Evaluation of the Environmental Safety of Water in a Small River for Economic Use

Changes in the hydrochemical regime of a small river due to anthropogenic load lead to a deterioration in water quality. Pollution of water bodies can affect the volume of production in the fisheries industry. Therefore, a pressing issue for modern fisheries is the continuous monitoring and comprehensive ecological assessment of the quality of surface waters. The study aims to investigate the water quality index (WQI) for fish farming in the Umanka River within the city limits of Uman. As a typical urban river, Umanka experiences the influence of slow water flow, constant discharge of polluted water, ecological degradation, and weak self-purification. Therefore, the need to study and improve the water quality of the Umanka River is quite evident. WQIs are calculated based on the results of analytical measurements of hydrochemical properties of water, such as dissolved oxygen, pH, total (bicarbonate) alkalinity, total mineralization, nitrates, nitrites, ammonium nitrogen, etc. Confirmation of a moderate increase in the concentration of ion composition indicators in the water section studied after the city of Uman is provided by the results of WQI calculations for fish farming during 2021 and 2022 for the analyzed water samples in the direction of the Umanka River flow. Judging by the QWI values for fisheries purposes in 2021, waters from sampling points 1–5 are characterized as “Satisfactory,” with the exceptions being points 6 as “Good” and 7 as “Very Poor.” In 2022, water from the study area in the city of Uman (points 1 and 2) is characterized as “Good,” while the others (points 3–7) are considered “Satisfactory.” Thus, there is an observed deterioration in water quality for fish farming in the research area after the city of Uman.