Bacteria linked to faeces found at most England river bathing sites

England’s push to promote river bathing collided with a far grimmer reality: 12 of 14 inland sites tested for faecal contamination were rated poor, and people were told not to swim. Only the River Stour in Suffolk and the River Thames in Oxfordshire recorded acceptable levels.

The results sharpen the central contradiction in England’s bathing-water regime. Rivers are being designated for public use even as the Environment Agency says they are harder to keep clean than coastal waters, because they are more exposed to sewage discharges and agricultural run-off. The agency tests for E. coli and intestinal Enterococci, bacteria used as indicators of human and animal faeces, and issues the familiar ratings of Excellent, Good, Sufficient or Poor.

That tension is likely to grow this summer. The government announced six new river bathing sites will be monitored for the first time, including the first location on the River Thames in London. The move came as 13 new bathing sites opened across England on Friday 15 May 2026, taking the total to more than 460 bathing waters. The official bathing season runs from May to the end of September.

The Environment Agency said it will carry out about 7,000 to 7,500 tests across bathing waters this season, with weekly sampling at each designated site. That monitoring matters because designating a river as a bathing water creates a public expectation that the water is suitable for swimming, even when poor ratings and warning signs tell a different story. Water UK has warned that designating a site before it is clean enough can confuse the public about whether it is safe to enter.

Officials point to broader improvements elsewhere in the system. The Department for Environment, Food & Rural Affairs said 90% of respondents supported the new designations in consultation, while the Environment Agency said 417 bathing waters met the minimum standard in 2025, the highest number since the standards were introduced in 2015. It also said 87.3% of England’s bathing waters were rated good or excellent last year. But the river results show how uneven that progress remains, and how much the burden still falls on monitoring, sewage control and public warnings rather than on clean water itself.