Assessment of surface water quality of the Seversky Donets river within Kharkiv region in 2024

Purpose. To provide an assessment of the quality of surface waters of the Siverskyi Donets River within the Kharkiv region in 2024 according to state monitoring data based on the determination of water quality indices. Methods. Analytical, modified water pollution index (MPI), combinatorial water pollution index (CPI). Results. An analysis of monitoring data of the Siverskyi Donets River within the Kharkiv region in 2024 was carried out for the posts of the village of Pechenyhi, the village of Eskhar, the village of Zadonetske according to six main indicators. It was determined that the water quality in the Pechenyhi Reservoir belongs to the II quality class according to two methods, but according to the modified MPI method it is characterized as “clean”, and according to the CPI method – as “polluted”. Water quality below the mouth of the Uda River, the village of According to the modified IZV method, Eschar belongs to the III quality class and is characterized as “moderately polluted”, and according to the KIZ method, the water belongs to the IV quality class and is characterized as “very dirty”. The water quality at the post of the village of Zadonetske belongs to the III quality class according to two methods, but according to the modified IZV method, it is characterized as “moderately polluted”, and according to the KIZ method, it is characterized as “dirty”. In 2024, compared to 2023, the water quality in the Pechenizhsky reservoir improved, and at the post of the village of Eschar it deteriorated. At the post of the village of Zadonetske, according to the IZV method, a deterioration in water quality is noted, and according to the KIZ method, on the contrary, an improvement. The hydrochemical indicators that determine water quality are BOD5, nitrogen compounds and sulfates. Conclusions. Along the watercourse of the Siverskyi Donets River within the Kharkiv region in 2024, changes in water quality occur. Deterioration of water quality is observed after the confluence of the Uda River, which is subjected to significant anthropogenic pressure. Water quality in the Siverskyi Donets varies from “clean” to “moderately polluted” according to the modified IZV method, and from “polluted” to “very dirty” according to the KIZ method.