Assessment of surface water quality in the Siversky Donets river within Kharkiv region in 2023

Abstract

Purpose. Provide an assessment of the quality of the massif of surface waters of the Siverskyi Donets River within the Kharkiv region in 2023 based on the determination of water quality indices. Methods. The methods of the modified water pollution index (WPI) and the combinatorial water pollution index (CWPI). Results. State of the river water at the observation point of the v. Pechenigy according to the method of the modified water pollution index WPIF is estimated as II class characterized as "clean", WPIH - I class, "very clean"; according to the method of the combinatorial index of water pollution CWPIF - class III a, "dirty", CWPIH - class I, "slightly polluted". State of the river water at the observation point of the v. Eschar according to the method of the modified water pollution index of WPIF is estimated as III class characterized as "moderately polluted", WPIH - II class, "clean"; according to the method of the combinatorial index of water pollution CWPIF - class III b, "dirty", CWPIH - class II, "polluted". State of the river water at the observation point of the v/ Zadonetskyi according to the method of the modified index of water pollution, WPIF is estimated as III class characterized as "moderately polluted", WPIH is II class, "clean"; according to the method of the combinatorial index of water pollution CWPIF - class III b, "dirty", CWPIH - class I, "slightly polluted". Conclusions. It was determined that there are changes in water quality along the watercourse of the Siverskyi Donets River within the Kharkiv Region in 2023. There is a deterioration of water quality after the confluence of the Uda River, by 1.69 times the magnitude of the index change, then the state of water quality improves by 1.25 times the magnitude index changes, probably due to self-cleaning processes and lower anthropogenic load. The quality of water according to WPI indicators varies from 0.25 to 1.47 (from "very clean" to "moderately polluted"). The quality of water according to the CWPI indicators varies from 1.0 to 3.83 (from "slightly polluted" to "dirty"). It was established that according to both assessment methods and both standards, the quality of water in the Pechenigy reservoir, p. Pechenegs the best, and the worst water quality in the Siverskyi Donets River below the mouth of the Uda River, village Eschar.