We all depend on services few of us would want to provide. The jobs are often unpleasant, sometimes shameful - not the kind of jobs you'd want to talk about. This series looks at these 'secret services' - and the people who provide them, in the face of ignorance, suspicion or distaste.
This film features a team of Manchester City Council sewermen in combat against the crumbling walls of the city's 1,500-mile network - one of the oldest in the country. Our cities would be cesspits of contagious disease without sewage systems. Yet the men who keep the sewers flowing know that the public would prefer to forget them and their work.
BBC Bristol