This program is in two parts. My father phoned me to say I had just missed the first part, but part 2 is on
Radio 4 on Wednesday 31 October 2007 at 11:00.
http://www.bbc.co.uk/radio4/cleansingthethames/
"Tracey Logan reports on the regular spillages from London's sewage
system into the River Thames and the government's proposed solution."