Exclusive: water firms discharged raw sewage into England's rivers 200,000 times in 2019.
Untreated effluent flowed into waterways for more than 1.5m hours, data shows.
Water companies in England discharged raw sewage into rivers on more than 200,000 occasions last year, according to data obtained by the Guardian.
The analysis reveals untreated human waste was released into streams and rivers for more than 1.5m hours in 2019.
The figures, obtained via environmental information requests, trace releases of sewage from storm drains in rivers across England by all nine water companies and provide a comprehensive picture of the scale of pollution from what critics say is the routine dumping of untreated sewage.
Popular English rivers including the Thames, the Windrush, which runs through the Cotswolds and Oxfordshire, the River Chess, a chalk stream in Buckinghamshire, the Avon in Bristol, the Severn, and the River Wharfe in Ilkley are among the many affected.
The data emerges as increasing numbers of people are using England’s rivers to swim, kayak and paddleboard.
Countries are legally obliged to treat sewage before it is released into waterways. Discharges of untreated human waste are permitted only in “exceptional circumstances” for example after extreme rainfall, the European court of justice has ruled.
But the scale of the sewage releases in 2019 reveals what one industry insider said was the frequent and routine nature of discharging untreated effluent from storm overflows.
The source, who has worked in the industry for many years, said the discharges released “a horrible septic mix of nasties into the rivers”.
He said the industry had for years ignored warnings about the growing scale of spills from combined sewer overflows (CSOs) – storm pipes that allow rainwater, untreated sewage and runoff to discharge into waterways.
Recent scientific research has also raised concerns that Covid-19 can be carried into rivers via sewage discharges.
Guardian data reveals 6,508 inland CSOs released untreated sewage into rivers 204,134 times in 2019. The spills discharged for 1.53m hours across the nine English water companies.
Luke Pollard, the shadow environment secretary, said: “Sewage discharges should take place only in the most extreme of circumstances. Regulation needs to be tightened to stop water companies using discharges as a day-to-day measure.
“Customers will rightly be shocked at the frequency of sewage discharges and the damage it does to some of our country’s most precious and valuable river habitats.”
The Environment Agency issues permits to allow water companies to release untreated human waste, which includes excrement, condoms and toilet paper, from CSOs after extreme weather events, such as torrential rain, to stop water backing up and flooding homes.
More than 60 discharges a year from a storm overflow should trigger an investigation by the agency but the data reveals some storm overflows have released discharges hundreds of times. The Environment Agency relies on water companies to self-monitor their CSOs.
Ashley Smith of the campaign group Windrush against Sewage Pollution said the system was little more than a “licence to pollute”. Smith, who monitors sewage spills on the River Windrush in Oxfordshire, said discharges happened after just a rain shower.
He said: “The industry has been given a way to prop up failed infrastructure and it has exploited this enthusiastically. The inability of the Environment Agency to prosecute or even drive improvement has led us to where we are today – in a complete shambles with pollution rife and unchecked.”
Michelle Walker of the Rivers Trust described the data as “very alarming”. The environmental charity worked with the Guardian’s data to create an interactive map where you can search for river discharges by area.
She said: “When you look at the detail, you see that some of these locations are releasing untreated sewage hundreds of times a year, so they are not just operating during extreme rainstorms.”
A recent study revealed the quantity of E coli coming out of CSOs was between 1,000 and 10,000 times higher than that coming from treated sewage from wastewater treatment plants.
Walker said: “People think our rivers should be fit to swim in but they don’t realise it is legal to discharge untreated raw sewage into our rivers.”
Water companies say the spills are so diluted by rainwater and wastewater that they do not affect the quality of the water.
Wessex Water said: “As CSOs should only operate during periods of intense rainfall, any foul water released from them will be very dilute … Rarely is a pollution incident attributed to a CSO operating correctly.”
1 July 2020
The Guardian