Seversky Donets River - Geography and Hydrology

Geography and Hydrology

The Seversky Donets is the largest river of eastern Ukraine and the largest tributary of the Don. Its total length is 1,053 km (654 mi) and the basin area is 98,900 km2 (38,200 sq mi). The average annual flow is 25 m3 (880 cu ft) near the source and 200 m3 (7,100 cu ft) at the confluence to the Don.

The Seversky Donets originates on the Central Russian Upland, near Podolhi village, Prokhorovka area, north of Belgorod, at an elevation of 200 m (660 ft) above sea level. Its basin contains over 3000 rivers, of which 425 are longer than 10 km (6.2 mi) and 11 are longer than 100 km (62 mi); 1011 of those rivers directly flow into Seversky Donets. These rivers are mostly fed by melting snow, and thus the water supply is uneven during the year. The spring flood takes about 2 months from February to April, during this period the water level rises by 3–8 m (9.8–26 ft). Excessive flooding is rare due to abundant artificial water reservoirs constructed along the river.

The river width mostly ranges between 30 and 70 m (98 and 230 ft), sometimes reaching 100–200 m (330–660 ft) and even 4 km (2.5 mi) in the reservoir area. The river bottom is sandy and uneven, with the depth varying between 0.3 and 10 m (0 ft 10 in and 32 ft 10 in) and the average value of 2.5 m (8 ft 2 in). The river freezes between around mid-December and late March and is covered by 20–50 cm (7.9–20 in) thick ice. It flows into the Don at 218 km (135 mi) from its mouth, at an elevation of 5.5 m (18 ft) above sea level; thus the fall of the river is 195 m (640 ft) with the average gradient of 0.18 m/km.