The article deals with the current issues of interconnection between public health and the quality of water resources. It was proposed to determine environmental safety areas in the basins of small rivers based on environmental morbidity valuation. Four phases are herewith determined: hazard identification, exposure assessment, environmental mortality rate assessment, decision-making regarding the need for implementation and water protection measures. In order to assess the influence of the state of river quality on the health status of the population in the certain administrative region, the impact factor of recreational water use was introduced. The risks related to organoleptic, sanitary and toxicological properties of water; epidemiological water hazard are considered.