Selemdzha
View of the river near Ekimchan
Zeya basin
Native name	Селемджа (Russian)
Location
Country	Russia
Physical characteristics
Source	Bureya Range
• coordinates	52°26′18″N 134°36′30″E / 52.43833°N 134.60833°E / 52.43833; 134.60833
• elevation	1,550 m (5,090 ft)
Mouth	Zeya
• coordinates	51°43′58″N 128°51′53″E / 51.73278°N 128.86472°E / 51.73278; 128.86472
• elevation	155 m (509 ft)
Length	647 km (402 mi)
Basin size	68,600 km2 (26,500 sq mi)
Basin features
Progression	Zeya→ Amur→ Sea of Okhotsk

The Selemdzha (Russian: Селемджа) is a river in the Amur Region of Russia. It is the biggest, left tributary of the Zeya. The length of the river is 647 km. The area of its basin 68,600 km².^[1]

Course

The Selemdzha has its source where three mountain ranges meet the Bureya Range, the Dusse-Alin from the south, the Ezop Range from the west and the Yam-Alin from the north, and flows first northwest with the Selemdzha Range to the north, and then westwards across the Zeya-Bureya Plain.^[2] The Baikal–Amur Mainline crosses the river just west of Fevralsk and reaches the Zeya north of the Trans-Siberian Railway and Blagoveshchensk.

Its main tributaries are the Ulma and Byssa on the left, as well as the Nora and Orlovka (Mamyn) on the right. The Selemdzha freezes up in early November and stays under the ice until early May.^[2]