A damning BBC documentary has claimed tonnes of raw sewage is being dumped into the Thames.

The River Pollution Scandal by BBC Panorama focused on a number of water companies across the UK which it said were illegally dumping untreated sewage into rivers.

Thames Water's Mogden Treatment Works dumped sewage into the river 43 days last year, the programme claimed.

Homes in Isleworth were recently flooded as raw sewage spilled from the river and Thames Water pledged to carry out a proper clean-up.

Raw sewage is sent into rivers through storm overflows which can be activated when water levels are exceptionally high, usually when there is heavy rainfall.

But the programme claimed that many water companies, including Thames Water, were activating them for days on end - sending millions of litres of untreated sewage into rivers.

Thames Water responded in the programme by saying it is committed to reducing sewage in the Thames, it believes that it is unacceptable for any amounts of sewage to go into rivers, and that it is investing heavily.

The company said it had not paid its shareholders a dividend for the last three years.

Thames Water is also investing £4bn in a 'super sewer' to reduce discharged which is due to be completed in 2024.

Andree Frieze, Green Party Richmond Councillor and London Assembly candidate for South West London, has supported a campaign by London Waterkeepers to make sure Thames Water informs residents when they discharge sewage into the Thames from a range of sewage works in the area.

These include the Hogsmill Sewage Works and Kingston Main Sewage Pumping Station.

Cllr Frieze said: "Regulators rely on self-reporting by water companies and there is no way for river users to know when these controlled sewage overflows happen.

"This is why I support London Waterkeepers in their campaign demanding that Thames Water provides accurate, real-time and publicly available information on when overflows happen.

"Furthermore, Green Party policy calls for the banning of all discharges to water of any toxic substances."