As the weather warms, lockdown restrictions begin to lift, and students return to Oxford for Trinity Term, outdoor activities, including wild swimming, are on the rise. Students have been taking to the banks of Port Meadow for picnics, and some are venturing into the water of the River Thames. This idyllic summer image, however, is undermined by the alarming levels of bacteria that can be found in the water as a result of sewage dumping by Thames Water into the waterways in and around Oxford. 

A study funded by Thames Water and published by the group #EndSewagePollution found harmful levels of E. coli Bacteria present in The River Thames in Port Meadow from January to March 2021. At each of four tested locations, E. coli levels exceeded the threshold level for safe bathing water quality during three of the ten weeks. This study, amongst others, is part of a movement supported by Thames Water to turn Oxford into a designated bathing water area, allowing the already-existing population of wild swimmers to continue with their activities safely. 

Symptoms of E. coli infections include vomiting, stomach cramps, and fever. Diarrhoea is another common symptom, and around half of those infected develop bloody diarrhoea. In rare cases, an infection can lead to kidney failure. Tim Harris, an associate at the Rivers Trust, told the Oxford Mail: “We don’t know for certain whether these levels of bacteria are from raw sewage or other sources like agriculture – to know that, we need to wait for a few more months of results. However, this data indicates that, if you swam in the river this winter and swallowed some river water, you could have had an unpleasant dose of E. coli”.

A survey sent out by the Iffley Fields Residents Association Waterways group revealed in a set of results sourced in April that Port Meadow is the most popular bathing location. Participants cited “physical, mental, and spiritual rejuvenation” as the benefits they experienced through wild swimming. However, participants also cited “fear of pollution, fear of injury, and lack of access” as the major issues that are preventing people from enjoying the benefits of Oxford’s bathing sites. 

A petition on Change.org has over 5,000 signatures to give the Thames in Oxford, also known as the Isis, designated bathing water status. While the movement to achieve this status has been taken on by Oxford City Council, at the current levels of dumping, the water quality assessment for such a swimming area would still fall into the “poor” categorisation. In the meantime, various projects are in place to help swimmers make educated decisions about safety. Amongst these is a brand new alert system published by Thames Water that gives live updates on sewage discharges from six locations in and around the city. 

The alert system is currently operating via Twitter and Facebook, with updates stating “please be aware our monitoring systems at [discharge point] are indicating a discharge of diluted sewage to the river started at [time].” Recent updates have been coming in on what can sometimes be a daily basis.

The data from the 2020 Annual Thames Water Return reveals that last year, these six locations collectively produced a total of 281 spills and 3,817.62 hours of spill duration. While the levels of bacteria in the water could be in part due to local agricultural waste, it is clear that a significant amount of sewage has been contributing to the issue, as is currently allowed by law. If Oxford is to achieve designated bathing water status, the Environment Agency will create a water profile in addition to monitoring and protecting the water. This will provide the community with legal grounds upon which to fight against dumping into local rivers. 

The City Council’s bid will likely be submitted sometime before this autumn to be examined by DEFRA, the Government’s Department for the Environment, Food, and Rural Affairs, and hopefully accepted by next summer. The official DEFRA guidance on applying for such a designation requires that an application be supported by local authorities as well as including user surveys, information about any facilities at the site, and evidence of a consultation. User surveys must show a breakdown of the number of swimmers, children paddling, and other beach and water users. Local consultations must include any local groups that might be affected by the designation, including but not limited to bathers, residents of the closest town, local environmental groups, town councils, and local tourist offices. 

After an application has been submitted, DEFRA will consult the local water company, the Environment Agency, the Country Land and Business Association, the Marine Conservation Society, the Outdoor Swimming Society, Visit England, Water UK, and a number of other relevant groups. Ministers will make the final decision. 

Cherwell met with local community activist Ned Wells to discuss the movement to #EndSewagePollution. Wells is an Oxford resident, a graduate of Oxford Brookes University in Engineering, and a fly fisher. In fishing for wild trout, which are an indicator species, he realised that the Thames had poor water quality as it is not a suitable environment for the trout. When he was approached by another member of the campaign, Claire Robertson, Wells decided to help. 

Cherwell also met with Claire Robertson, a PhD student in freshwater ecology and avid year-round river swimmer. Robertson explained that one of the biggest obstacles in ending sewage pollution is the water companies’ outdated infrastructure: “Groundwater easily infiltrates into sewage pipes, meaning they rapidly overflow when there is heavy rain.”

Wells and Robertson cited four organisations as being particularly supportive of their goal: The Rivers Trust, Thames 21, Oxford City Council (specifically Councillor Linda Smith), and Thames Water. The Rivers Trust is a federated charity that has produced a GIS-based map (Geographic Information Systems). According to The Rivers Trust, this technology “helps develop an understanding of complex environmental systems, builds confidence and eases communication between a wide range of people and organisations who need to work in partnership to improve the water environment.” 

On Thames Water, Wells explained, “Although they’re the villain in this plot, they know the game is up and they know they’ve got to do something about it. There’s a charitable point of view that says that if lots of their customers are livid with them, it should be easier for them to get sign-off on the huge investment needed to make the sewage system fit for purpose.” Wells is working closely with Thames Water on the project to provide sewage alerts. Robertson elaborated, “Thames Water are providing funding for my time to work on the entire project, lab time and space for the bacterial water quality testing, and funding for equipment.”

Looking forward, Wells and Robertson say the team is feeling confident about the prospective success of the application to DEFRA, which is due to be submitted around October 2021.

The movement has truly been spearheaded by the “local community community of passionate river swimmers, paddlers, anglers, rowers, and nature enthusiasts,” Robertson explained, “the people of Oxford genuinely love their rivers, and want to see them clean, healthy, and well-protected.”

Richard Aylard, Thames Water’s sustainability director, said: “Discharges of untreated sewage are unacceptable to us, our customers and the environment, and we will work with the government, Ofwat, the Environment Agency and others to accelerate work to stop them being necessary.”

“Our business plan for the next five years includes an unprecedented amount of investment, much of it directed towards safeguarding the environment. We have a long way to go and we certainly can’t do it on our own – but the ambition is clear. Our aim will always be to try and do the right thing for our rivers and for the communities who love and value them.”

Iffley Fields Residents Association and Oxford City Council have been approached for comment.

Image Credit: AstacopsisGouldi / CC BY-SA 4.0


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