The used methodology of the scientific substantiation of indicators is in the establishment of the conformity of laws of vital activity of indicator and pathogenic microorganisms in the real conditions of the action of the complex of factors, including disinfecting agents. In the one water sample simultaneously there were determined both the general indicator (GICB), thermotolerant (TTCB), glucose positive (GPCB) coliform bacteria, E.coli. On the base of long-term research in the various regions of the Russian Federation, as well with bearing in mind the analysis of domestic and foreign data, comparing the water quality and the incidence of intestinal infections in population it is recommended to use the index of determination of the total number glucose positive coliform bacteria (GPCB), which brings together a much broader range of bacteria of the Enterobacteriaceae family in comparison with total coliform bacteria (TCB) and thermotolerant coliform bacteria (TTCB) and warrants the absence in the test volume of water as an indicator lactose positive (E.coli, TCB, TTCB) and pathogens (salmonella) and potentially pathogenic bacteria which do not ferment lactose. Proposed index of GPCB is shown to allow to assess epidemiological risks not only more accurate, but also more efficiently without increasing the cost performance of bacteriological research.
