HC Deb 13 May 1985 vol 79 c20W
Mr. Deakins

asked the Secretary of State for the Environment what information is available to him about the proportion of sewage leaking through faulty sewers; what are the risks from such leakage of pollution of water sources; and if he will make a statement.

Mr. Macfarlane

Flow volumes in sewers, which include rain water run-off, are not generally recorded and therefore no estimate of leakage from sewers can be made. As a rule, water sources are located well away from sewers as a precaution against contamination. Further protection is given by disinfection at water treatment works where water enters the public supply system, and by regular sampling and analysis. These precautions are generally effective and sewage contamination incidents are very rare.