Environmental group Action for the River Kennet has issued a pollution warning after the recent bad weather.

The river is still on flood alert and ARK has warned that when ground water levels are high, sewers can become so full that the lids pop up, letting sewage flow directly into the river.

The group is asking people to report pollution from sewers to the Environment Agency and to Thames Water as well as telling ARK where problem areas are. Although Thames Water deals with flooding from its sewers, ARK would like to see sewers maintained to a standard where sewer flooding is much less frequent.

Charlotte Hitchmough, ARK’s director, said: “We are meeting Thames Water this month and one of the issues we will be discussing is the performance of their sewers and sewage treatment works during wet weather. It is unacceptable that raw sewage enters the river each time we get heavy rain.”

The group is also encouraging residents to help reduce sewer flooding by being careful what they flush away, avoiding things such as wet wipes and cooking fat.

The warning has been endorsed by the Angling Trust which campaigns for clean rivers.

Mark Owen, head of freshwater at the trust, said: “It is vital that the water companies are funded by the regulator to build in greater resilience to extreme weather conditions because the current ageing infrastructure is not up to coping with what climate change is throwing our way.”

Contact the Environment Agency's incident line on 0800 807060, Thames Water on 0845 9200 800 and contact ARK by emailing carolyn@riverkennet.org