Families taking to the water during hot weather may have been unaware that storms have overwhelmed the country’s sewage network, leading to the release of raw waste

Dangerous pollutants in England’s waterways have reached their highest levels since modern testing began, The Times can reveal, with no river in the country now certified as safe for swimmers.

Wild swimming has surged in popularity, with tens of thousands of people bathing in countryside rivers and ponds during the heatwave.

However, an investigation by this newspaper has revealed that rivers in England are not tested enough to be considered safe for swimming. Eighty-six per cent fall short of the EU’s ecological standard — the minimum threshold for a healthy waterway — up from 75 per cent a decade ago.

In addition, half of all stretches of river monitored by the Environment Agency exceeded permitted limits of at least one hazardous pollutant last year,