Water quality along the stretch of the River Thames which will host the iconic Oxford v Cambridge Boat Race has been classified as poor by clean water campaigners, as a result of E coli from sewage pollution.

Testing carried out along the four-mile route, which the university rowing teams will tackle on Sunday, has revealed E coli levels which are three times above the threshold for poor bathing water status.

When a site is classified as “poor”, the Environment Agency advises against bathing due to the risk to human health.