Raw sewage released into Thames around Oxford triples since 2018

A pair of paddle boarders travel along the River Thames near Donnington Bridge, Oxford (PA)
A pair of paddle boarders travel along the River Thames near Donnington Bridge, Oxford (PA)

Oxford’s rivers are being polluted with raw sewage three times more than in 2018 because Thames Water’s treatment infrastructure is “chronically under-funded”, a report claims.

An analysis of data from on spills from sewage treatment works (STWs) surrounding the city by the Oxford Rivers Improvement Campaign (Oric) revealed they discharged untreated sewage into rivers 58 times on average and for a total of 821 hours in 2020, up from 42 spills and 599 hours in 2019 and 19 spills and 193 hours in 2018.

Water companies are allowed to release untreated water containing raw sewage into rivers as a last resort after heavy rain.

But Oric, which assessed data from the Environment Agency, Thames Water and the National Rivers Trust, claims operator Thames Water is using Stormwater Discharge Consent Permits as a way to “legitimise its unacceptable performance”.

The report states: “It is quite clear from our analysis that far from being a last resort, untreated sewage is being released into the Thames and its tributaries, every week if not every day, on an entirely routine basis.

“The level of pollution is already at totally unacceptable levels and increasing at an alarming rate.

“In theory, a permit is required before such discharges are allowed. The sheer scale of spillages which are occurring indicates that either permits are being granted on an entirely casual basis or else many of the discharges are illegal, but little or no enforcement action follows.

“Either way, the current regulatory system is not working. Prosecution remains relatively rare. We suspect this is partly due to a lack of resources at the EA.

It adds: “Thames Water’s wastewater infrastructure has been chronically under-funded for many years, resulting in the capacity of STWs being inadequate for the populations they serve; a problem which will only be exacerbated by climate change and future housing development.”

A Thames Water spokesperson said: “We’ve received the report and will be looking at it carefully in the coming days.

“We regard all discharges of untreated sewage as unacceptable and will work with the government, Ofwat and the Environment Agency to accelerate work to stop them being necessary.

“We have an unprecedented amount of investment directed towards safeguarding our rivers and streams. Between 2020 and 2025 we are spending £1.25 billion on maintaining and improving our operational sites, including contributing to the health of 745km of rivers across London and the Thames Valley.”

An Environment Agency spokesperson said: “Storm overflows must only be used under strict permitted conditions that control their environmental impact.

“There has been no relaxation of storm overflow permits, which set out the specific sewage flow rates that storm overflows must meet before any discharge to the environment can take place. It is an offence if an overflow occurs and this flow rate is not met.

“We will always take enforcement action, including for illegal storm overflow discharges, where appropriate to hold those responsible for environmental harm to account. Water companies were handed record fines last year, making clear that polluters will be made to pay for damage to the environment.”