Water quality testing by campaigners has revealed levels of harmful E. coli bacteria up to 27 times the acceptable limit for bathing, prompting warnings for rowers to take precautions.
Very high levels of E. coli have been found at Henley, just days before elite rowers are set to compete in the international regatta there.
Testing in the Henley Mile, part of the regatta course outside the Oxfordshire town, showed mean levels of 1,213 E. coli colony-forming units (CFU) per 100ml of water, across 27 tests. Water quality is deemed poor when E. coli levels exceed 900 CFU/100ml, posing a threat to public health.
The highest reading recorded by campaigners from River Action reached 25,000 CFU/100ml, more than 27 times the acceptable limit for bathing water. The second highest reading was 8,001 CFU/100ml of water.
As a result, Henley Royal Regatta organizers are advising the 4,000 elite rowers to take precautions to avoid sickness and infection. Rowers are being advised to cover cuts and avoid swallowing splashes of river water.
As thousands of rowers prepare to compete at Henley from 2-7 July, Sir Steve Redgrave, a former Olympic rower and chair of the Henley Royal Regatta committee of management, emphasized the impact of sewage pollution on UK rivers.
“Henley Royal Regatta supports the research undertaken by River Action, which highlights the essential work that needs to be done to improve the cleanliness of our waterways for all to enjoy,” Redgrave said. “Our rowers train daily all around the country. Our waterways are vitally important to our competitors racing, but also to all those athletes training on a daily basis nationwide.”
However, Thames Water denied responsibility for the increase in bacteria and accused River Action of being alarmist. The company claimed its own testing since May at two different spots in the river yielded “reassuring” results.
Thames Water said its laboratory tests showed that apart from two days in May and two in June, E. coli levels were consistently at rates deemed good for bathing waters. The company attributed the increases to industrial and road runoff and parasites from livestock and birds, rather than its outflows.
In a tense exchange between the company and campaigners, Dave Wallace, who conducted the River Action testing in Henley, argued that Thames Water had tested different areas of the river.
Wallace used a Fluidion World Health Organization-verified E. coli analyzer – a handheld microbiological laboratory – for his testing, overseen by the NGO Earthwatch. This equipment provides results within hours, avoiding delays associated with static lab-based testing.
“We have been testing the river in an area of the highest recreational use on the Henley Mile, as it is on the regatta course,” Wallace said. “We also know that the outflow of the Henley sewage treatment works impacts this area, so we were surprised that Thames Water had decided to test at the two locks, which are long distances from the regatta course, hence low usage and lower sewage impact.”
River Action’s testing on the Henley Mile at Fawley Meadows began on 28 May and will run until 7 July. Between 28 May and 25 June, 47% of readings were above 900 CFU/100ml.
James Wallace, the chief executive of River Action, said: “It is shocking that we have had to issue health advice to the competitors of the Henley Royal Regatta. Thank goodness the organizers are showing a duty of care to the rowers by issuing guidance that will help to keep competitors safe.”
