in England into our rivers and seas by the water companies was 450,398. In terms of simple averages, that works out at 1,234 storm discharges every day.

Of course, averages are misleading because storm discharges are meant to happen only on days when it rains heavily, causing sewage works to become overloaded. So on dry days, according to the environmental permits issued by the Environment Agency to sewage works, there should, in theory, be no ‘storm discharges’ at all. That’s zero discharges on dry days. Is that the case?

The answer to this question has been elusive. The presumption has been that the large annual total, for example 450,398 in 2024, has been due to genuine rain induced discharges, albeit occurring in excess at some outfalls above the guideline limit of 20 per year and, in a small number of cases, at over 60 times or more per year. Although clearly polluting, these rain induced overflows have not been ‘illegal’ under the sewage works’ environmental permits and, as a result, this high level of pollution persists, and no prosecutions follow.

However, environmental permits do not allow ‘storm discharges’ to be made on dry days, and so these types of discharge are illegal. Therefore, in the annual figure of 450,398, is there a percentage that is being made on dry days?

Until now, there has been no answer to that question. In August of this year The Times newspaper reported that it had made a Freedom of Information request to the Environment Agency that asked: how many dry day overflows were made in January and February of 2025 and which water companies were making them? The table below summarises the Agency’s reply. It is based on an article published by East Devon Watch.

English water company dry day discharges of untreated sewage, January and February 2025.

Source: Data supplied by Environment Agency to The Times newspaper, published August 2025 and reproduced here from online article by East Devon Watch.

Clearly, dry day storm discharges are happening throughout England and all of the water companies are implicated. In fact, if the January and February figure is projected for the year as a whole, there will be around 37,062 dry day discharges which, using the 2024 figures, means that around 8% of all discharges are being made on dry days. That is approaching one in every ten discharges occurring on a dry day.It also illustrates that the capacity of many sewage works in England is seriously undersized. They simply cannot handle the sewage that is arriving on a dry day, let alone on a wet day. Given this reality, it is hardly surprising that the number of storm discharges in England is so great.The question is: will the water companies be prosecuted, and made to clean-up their act?