Аннотация:The authors have developed a method for comparative analysis of water. This method involves water quality indicators benchmarking. The developed method presented in the paper differs from the method of simple harmonization of the maximum possible set of information involved in the field of comparison. Such an approach gives the possibility for comprehension and purposeful application of world experience in the qualitative performance of water supply. A benchmarking algorithm has been developed for the “Vodokanal of St. Petersburg” enterprise and the efficiency of its use has been determined. As a result of the benchmarking implementation, all indicators of St. Petersburg water supply have been substantially improved.