Integral Assessment of Water Quality in the Volga River Basin According to Monitoring Data in the 21st Century

The Volga River has been the main Russian river for several centuries. The river, originating on the Valdai Hills, crosses several natural and climatic zones on its way to the Caspian Sea: from the southern taiga to the dry steppes of the Caspian Lowland. According to the latest data, 45% of industrial enterprises and 50% of agricultural production in Russia are concentrated in the river basin. The anthropogenic load on the river with its tributaries and their basins significantly exceeds the load on other large Russian rivers. The largest contaminated wastewater volumes fall on the share of Moscow, Samara, Nizhny Novgorod, Yaroslavl, Saratov, Ufa, Volgograd, Balakhna, Tolyatti, Ulyanovsk, Cherepovets, Naberezhnye Chelny and other large cities. All these negative processes occur against the background of ongoing climate change. The article analyzes the Roshydromet hydrochemical monitoring data of river waters in the Volga River basin for the 2000–2021 period by water bodies and federal subjects. Regardless of the year water content, almost 70% of hydrochemical monitoring stations in the Volga River basin correspond to the third quality class (“polluted”). An integral assessment of the water quality in the Volga River basin shows that the situation has not changed significantly since the end of the last century. To improve the ecological condition of the Volga River basin, it is necessary to implement a set of measures for the protection and reproduction of water resources in catchment areas, rationalize water use systems, and reduce the volume of freshwater intake. Reducing water consumption is a necessary condition for reducing the wastewater volume discharged and, consequently, the number of pollutants contained in it. One of the problems is that almost all types of water use harm the surface waters’ natural quality, including the Volga River basin.