On this week's episode of ClimateCast, Tom Heap gets exclusive access to London's super sewer, the solution to the Thames's poo problem.

London's iconic river is one of thousands up and down the country subject to raw sewage flowing into the water whenever there's rain, causing problems for the natural environment as well as the people who enjoy it.

Tom visits the riverside to assess just how big the problem at hand is. He's also joined by Alastair Chisholm from the Chartered Institute of Water Environmental Management, to ask who is going to pay to clean up UK waters.

Producer: Emma Rae Woodhouse
Editor: Paul Stanworth