(also Up), a river in Transcarpathian Oblast, Ukrainian SSR, with its lower course in Czechoslovakia, where it is part of the Bodrog River (a tributary of the Tisza) system. The Uzh is 133 km long and drains an area of 2,750 sq km. It is fed mainly by rain. The mean flow rate 33 km from the mouth is 28.6 cu m per sec. The Onokov and Uzhgorod hydroelectric power plants are on the river. The city of Uzhgorod is in the Uzh River valley.

(also Usha), a river in Zhitomir and Kiev oblasts, Ukrainian SSR; a right tributary of the Pripiat’ River of the Dnieper River basin. The Uzh is 256 km long and drains an area of 8,080 sq km. It flows through Poles’e and empties into Pripiat’ Bay of the Kiev Reservoir. The river is fed mainly by snow. The mean flow rate 16 km from the mouth is 24.7 cu m per sec. The river freezes between November and early February and opens up between March and mid-April. The city of Korosten’ is situated on the Uzh.