High Levels of E. coli Detected in River Thames at Henley Raise Health Concerns Ahead of Henley Royal Regatta

High levels of E. coli have been detected in the River Thames at Henley, where the Henley Royal Regatta will take place from July 2-7, 2024. Testing by River Action, an environmental campaign group, found E. coli levels on the Henley Mile section of the course reaching up to 27 times the acceptable limit for bathing water. The organization recorded a highest mean of 1,213 E. coli colony-forming units (CFU) per 100ml, with the peak reading at 25,000 CFU/100ml.

Henley Royal Regatta organizers have issued warnings to the 4,000 competing rowers about potential health risks, advising them to cover cuts and avoid ingesting river water. Sir Steve Redgrave, chair of the regatta committee, emphasized the importance of improving waterway cleanliness for safe competition.

Thames Water, the regional water supplier, has disputed the findings, asserting its own tests showed satisfactory water quality in the river. According to Thames Water, their tests conducted at different sites near Henley since mid-May generally found E. coli levels within safe limits, except for a few spikes linked to rainfall.

River Action focused its testing near Fawley Meadows, close to a Thames Water combined sewer overflow, which often discharges untreated sewage. Thames Water suggested multiple factors could influence elevated bacteria levels, including agricultural runoff, industrial pollution, and wildlife.

Testing by River Action and oversight by the NGO Earthwatch will continue until July 7, with nearly half of the tests by June 25 indicating poor water quality by Environment Agency standards. The regatta’s organizers, alongside British Rowing and The Rivers Trusts, have provided safety guidelines to all participants.