We have carried out field studies and have given hygienic evaluation using reagents of the new generation "Valeus" based of salts polyhexamethyleneguanidine as a flocculant with disinfecting properties on the Novograd-Volyns'kyi river waterworks. Exploitation of three isolated water purifi-cation schemes on a water pipe allowed us to estimate the effectiveness of the reagent in different variants of its use in the preparation of drinking water. Field studies confirmed the high flocculation and decontamination efficiency from previous experiments, that allows to provide consistently high quality of drinking water on the microbiological and sanitary-chemical indicators when used in conjunction with a coagulant.