Most himalayan rivers originating in himalayan peaks are perennial because they are fed by the melting snow throughout the year. The rivers that have water throughout the year are called perennial rivers. Give reasons why the himalayan region consists of perennial rivers. Inundation canals are being converted to perennial canals because: Perennial rivers and lakes are those which bear water throughout the year while seasonal rivers and lakes have water only during a particular period, ie rainy season. In india himalayan rivers like ganga and bhramaputra are perennial rivers. These are both rain fed and formed through melting of the glaciers. Hence, option a is correct. (i) they remain operational only during the rainy season. What are perennial and non-perennial rivers? (ii) they get supply of water only when the rivers are in flood. Was this answer helpful?