Uchur

a river in Khabarovsk Krai and the Yakut ASSR; a right tributary of the Aldan River, which flows through the Lena basin. The Uchur measures 812 km in length and drains an area of 113,000 sq km. It originates in the eastern extremity of the Stanovoi Range and flows through the eastern edge of the Aldan Plateau. It is fed mainly by rain. High water occurs from May to September. The mean flow rate is 1,345 cu m per sec; the maximum flow rate is 21,600 cu m per sec (154 km from the mouth), and the minimum flow rate is 40 cu m per sec. The river freezes over in its lower course in November, and the ice breaks up in May. There are polynyas all winter in areas where thermal waters are released. The main tributaries are the Uian, Tyrkan, Gonam, and Gynym, all of which are on the left.