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Revealed: Untreated sewage is being dumped into our rivers thousands of times a year. Who’s to blame and can it be stopped?

Bristol and the Climate Crisis

The surge in popularity of wild swimming during the pandemic has highlighted the extent to which our outdated sewage system dumps waste into rivers – including the Avon. The Cable asks why, and speaks to local campaigners pushing for change.

Illustration: Andy Carter

Just a week before reports of illness began flooding the Facebook page of Warleigh Weir, a popular wild swimming spot near Bath, untreated sewage was being dumped into the River Avon upstream. One mother told the Cable how, following a trip to the weir, she was woken by her son being violently sick in the middle of the night. Utility company Wessex Water has found itself in hot water with local campaigners and wild swimmers over its management of the region’s sewage system. But faced with a legacy of Victorian-era infrastructure and a failing regulatory system, can the tide be turned on this environmental and public health issue?

“At midnight we were woken by the sound of my son being very sick,” Carly White tells the Bristol Cable. “His body was literally clearing him out. I was really worried because he couldn’t even keep water down.” 

Earlier that day, she had taken her son – who has Down’s Syndrome and loves to swim – to Warleigh Weir near Bath after it became a lifeline for her during lockdown. She wasn’t the only parent left regretting that decision.

It was late August when Johnny Palmer, who owns the weir, posted on Facebook about “loads” of wild swimmers falling ill. He said this “correlated with [water supply and sewerage company] Wessex Water’s pumping of raw sewage” into the river. Swimmers from other spots alongside the River Avon have also reported sickness, including at Conham, Bitton, Batheaston and Keynsham. 

It’s not confirmed what caused the sickness. But what is known is that rivers are often dumping grounds for untreated sewage. Just the week before, a storm overflow located 4km upstream from Warleigh Weir had started releasing raw sewage into the Avon. Data shows this storm overflow dumped sewage into the river at Monkton Combe 67 times last year. But it’s not the only one. 

Over 200 storm overflows are located upstream of the weir. In total, Wessex Water released sewage into the natural environment more than 14,000 times – equivalent to 107,731 hours – between 1 January and 31 August 2021, according to data obtained by the Cable

These storm overflows have seen water companies come in for intense criticism for alleged impact on the environment and, increasingly, humans as wild swimming became massively popular during the harsh months of the pandemic.  

But behind the furore is a complicated story. 

The problem with storm overflows

In most parts of the UK, rainwater combines with sewage from homes and industry into one pipe. This system is a relic of Victorian infrastructure entirely unsuitable for modern populations, meaning that during heavy rainfall the pipes are at risk of being overwhelmed, with sewage threatening to back up into people’s homes and out of their toilets. Storm overflows operate as a release valve, dumping straight into watercourses. 

The Environment Agency (EA) provides permits to water companies to discharge sewage into rivers during exceptional rainfall events. However, a loophole in the permits means that the word “exceptional” is not defined. This means sewage is being released more frequently than it is meant to, potentially up to 10 times more than the EA estimates.

Wessex Water, which manages these overflows, denies these spills would have caused the wild swimmers to fall ill, instead blaming other factors such as agricultural run-off and wildlife. But others disagree, such as Dr Andrew Singer, a senior scientist at the UK Centre for Ecology and Hydrology, who has said the pollution impact of discharge is a risk to ecological and human health.

A recent report by the RSPB has also found sewage pollution has been contributing to the breakdown of river food chains and the death of freshwater fish en masse. The Avon has especially a lot to lose, being a designated Special Area of Conservation with a number of protected species. 

Campaigners like Johnny Palmer are asking why a company like Wessex Water cannot seem to tackle this problem, despite taking home £68m in profit in 2020/21. The company is led by Merchant Venturer Colin Skellet, and owned by YTL, the Malaysian multinational behind the controversial arena project at Filton. 

“The problem, in simple terms, is that Wessex Water is being paid to deal with an issue, which is sewage, and to process it so it can be disposed of safely,” he says. “They’re not doing that.” Palmer thinks the UK needs some serious regulatory change, but that water companies would lobby hard against that. 

Up shit creek without £150bn?

According to Matt Wheeldon, the director of asset strategy and compliance at Wessex Water, things are not so simple. 

Wheeldon challenges the premise of what critics are saying. Though storm overflows have attracted a lot of attention, he tells the Cable their environmental impact is overstated, pointing to official data that shows their operation accounts for just 3% of the reasons why water bodies do not meet environmental standards. 

The Rivers Trust has reported that overall, water companies contributed towards more than half of river water bodies failing to achieve good status. This is mainly due to the discharge of inadequately treated sewage, which includes but is not limited to storm overflows. It is a big enough problem that Wheeldon chairs a subgroup of the UK government’s Storm Overflows Taskforce, which was set up last August to deal with the pollution. 

Wheeldon says sewage discharge from overflows is “very much a societal issue” but that “water companies end up in the firing line” and that individuals need to consider their own responsibilities and expectations. “I swim at Warleigh Weir and I’ve never got ill,” he says. “I’ve never drunk the river. People saying they got ill, well, it’s a flipping river, it’s not a tap!”

The “societal” nature of the problem becomes apparent when you consider the huge scale of fundamentally changing the sewer infrastructure, with recent official estimates ranging from £67bn to £500bn to eliminate storm overflows across England and Wales. 

“It would cost around £10bn to eliminate overflows in our region,” Wheeldon says of the local picture. He adds that costs would be passed onto customers’ bills, leading to a potential 50% increase over 10 years. 

For their part, campaigners point to research showing the billions in profits siphoned off by water company shareholders rather than being directed towards investment in modern infrastructure

Wessex Water, rated one of the better companies, claims it is focusing on improving storm overflows, or at least making them less damaging, with the company planning to invest £150m in the infrastructure between 2020-2025. Wheeldon is also calling on the government to give companies powers to change the pipe infrastructure at the main source of the issue – the combining of sewage and rainwater at people’s homes – and improving drainage. 

But for that to happen, the government needs to take action. 

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‘Political desire to keep water bills down’

“River pollution is at a crisis point, and the government is clearly failing to address this,” says Kerry McCarthy, Labour MP for Bristol East, who has previously spoken out about this issue. “The Environment Bill [currently going through Parliament] does contain some provisions to help reduce sewage discharges into rivers and will require progress reports and data collection on water pollution from the government and water companies.” 

But backsliding is possible. The EA has recently given the green light for water companies to dump even more sewage due to Brexit-related chemical shortages, a move which McCarthy says she finds “deeply concerning”. 

Wessex Water says it has “no intention of taking up” the new relaxed rules, and is on track to monitor all its storm overflows by 2023, ahead of a nationwide deadline earmarked for 2030 in the updated Environment Bill

A big problem, McCarthy says, is that “the government has refused to incorporate amendments to set long-term legally enforceable targets on water quality”. Because to uphold these standards, already seen as too weak by some, official regulators need to be resourced and empowered to sanction companies that don’t comply. 

In September 2021, an official complaint lodged to the newly formed Office for Environmental Protection addressed exactly this. Wild fish campaigners at Salmon and Trout Conservation say there has been an “unhealthy conspiracy of silence” that is “driven by the political desire to keep water bills down”, resulting in policies and enforcement practises that have led to endemic underinvestment in sewage infrastructure. Predictably, the government doesn’t agree. 

In late October, Conservative MPs, including Filton’s Jack Lopresti, rejected an amendment to the Environment Bill added by the Lords which would place a duty on water companies to reduce raw sewage discharges into rivers. Following a major backlash, the government made a partial u-turn but campaigners warn the the devil will be in the detail.

Fighting for clean water downstream

But while the murky back and forth continues in Westminster, in Bristol local environmentalists are pushing for change in other ways. 

Following the success of Ilkley Clean River Group in achieving the UK’s only designated river-bathing site on the River Wharfe in Yorkshire, campaigners at Warleigh Weir and Conham River Park in Bristol are now also trying to gain designated bathing water status. 

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If achieved, this status means that the EA is required to test the water quality at these specific swimming locations throughout the bathing season of May to September, with the local council then informing the public about water quality.

The EA would also have to investigate any river pollution, but whether this would actually lead to local action in Bristol is less clear. The causes may be varied, with recent EA data finding that while pollution from all sewage accounts for 36% of damage to UK rivers, run-off from agriculture accounts for even more, at 40%. 

“I don’t want to come out and say it’s just water companies doing this,” says Becca Blease, coordinator of the Conham Bathing Water Group. But recent tests by the group have found that at their worst E coli levels were over 20 times the level considered “sufficient” for swimming by the World Health Organisation (WHO), and also showed E coli levels were much worse following heavy rain. Wessex Water has been supporting the tests, and is developing tools to enable near real-time bacteriological monitoring – and an app to inform swimmers when it is “lower risk” to swim.

Fundamental change is clearly a while off, and polluters like Wessex Water need to step up further. But Blease believes better data collection can at least provide a much clearer idea of what real solutions might look like. In the meantime, Blease will keep swimming, mouth firmly closed. “I don’t think our rivers are a lost cause,” she says.

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Report a comment. Comments are moderated according to our Comment Policy.

  • A useful article, however it would be even more powerful if you reported on the tax status of water companies, how much profit has gone offshore since taken over by private companies, dividends swollen How water & utilities companies are being dumped with debt also to make them seem less profitable. How profits could & should have been used over years to tackle underinvestment in newer systems.
    It would be good to hear Bristol MPs, such as Kerry quoted here, asked by Cable about re nationalising water & utilities. This was voted as Official Policy again at LP conf 2021 & popular w public.


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