Key points are not available for this paper at this time.
The waters in some of the community water‐supply systems in the US often contain a myriad of microorganisms that carry past the disinfection barrier. Although the majority of those that survive and flourish are not pathogenic, the situation presents a potential danger. Here is an article on the sort of organisms that contribute to the trouble, with a description of factors relating to propagation of the species.
Geldreich et al. (Fri,) studied this question.