Agency:.Produced by the National Film Board of Canada for the Canadian Department of National Health and Welfare.

Director, Harold Randall ; editing, Harold Randall ; producer, Vincent Paquette ; script, Harold Randall, Vincent Paquette ; camera, Charles Beddoe.

Narrator, Vincent Paquette.

Recorded 1947.

An account of how a city's water supply is purified. Each stage of purification in a filtration plant is shown, together with the complex system of underground mains serving all parts of the city. The safeguarding of water supplies on common carriers (trains, ships, aircraft) through regular government laboratory analyses is illustrated. The film closes with a glimpse of developments in the treatment of water supplies, including the addition of fluorine.

Mode of access: World Wide Web.

Description based on online resource; title from title screen (National Film Board of Canada, viewed 2023-08-10).