In the past decade there has been a rapid increase in waterborne outbreaks of disease associated with viral and protozoan agents, normally in drinking waters that were found to be microbially safe using the Coliform Index. For nearly a quarter of a century indicator organisms, in particular the coliform group, have been used to ensure the microbial quality of drinking water. Currently, world wide legislation to protect consumers is based on these outdated and unreliable tests and while there is considerable concern among scientists over their use, the water industry and regulators continue to place near total reliance on the Coliform Index. This book provides: * the first full account of the nature and applications of the Coliform Index * coverage of new and proposed water quality legislation: * details of emerging pathogens in water: * an evaluation of the role of the "coliform count" in future water quality analysis. It will be an essential tool for water companies at all levels, microbiologists, environmental health inspectors, environmental scientists and water engineers in industry whether working in developed countries or developing countries. Postgraduate students specialising in microbiology, civil and environmental engineering, environmental sciences and environmental health will find it a useful reference work as will undergraduates in these disciplines.