The Guardian reported on Sunday that a leaked report revealed that for the past ten years, the Environment Agency was aware that raw sewage from wastewater treatment works was being illegally dumped into English rivers.

Back in May, the agency’s chief executive, Sir James Bevan, had told parliament representatives that the practice had only surfaced very recently. He told the House of Commons environment, food, and rural affairs committee that “until recently, we have not had very good data about what is happening at sewage treatment works."

An inspection report for the northwest region dating back to 2012 showed that several sewage works owned by water company United Utilities were dumping raw sewage into rivers. The report further revealed that the company broke the conditions of its environmental permit as it failed to process the required amount of sewage.

In times of heavy rainfall and storms, water companies are generally permitted to release untreated sewage into rivers, lakes, and seas, but they can only do this when they are already treating a specified amount of sewage known as “flow to full treatment” (FtFT).

The report reveals that United Utilities received a £200,000 fine for breaking its conditions at the Cleator sewage works in Cumbria as it only processed 65% of the required sewage and the remaining was dumped into the nearby river.

Another 35 United Utilities works were suspected by the agency of dumping sewage while failing to meet the required amount of treated sewage. Some of the issues detected at nine Utilities Work had to do with FtFT at five different works as a result of problems with flow meters and an Archimedes screw, along with “erratic readings” and “gaps in flow data."

In November, the Department for Environment, Food, and Rural Affairs (Defra) announced that a number of water companies confessed that “many of their sewage treatment works may not be compliant." It was later announced that Ofwat and the Environment Agency launched a series of investigations into sewage dumping.

This announcement was delivered shortly after Windrush Against Sewage Pollution (Wasp) campaigners disseminated the results of a study that showed many works were dumping raw sewage in dry conditions and treating sewage in insufficient amounts.

Bevan had told Defra MPs that this initiative came out of the Environment Agency’s insistence that water companies keep a watch on their sewage treatment works. This was thought of as a means to incite water companies to come forward about the non-compliance of their data.

“And it was that understanding, which only came to us, frankly, within the last 12 months, that led to the investigation that the Environment Agency is running … that appears to show significant and widespread breaches of … permits,” Bevan told the MPs.

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One individual who worked on behalf of the Environment Agency admitted the report “highlights how common” the practice of dumping sewage is.

“This was known in 2012 when self-regulation was pushed and water quality monitoring, staffing and regulation was dramatically cut,” they added. “The agency had an opportunity to prevent over 10 years of illegal sewage dumping but chose not to take it, despite the funding being available. They knowingly permitted the illegal activity to continue.”

A spokesperson for the agency said the initiative “significantly driven up monitoring and transparency from water companies in recent years. In 2016, there were only 800 event duration monitors on storm overflows, and now there are more than 12,000. This data is allowing us to hold the industry to account on a scale never seen before."

Prof Peter Hammond, formerly visiting scientist at the UK Centre for Ecology and Hydrology, said that the event duration monitoring data hasn't been so reliable and that the government’s recently published plan to reduce sewage spills “relies on self-reporting of sewage spills by the water industry."

“Close scrutiny of submissions to the Environment Agency suggests water companies cannot be trusted to provide complete and correct spill data”, he said, adding that “the plan will fail unless the Environment Agency takes back control of all monitoring and dramatically improves its regulation."

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According to an Environment Agency spokesperson, a recent request for detailed data has been filed with more than 2,200 wastewater treatment works “as part of the biggest investigation we have ever undertaken into potential permit breaches – and where there is evidence of non-compliance we will not hesitate to pursue the water companies concerned and take appropriate action."

“We continue to take tens of thousands of water quality samples ourselves every year as part of our work to keep rivers clean, and we are also investing more this year to further advance our approach to sampling – and we have placed a wide range of new requirements on water companies to significantly increase their monitoring and reporting so that this data is available to all.”

A United Utilities representative said, “We pleaded guilty to five spills at Cleator wastewater treatment works a decade ago and were fined. Since then, we have had a clear plan to tackle these issues which has seen us invest millions of pounds installing more than 2,000 monitors and this has been an important factor in us achieving the top four-star environmental rating five times in the last seven years.”

Ash Smith, the founder of Wasp, said the water industry had “based its business success on ‘sweating the assets’ – not upgrading sewage works and dumping the sewage that it can’t treat into our rivers and seas, largely without interference from the Environment Agency."

He added that “the industry has become reliant on this often illegal activity to make profits and bonuses and to do this it needed the agency to let most of it go unpunished and unchecked.”

Data from the Environment Agency reveals that water companies reported dumping raw sewage into rivers and seas 372,544 times last year, for 2.6m hours - a figure, although high, is believed to be underreported.

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