Revealed: Data tool shows extent of sewage spills at popular Bristol swimming spot – and it’s grim

Wessex Water has released untreated sewage into the River Avon near Conham River Park for more than 200 hours already this year, according to a new data tool.
Since May 2022, nearly 34 days of spills were recorded near the popular woodland and swimming spot just a few kilometres east of Bristol city centre, with a spike over the winter months, according to the data compiled by a campaign group.
Meanwhile, company accounts show that top bosses at the utility company, which is owned by the Malaysian multinational YTL, pocketed over £200,000 in bonuses last year for meeting a company target to protect the environment.
The Conham Bathing group’s data tool, published today, is one of the first data tools in the UK to monitor sewage spills as they happen, helping wild swimmers to decide whether or not to brave the water despite spills of untreated sewage.
The live dashboard published by the group’s campaign organiser Becca Blease, who the Cable interviewed last year about the rights of rivers, follows in the footsteps of other community groups, such as Surfers Against Sewage, who have created trackers in recent years.

“I’m really glad we’ve been able to provide this tool. I’m excited about it,” Blease says. “But it’s also sad that it’s taken a group of volunteers to put this together. I think Wessex Water should have been doing this. If they’re spilling sewage into our waters, they should be informing us about when this is happening,” she says.
In 2021, a Cable investigation revealed that Wessex Water spilled untreated sewage into the environment for more than 107,000 hours between January and August that year alone. E. Coli levels at Conham were up to 20 times the level deemed “sufficient” for swimming, according to World Health Organization standards.
This prompted backlash from local campaigners and political figures, including Kerry McCarthy MP who cited the Cable’s findings to Defra officials at a parliamentary debate.
But Blease says not enough has changed since then, motivating her and others to start taking action themselves.
Last summer, they applied for designated bathing water status, which would have required the Environment Agency to monitor bacteria levels. However, Bristol City Council blocked their application, citing local bylaws that prohibit swimming in the harbour and Avon.
A petition was launched in response, quickly gaining more than 5,000 signatures, followed by a lively protest outside City Hall, but Mayor Marvin Rees stood his ground. “He decided not to support the amendment to the bylaw,” Blease says, adding that it will be a couple of years before this is reviewed again.
Wessex Water told the Cable it supports the desire to make more use of rivers for recreation, including swimming, and has been working with the Conham Bathing group and others to increase awareness of water quality and promote safer access for recreation.
Turning the tide
Now, the Conham Bathing group has created an online tool that converts email alerts sent directly from Wessex Water into infographics, showing data about sewage spills at four sites – one each in Saltford and Hanham and two in Keynsham.
“Local swimmers have been aware of this issue for years, but we haven’t had much evidence about how frequently these storm overflows are being used,” Blease says.
Storm overflows act as a release valve to ensure sewers are not overwhelmed during periods of exceptional rainfall. However, the regulatory system has been criticised as being weak, with water companies potentially spilling up to 10 times more sewage than the Environment Agency estimated.
Meanwhile Thérèse Coffey, the environment secretary, announced last month that she will be giving water companies an extra 27 years to end sewage spills.
“We don’t have another 27 years to fix the problem,” Emma Nicol says, who has worked tirelessly on the campaign at Conham. “This decision is not bold enough and further demonstrates this government’s inability to take the climate and biodiversity crisis seriously.”
In response to a request for comment, Wessex Water said that storm overflows, which are licensed by the Environment Agency, operate automatically during or after intense rainfall to prevent flooding of properties and that they release mostly rainwater.
“We agree that storm overflows aren’t fit for the 21st century,” a spokesperson said. “We’re spending £3 million per month on improving them and reducing how often they operate.”
Upstream from Conham, most spills have occurred at one particular overflow in Keynsham, which has released sewage into the Avon for the equivalent of 25 days over the last nine months.

The new tool only monitors four out of nearly 1,300 storm overflows across Wessex Water’s entire catchment, so Blease admits that broader environmental and human health impacts are hard to establish.
The Cable has previously revealed how wild swimmers became violently sick after untreated sewage was released upstream of Warleigh Weir near Bath, although the cause was not officially confirmed.
“At midnight we were woken by the sound of my son being very sick,” one mother told the Cable, after her son had swam at the weir in summer 2021. “His body was literally clearing him out. I was really worried because he couldn’t even keep water down.”
Other swimmers from Bitton, Batheaston and Keynsham also reported feeling unwell.
Wessex Water says that lowland rivers will always have bacteria in them and that the safety of wild swimming at specific locations is for councils and others to determine. “But we want to help people make an informed choice,” a spokesperson told the Cable.
Eye-watering profits
Wessex Water’s environmental performance is rated according to specific regulatory targets, which can lead to significant bonuses for water company bosses. Company accounts show that Wessex Water took home £43m in profit last year.
Last year, Colin Skellet, the company’s CEO, was paid bonuses of £190,000 in total, with £60,000 of this sum paid out for meeting a specific target to protect the environment.
In total, the company’s top directors were paid over £650,000 in bonuses last year, £220,000 of which was as a reward for “protecting and enhancing the environment”, despite “serious pollution incidents” increasing to the highest level since 2013.
Wessex Water is now classed as “requiring improvement” by the Environment Agency.
In response to the Cable’s findings, Wessex Water said that it is “very disappointed” about the EA’s results, having been “an industry leader for environmental performance for so long”. The company’s spokesperson added that the majority of polluting incidents in 2021 were caused by sewer blockages.
With regard to executive bonuses, Wessex Water said these are set by an independent committee and that the company has been performing well against environmental targets.
“In particular, we had the fewest number of pollution incidents for 10 years and achieved 100% wastewater treatment compliance for discharges to the environment from our water recycling centres – the only company to achieve this,” the spokesperson said.
New solutions
Some campaigners do believe the company is starting to deliver concrete action. Johnny Palmer, who owns Warleigh Weir near Bath, has been running a campaign to clean up the river since he bought the land in 2017.
“Wessex Water could have so easily ignored us, and they haven’t done that,” he says. “I do respect them for actually engaging.”
“It all kicked off initially and I sat down with them and said, ‘It’s not good enough. Let’s sort it out’ – and since that conversation they’ve engaged quite positively. You will get change if you rattle some cages.”
Palmer recently announced that Wessex Water is going to install a large storage tank near the weir to reduce the number of spills at one of the main storm overflows by 85%. The project will begin this September and is forecast to cost £1.9 million.
Blease remains optimistic too, but her campaign has not finished just yet.
“I think it’s really important that our concerns about the river continue to be taken seriously,” Blease says. “We are an important part of the conversation and we have asserted ourselves as that.”
Despite the inevitable frustration of the council’s pushback and the lack of action from the government, Nicol says it’s all been worth it.
“The bright flash of a kingfisher swooping past, the trees that frame the river as you swim in the middle, the ability to access an area so peaceful, so close to the city,” she says of Conham River Park.
“I love seeing people of all ages enjoy the river in the warmer months – even before our campaign this was a well-loved site. Let’s protect it!”
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