Piz River
 Piz River (Russian: Пизь) is a right tributary of Buy River. It is 151 km in length with drainage basin 2210 km². It starts in Elovsky District of Perm Krai then flows through Chaikovsky District on the border with Bashkortostan. Flows into Buy River on the Border between Udmurt Republic and Bashkortostan in 20 km from its mouth. Main tributaries:Left: Bolshaya UsaRight: Posha