Северский Донец: История и значение реки в Украине и России.

River in Ukraine and Russia

The Seversky Donets (Lang ru) or Siverskyi Donets (Сіверський Донець), usually simply called the Donets, is a river on the south of the East European Plain. It originates in the Central Russian Upland, north of Belgorod, flows south east through Ukraine (Kharkiv, Donetsk and Luhansk Oblasts) and then again through Russia (Rostov Oblast) to join the river Don, about from the Sea of Azov. The Donets is the fourth longest river in Ukraine, and the largest in eastern Ukraine, where it is an important source of fresh water. It gives its name to the Donets Basin, known commonly as the Donbas, an important coal mining and industrial region in Ukraine.

The names Don and its diminutive Donets are derived from Iranic, Sarmatian Dānu "the river". Scytho Sarmatians inhabited the areas to the north of the Black Sea from 1100 BC into the early medieval times. In the 2nd century CE Ptolemy knew the river Don, into which the Donets flows, as Tanais, and Western Europeans recognized that the Don had a significant tributary which they called either the small Tanais or Donetz. The Slavic name of Seversky Donets derived from the fact that the river originates from the land of Severians. As the Italian Polish chronicler Alexander Guagnini (1538–1614) wrote: "There is also another, small Tanais, which originates in the Seversky Principality (for this reason it is called Donets Seversky) and flows into the large Tanais above Azov".

The river played a crucial role for its ancient settlers as a source of water and food, means of transportation and trade route. The first archaeological evidence of settlers relates to Cheulean and Acheulean periods of Lower Paleolithic through stone tools (axes) found on the river banks near Izium city of Kharkiv Oblast and in Luhansk Oblast. Over the ages, the river banks were populated by tribals of various cultures, including Mousterian, Yamna, Catacomb, Scythian, Alan, Khazar and later Slavic cultures. Many of the related tribals had nomadic lifestyle characteristic of Kipchak people, Golden Horde and later of Cossacks. The river flows through the historic lands of Sloboda Ukraine as well as the lands of Don River Host. The many Cossacks became later assimilated into the strengthening Russian Empire, which had rebuilt and reinforced the fortress of Belgorod and cities of Kyiv, Izium, Luhansk, Chuhuiv and others in order keep defensive lines against the raids of nomads from the south east. Later, the protective role of the river basin gave way to economic needs. In the 18th–19th centuries, the river was extensively used for watermills, which numbered by hundreds by the end of the 18th century, and the mill dams interrupted navigation on the river.

Industrialization in the 20th century shifted interests to mineral exploitation in Donbas, with water hungry plants concentrated mostly in Kyiv, Luhansk and Donetsk. Already by the 1930s, Kharkiv, Donetsk and Luhansk were lacking water forcing the authorities to gradually create a network of canals and reservoirs. In 1936, the Kochetok Reservoir was created and coupled to the water system of Kharkiv. As a result of the industrial activity, the wild nature of Donets Basin transformed into an industrial settlement. After the breakup of the USSR, most of the basin territory became part of Ukraine.

During the War in Donbas, Luhansk Oblast was roughly split along the river between the Luhansk People's Republic, which controlled most of the portion of the oblast south of the Donets, and the Ukrainian government, which controlled most of the territory north of the Donets. In May 2022, Russian attempts to cross the Donets above Lysychansk were stopped in the operationally decisive Battle of the Siverskyi Donets.

Being one of the largest rivers in Ukraine, the Donets is very intensively used in farming and industry. Ukraine alone uses more than of river waters per year, half of which is returned as polluted discharges; this consumption effectively reduces river runoff by The industrial development of the 19th century reduced the groundwater levels of the basin. This resulted in shallowing of the river and slowed navigation. Until the mid 19th century, the river was rich in fish which population rapidly declined since then. In Kharkiv Oblast, water is contaminated by industrial and communal wastes of Belgorod, Izium and Shebekino cities, but the water is partially purified through the Pechenizke Reservoir. The density of plants and thus the contamination increase downstream in Donetsk and Luhansk areas, especially around Lysychansk and Sievierodonetsk, about 400 km from the mouth. Some tributaries of the Donets, such as Kozenyi Butt, Bakhmut and Lugan are so polluted that consuming fish caught there is dangerous.

The Donets hosts 44 species of fish, predominantly small fishes such as European perch, rutilus and common rudd. Medium and large species include bream, perch, catfish and pike and are becoming increasingly rare. Near Pechenizke Reservoir a large hatchery of carp has successfully operated since 1967.

On the banks of the river, in the floodplain wetlands, there are abundant water frogs, toads (especially green toad), smooth and great crested newts and less common grass snake, dice snake and European pond terrapin. The most picturesque part is probably near the town of Izium, which hosts a National Park of Holy Mountains. Down to Lysychansk, the water is clean for swimming, and there are many sandy beaches on the shores. Near Pechenizke Reservoir, there are several health resorts.