Thames Water has disputed claims there are "alarmingly high" levels of E.coli in the River Thames ahead of the Henley Regatta next week.

Campaign group River Action claimed that water quality testing done by them "revealed alarmingly high levels of E.coli bacteria from sewage pollution along the River Thames" ahead of next week’s event.

It was also announced yesterday that a person in England died amid an ongoing E.coli outbreak.

River Action said its regular testing on the Thames started on May 23 and continues until July 7, the last day of the Regatta.

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According to the group, it used a Fluidion World Health Organization verified E.coli analyser, and results analysed by Earthwatch, and the tests revealed levels of E.coli up to 25,000 CFU (colony forming units) per 100ml.

Henley Royal Regatta is a rowing event held annually on the River Thames

The group claim that this is "more than 27 times higher than what the Environment Agency grades designated bathing waters as poor".

CEO of River Action James Wallace said: "The river pollution is most likely the fault of Thames Water. 

"On behalf of rowers and Thames communities, we demand that they stop this deluge of raw sewage, which threatens river users with serious sickness and the river's biodiversity.

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"This is a health emergency."

However, Thames Water has disputed this claim, adding that its Sewage Treatment Works in the area have not released untreated wastewater since May 14.

A spokesman for Thames Water said: “We have been conducting testing for E.coli and intestinal enterococci in the river Thames in Henley since mid May, using specialist contractors to collect samples every other day, at two sites on the river, which are then tested and analysed in our ISO accredited laboratory.  

“What these laboratory tested results show so far is that E.coli levels in the Henley stretch of the Thames are consistently achieving levels the Environment Agency would deem as ‘Good’ for bathing waters, during dry conditions. 

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“There have been two days in May and two days in June where there were spikes in the readings following rainfall.

"Notably, our Sewage Treatment Works in the area have not released untreated effluent since 14 May, demonstrating that multiple sources are likely to have contributed to these elevated readings, which could include farming, industry, road runoff and wildlife.

“We have published all the results on our website, so the public can see the data and use it to make an informed choice about how they use the river. We’ve also shared all our results with the local rowing and swimming groups.

"River Action should take the same transparent approach and publish all their results for the days they tested, instead of only sharing selective days that support their chosen narrative.

“We need honest and balanced debate that recognise the range of factors impacting river health, rather than an alarmist approach that tries to apportion blame in a misguided way.”

As part of its ongoing commitment to ensure the safety and well-being of participants of the Henley Royal Regatta, the event organisers have issued the latest ‘guidance on rowing when water quality is poor’ to all rowers entering the competition.