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Encyclopædia Britannica: Northern Dvina River Russian Severnaya Dvina,
river formed by the junction of the Sukhona and Yug rivers at the city of Velikiy Ustyug, in Vologod oblast (province) of Russia. The Northern Dvina is one of the largest and most important waterways of the northern European portion of Russia. It flows 462 miles (744 km) in a generally northwesterly direction and enters the Dvina inlet of the White Sea below the city of Arkhangelsk. The river drains a basin that, with an area of 138,000 square miles (357,000 square km), is larger than the whole of Poland.
Until its confluence with the tributary Vychegda River, the Northern Dvina is also called the Little Northern Dvina, with the remainder of its course known as the Greater Northern Dvina. The Northern Dvina's important tributaries include the Sukhona, Vychegda, Vaga, and Pinega rivers, all of which are themselves large rivers. At its mouth, the river's delta has an area of 425 square miles (1,100 square km) and is laced with a multitude of channels and branches.
The landscape drained by the Northern Dvina is formed of low, undulating plains sloping gradually down to the White Sea. The river's basin is bounded on the east by the low Timansky Ridge (where the Vychegda and its tributaries have their source) and the Northern Uvaly Hills, which form the watershed with the Volga River basin to the south. The northern and central portions of the basin have a thick covering of coniferous forests, while mixed forests, with conifers predominant, are found to the south. In all, more than half the basin is forest-clad. Beyond the left (west) bank of the river there are many low-lying bogs and lakes—including the large Lake Kubena—which are often the source of tributary rivers. Only along the river's floodplain are there open meadows.
The Northern Dvina is primarily fed by melting snow, which brings a marked maximum flow of 700,000 cubic feet (19,800 cubic m) per second in the spring. In its upper course, the river begins to freeze in November and becomes ice-free again by the end of April; the lower course is frozen for a slightly longer period. The spring witnesses frequent ice jams and floods along the whole river.
The Northern Dvina is navigable for most of its length, and since early times it has been the chief waterborne-transport route of northern European Russia. Early fur hunters and colonists used the river, and monasteries and towns (including Arkhangelsk) were later established at important confluences. The river retains its economic importance and is linked with the Volga-Baltic Waterway via the Sukhona River. The Northern Dvina's main cargo is timber, which is cut on a large scale throughout the basin and rafted to sawmilling centres along the river's banks. The most important of these are Velikiy Ustyug, Kotlas, and, above all, Arkhangelsk, which is the largest sawmilling centre in Russia. Arkhangelsk is a major timber-exporting port and one of the western terminal ports of the North Sea route. At the western end of the river's delta is the port of Severodvinsk.
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